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Rajan R, Makrai E, Lee JH, Singh S, Chinnery HR, Downie LE. Evaluating the efficacy and safety of therapeutic interventions for corneal neuropathy: A systematic review. Ocul Surf 2024; 33:80-98. [PMID: 38688453 DOI: 10.1016/j.jtos.2024.04.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 04/19/2024] [Accepted: 04/24/2024] [Indexed: 05/02/2024]
Abstract
Corneal neuropathy involves corneal nerve damage that disrupts ocular surface integrity, negatively impacting quality-of-life from pain and impaired vision. Any ocular or systemic condition that damages the trigeminal nerve can lead to corneal neuropathy. However, the condition currently does not have standardized diagnostic criteria or treatment protocols. The primary aim of this systematic review was to evaluate the efficacy and safety of interventions for treating corneal neuropathy. Randomized controlled trials (RCTs) that investigated corneal neuropathy treatments were eligible if the intervention(s) was compared to a placebo or active comparator. Comprehensive searches were conducted in Ovid MEDLINE, Ovid Embase and clinical trial registries from inception to July 2022. The Cochrane Risk-of-Bias 2 tool was used to assess study methodological quality. Certainty of the body of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Overall, 20 RCTs were included. Evaluated interventions comprised regenerative therapies (n = 6 studies), dietary supplements (n = 4), anti-glycemic agents (n = 3), combination therapy (n = 3), supportive therapies (n = 2) and systemic pain pharmacotherapies (n = 2). Nine RCTs were judged at high risk of bias for most outcomes. Definitions for corneal neuropathy in the populations varied substantially across studies, consistent with lack of consensus on diagnostic criteria. A diverse range of outcomes were quantified, likely reflecting absence of an agreed core outcome set. There was insufficient evidence to draw definitive conclusions on the efficacy or safety of any intervention. There was low or very low certainty evidence for several neuroregenerative agents and dietary supplements for improving corneal nerve fiber length in corneal neuropathy due to dry eye disease and diabetes. Low or very low certainty evidence was found for neuroregenerative therapies and dietary supplements not altering corneal immune cell density. This review identifies a need to standardize the clinical definition of corneal neuropathy and define a minimum set of core outcome measures. Together, this will provide a foundation for improved phenotyping of clinical populations in studies, and improve the capacity to synthesize data to inform evidence-based care. Protocol registration: PROSPERO ID: CRD42022348475.
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Affiliation(s)
- Rajni Rajan
- Department of Optometry and Vision Sciences, University of Melbourne, Carlton, Victoria, Australia
| | - Eve Makrai
- Department of Optometry and Vision Sciences, University of Melbourne, Carlton, Victoria, Australia
| | - Ji-Hyun Lee
- Department of Optometry and Vision Sciences, University of Melbourne, Carlton, Victoria, Australia
| | - Sumeer Singh
- Department of Optometry and Vision Sciences, University of Melbourne, Carlton, Victoria, Australia
| | - Holly R Chinnery
- Department of Optometry and Vision Sciences, University of Melbourne, Carlton, Victoria, Australia
| | - Laura E Downie
- Department of Optometry and Vision Sciences, University of Melbourne, Carlton, Victoria, Australia.
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2
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Gad H, Mohammed I, Dauleh H, Pasha M, Al-Barazenji T, Hussain K, Malik RA. Case report: Nerve fiber regeneration in children with melanocortin 4 receptor gene mutation related obesity treated with semaglutide. Front Endocrinol (Lausanne) 2024; 15:1385463. [PMID: 38974580 PMCID: PMC11227249 DOI: 10.3389/fendo.2024.1385463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Accepted: 06/07/2024] [Indexed: 07/09/2024] Open
Abstract
Melanocortin 4 receptor (MC4R) mutations are the commonest cause of monogenic obesity through dysregulation of neuronal pathways in the hypothalamus and prefrontal cortex that regulate hunger and satiety. MC4R also regulates neuropathic pain pathways via JNK signaling after nerve injury. We show evidence of corneal small fiber degeneration in 2 siblings carrying a heterozygous missense variant c.508A>G, p.Ille170Val in the MC4R gene. Both children were treated with once weekly semaglutide for 6 months with no change in weight, and only a minor improvement in HbA1c and lipid profile. However, there was evidence of nerve regeneration with an increase in corneal nerve fiber density (CNFD) [child A (13.9%), child B (14.7%)], corneal nerve branch density (CNBD) [child A (110.2%), child B (58.7%)] and corneal nerve fiber length (CNFL) [child A (21.5%), child B (44.0%)].
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Affiliation(s)
- Hoda Gad
- Research Department, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Idris Mohammed
- Endocrinology Department, Sidra Medicine, Doha, Qatar
- College of Health & Life Sciences, Hamad Bin Khalifa University, Doha, Qatar
| | - Hajar Dauleh
- Endocrinology Department, Sidra Medicine, Doha, Qatar
| | - Maheen Pasha
- Endocrinology Department, Sidra Medicine, Doha, Qatar
| | | | | | - Rayaz A. Malik
- Research Department, Weill Cornell Medicine-Qatar, Doha, Qatar
- Institute of Cardiovascular Medicine, University of Manchester, Manchester, United Kingdom
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3
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Gad H, Elgassim E, Lebbe A, MacDonald RS, Baraka A, Petropoulos IN, Ponirakis G, Ibrahim NO, Malik RA. Corneal confocal microscopy detects early nerve regeneration after pharmacological and surgical interventions: Systematic review and meta-analysis. J Peripher Nerv Syst 2024; 29:173-184. [PMID: 38887985 DOI: 10.1111/jns.12641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2024] [Revised: 05/30/2024] [Accepted: 06/03/2024] [Indexed: 06/20/2024]
Abstract
Corneal confocal microscopy (CCM) is an ophthalmic imaging technique that enables the identification of corneal nerve fibre degeneration and regeneration. To undertake a systematic review and meta-analysis of studies utilizing CCM to assess for corneal nerve regeneration after pharmacological and surgical interventions in patients with peripheral neuropathy. Databases (EMBASE [Ovid], PubMed, CENTRAL and Web of Science) were searched to summarize the evidence from randomized and non-randomized studies using CCM to detect corneal nerve regeneration after pharmacological and surgical interventions. Data synthesis was undertaken using RevMan web. Eighteen studies including 958 patients were included. CCM identified an early (1-8 months) and longer term (1-5 years) increase in corneal nerve measures in patients with peripheral neuropathy after pharmacological and surgical interventions. This meta-analysis confirms the utility of CCM to identify nerve regeneration following pharmacological and surgical interventions. It could be utilized to show a benefit in clinical trials of disease modifying therapies for peripheral neuropathy.
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Affiliation(s)
- Hoda Gad
- Research Department, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Einas Elgassim
- Research Department, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Ahamed Lebbe
- Research Department, Weill Cornell Medicine-Qatar, Doha, Qatar
| | | | - Areej Baraka
- Research Department, Weill Cornell Medicine-Qatar, Doha, Qatar
| | | | | | - Nada O Ibrahim
- Research Department, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Rayaz A Malik
- Research Department, Weill Cornell Medicine-Qatar, Doha, Qatar
- Institute of Cardiovascular Medicine, University of Manchester, Manchester, UK
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Rebelos E, Anastasiou IA, Tentolouris A, Papanas N, Jude E. What is New on Diabetic Neuropathy? Insights from the 2023 ADA and EASD Conferences. INT J LOW EXTR WOUND 2024:15347346241233938. [PMID: 38414376 DOI: 10.1177/15347346241233938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/29/2024]
Abstract
Diabetic neuropathy is a common complication of diabetes; yet its pathophysiology is still incompletely understood and until today, there is no specific treatment against it. In the two 2023 large congresses on diabetes (American Diabetes Association, ADA, European Association for the Study of Diabetes, EASD), several high-level studies have been presented. They have attempted to delineate the pathophysiology of DN, the characteristics of affected patients, and future potential treatments. We herein review the presented studies on diabetic neuropathy at these diabetes congresses and discuss the needs for future research on this topic.
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Affiliation(s)
- Eleni Rebelos
- Diabetes Center, First Department of Propaedeutic Internal Medicine, Medical School, National and Kapodistrian University of Athens, Laiko General Hospital, Athens, Greece
- Turku PET Centre, University of Turku, Turku, Finland
| | - Ioanna A Anastasiou
- Diabetes Center, First Department of Propaedeutic Internal Medicine, Medical School, National and Kapodistrian University of Athens, Laiko General Hospital, Athens, Greece
- Department of Pharmacology, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Anastasios Tentolouris
- Diabetes Center, First Department of Propaedeutic Internal Medicine, Medical School, National and Kapodistrian University of Athens, Laiko General Hospital, Athens, Greece
| | - Nikolaos Papanas
- Diabetes Centre-Diabetic Foot Clinic, Second Department of Internal Medicine, Democritus University of Thrace, Alexandroupolis, Greece
| | - Edward Jude
- Department of Medicine, Tameside and Glossop Integrated Care NHS Foundation Trust, Ashton-under-Lyne, UK
- University of Manchester, Manchester, UK
- Manchester Metropolitan University, Manchester, UK
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Liu C, Wu T, Ren N. Glucagon-like peptide-1 receptor agonists for the management of diabetic peripheral neuropathy. Front Endocrinol (Lausanne) 2024; 14:1268619. [PMID: 38313844 PMCID: PMC10836428 DOI: 10.3389/fendo.2023.1268619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 12/27/2023] [Indexed: 02/06/2024] Open
Abstract
Diabetes mellitus is a prevalent chronic disease characterized by hyperglycemia. Diabetic peripheral neuropathy (DPN) is one of the complications of diabetes mellitus and is caused by neuron injury induced by hyperglycemic circumstances. The incidence of DPN varies among different countries and regions, ranging from nearly 20% to over 70%. Patients with DPN may encounter symmetric pain or discomfort of the extremes, leading to reduced quality of life and even amputation. The pharmacological management for painful DPN mainly includes antidepressants due to their analgesic effects. Nevertheless, effective therapies to impact the pathogenesis and progression of DPN are lacking. Glucagon-like peptide-1 receptor (GLP-1R) agonists show efficacy in controlling blood glucose and serve as a treatment modality for diabetes mellitus. In recent years, evidence has been proposed that GLP-1R agonists exert neuroprotective effects through modulating inflammation, oxidative stress, and mitochondrial dysfunction. On the other hand, clinical evidence on the potential of GLP-1R agonists for treating DPN is still controversial and limited. This narrative review summarizes the preclinical and clinical studies investigating the capacity of GLP-1R agonists as therapeutic agents for DPN.
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Affiliation(s)
- Chunyan Liu
- Department of Endocrinology, First Affiliated Hospital, Heilongjiang University of Chinese Medicine, Harbin, China
| | - Tianqiang Wu
- Department of Integrated Traditional Chinese and Western Medicine, Heilongjiang University of Chinese Medicine, Harbin, China
| | - Na Ren
- Department of Endocrinology, First Affiliated Hospital, Heilongjiang University of Chinese Medicine, Harbin, China
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Goldney J, Sargeant JA, Davies MJ. Incretins and microvascular complications of diabetes: neuropathy, nephropathy, retinopathy and microangiopathy. Diabetologia 2023; 66:1832-1845. [PMID: 37597048 PMCID: PMC10474214 DOI: 10.1007/s00125-023-05988-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 07/17/2023] [Indexed: 08/21/2023]
Abstract
Glucagon-like peptide-1 receptor agonists (GLP-1RAs, incretin mimetics) and dipeptidyl peptidase-4 inhibitors (DPP-4is, incretin enhancers) are glucose-lowering therapies with proven cardiovascular safety, but their effect on microvascular disease is not fully understood. Both therapies increase GLP-1 receptor agonism, which is associated with attenuation of numerous pathological processes that may lead to microvascular benefits, including decreased reactive oxygen species (ROS) production, decreased inflammation and improved vascular function. DPP-4is also increase stromal cell-derived factor-1 (SDF-1), which is associated with neovascularisation and tissue repair. Rodent studies demonstrate several benefits of these agents in the prevention or reversal of nephropathy, retinopathy and neuropathy, but evidence from human populations is less clear. For nephropathy risk in human clinical trials, meta-analyses demonstrate that GLP-1RAs reduce the risk of a composite renal outcome (doubling of serum creatinine, eGFR reduction of 30%, end-stage renal disease or renal death), whereas the benefits of DPP-4is appear to be limited to reductions in the risk of albuminuria. The relationship between GLP-1RAs and retinopathy is less clear. Many large trials and meta-analyses show no effect, but an observed increase in the risk of retinopathy complications with semaglutide therapy (a GLP-1RA) in the SUSTAIN-6 trial warrants caution, particularly in individuals with baseline retinopathy. Similarly, DPP-4is are associated with increased retinopathy risk in both trials and meta-analysis. The association between GLP-1RAs and peripheral neuropathy is unclear due to little trial evidence. For DPP-4is, one trial and several observational studies show a reduced risk of peripheral neuropathy, with others reporting no effect. Evidence in other less-established microvascular outcomes, such as microvascular angina, cerebral small vessel disease, skeletal muscle microvascular disease and autonomic neuropathies (e.g. cardiac autonomic neuropathy, gastroparesis, erectile dysfunction), is sparse. In conclusion, GLP-1RAs are protective against nephropathy, whereas DPP-4is are protective against albuminuria and potentially peripheral neuropathy. Caution is advised with DPP-4is and semaglutide, particularly for patients with background retinopathy, due to increased risk of retinopathy. Well-designed trials powered for microvascular outcomes are needed to clarify associations of incretin therapies and microvascular diseases.
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Affiliation(s)
- Jonathan Goldney
- Diabetes Research Centre, College of Life Sciences, University of Leicester, Leicester, UK.
- NIHR Leicester Biomedical Research Centre, University Hospitals of Leicester NHS Trust and University of Leicester, Leicester, UK.
| | - Jack A Sargeant
- NIHR Leicester Biomedical Research Centre, University Hospitals of Leicester NHS Trust and University of Leicester, Leicester, UK
- Leicester Diabetes Centre, University Hospitals of Leicester NHS Trust, Leicester, UK
| | - Melanie J Davies
- Diabetes Research Centre, College of Life Sciences, University of Leicester, Leicester, UK
- NIHR Leicester Biomedical Research Centre, University Hospitals of Leicester NHS Trust and University of Leicester, Leicester, UK
- Leicester Diabetes Centre, University Hospitals of Leicester NHS Trust, Leicester, UK
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García-Casares N, González-González G, de la Cruz-Cosme C, Garzón-Maldonado FJ, de Rojas-Leal C, Ariza MJ, Narváez M, Barbancho MÁ, García-Arnés JA, Tinahones FJ. Effects of GLP-1 receptor agonists on neurological complications of diabetes. Rev Endocr Metab Disord 2023; 24:655-672. [PMID: 37231200 PMCID: PMC10404567 DOI: 10.1007/s11154-023-09807-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/21/2023] [Indexed: 05/27/2023]
Abstract
Emerging evidence suggests that treatment with glucagon-like peptide-1 receptor agonists (GLP-1 RAs) could be an interesting treatment strategy to reduce neurological complications such as stroke, cognitive impairment, and peripheral neuropathy. We performed a systematic review to examine the evidence concerning the effects of GLP-1 RAs on neurological complications of diabetes. The databases used were Pubmed, Scopus and Cochrane. We selected clinical trials which analysed the effect of GLP-1 RAs on stroke, cognitive impairment, and peripheral neuropathy. We found a total of 19 studies: 8 studies include stroke or major cardiovascular events, 7 involve cognitive impairment and 4 include peripheral neuropathy. Semaglutide subcutaneous and dulaglutide reduced stroke cases. Liraglutide, albiglutide, oral semaglutide and efpeglenatide, were not shown to reduce the number of strokes but did reduce major cardiovascular events. Exenatide, dulaglutide and liraglutide improved general cognition but no significant effect on diabetic peripheral neuropathy has been reported with GLP-1 RAs. GLP-1 RAs are promising drugs that seem to be useful in the reduction of some neurological complications of diabetes. However, more studies are needed.
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Affiliation(s)
- Natalia García-Casares
- Facultad de Medicina, Departamento de Medicina, Universidad de Málaga, Málaga, Spain.
- Instituto de Investigación Biomédica de Málaga (I.B.I.M.A), Málaga, Spain.
- Centro de Investigaciones Médico-Sanitarias (C.I.M.ES), Málaga, Spain.
- Departamento de Medicina, Facultad de Medicina, Universidad de Málaga, Centro de Investigaciones Médico Sanitarias (C.I.M.E.S), Universidad de Málaga, Instituto de Investigación Biomédica de Málaga (IBIMA), Campus Universitario de Teatinos s/n., Málaga, 29010, España.
| | | | - Carlos de la Cruz-Cosme
- Instituto de Investigación Biomédica de Málaga (I.B.I.M.A), Málaga, Spain
- Hospital Universitario Virgen de la Victoria de Málaga, Málaga, Spain
| | - Francisco J Garzón-Maldonado
- Instituto de Investigación Biomédica de Málaga (I.B.I.M.A), Málaga, Spain
- Hospital Universitario Virgen de la Victoria de Málaga, Málaga, Spain
| | - Carmen de Rojas-Leal
- Facultad de Medicina, Departamento de Medicina, Universidad de Málaga, Málaga, Spain
| | - María J Ariza
- Facultad de Medicina, Departamento de Medicina, Universidad de Málaga, Málaga, Spain
- Instituto de Investigación Biomédica de Málaga (I.B.I.M.A), Málaga, Spain
- Centro de Investigaciones Médico-Sanitarias (C.I.M.ES), Málaga, Spain
| | - Manuel Narváez
- Facultad de Medicina, Departamento de Medicina, Universidad de Málaga, Málaga, Spain
- Instituto de Investigación Biomédica de Málaga (I.B.I.M.A), Málaga, Spain
| | - Miguel Ángel Barbancho
- Facultad de Medicina, Departamento de Medicina, Universidad de Málaga, Málaga, Spain
- Instituto de Investigación Biomédica de Málaga (I.B.I.M.A), Málaga, Spain
- Centro de Investigaciones Médico-Sanitarias (C.I.M.ES), Málaga, Spain
| | | | - Francisco J Tinahones
- Facultad de Medicina, Departamento de Medicina, Universidad de Málaga, Málaga, Spain.
- Instituto de Investigación Biomédica de Málaga (I.B.I.M.A), Málaga, Spain.
- Hospital Universitario Virgen de la Victoria de Málaga, Málaga, Spain.
- Departamento de Medicina, Facultad de Medicina, Universidad de Málaga, Instituto de Investigación Biomédica de Málaga (IBIMA), Campus Universitario de Teatinos s/n., Málaga, 29010, España.
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Khan A, Kamal M, Alhothi A, Gad H, Adan MA, Ponirakis G, Petropoulos IN, Malik RA. Corneal confocal microscopy demonstrates sensory nerve loss in children with autism spectrum disorder. PLoS One 2023; 18:e0288399. [PMID: 37437060 DOI: 10.1371/journal.pone.0288399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2023] [Accepted: 06/24/2023] [Indexed: 07/14/2023] Open
Abstract
Autism spectrum disorder (ASD) is a developmental disorder characterized by difficulty in communication and interaction with others. Postmortem studies have shown cerebral neuronal loss and neuroimaging studies show neuronal loss in the amygdala, cerebellum and inter-hemispheric regions of the brain. Recent studies have shown altered tactile discrimination and allodynia on the face, mouth, hands and feet and intraepidermal nerve fiber loss in the legs of subjects with ASD. Fifteen children with ASD (age: 12.00 ± 3.55 years) and twenty age-matched healthy controls (age: 12.83 ± 1.91 years) underwent corneal confocal microscopy (CCM) and quantification of corneal nerve fiber morphology. Corneal nerve fibre density (fibers/mm2) (28.61 ± 5.74 vs. 40.42 ± 8.95, p = 0.000), corneal nerve fibre length (mm/mm2) (16.61 ± 3.26 vs. 21.44 ± 4.44, p = 0.001), corneal nerve branch density (branches/mm2) (43.68 ± 22.71 vs. 62.39 ± 21.58, p = 0.018) and corneal nerve fibre tortuosity (0.037 ± 0.023 vs. 0.074 ± 0.017, p = 0.000) were significantly lower and inferior whorl length (mm/mm2) (21.06 ± 6.12 vs. 23.43 ± 3.95, p = 0.255) was comparable in children with ASD compared to controls. CCM identifies central corneal nerve fiber loss in children with ASD. These findings, urge the need for larger longitudinal studies to determine the utility of CCM as an imaging biomarker for neuronal loss in different subtypes of ASD and in relation to disease progression.
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Affiliation(s)
- Adnan Khan
- Research Division, Weill Cornell Medicine-Qatar, Doha, Qatar
- Faculty of Health Sciences, Khyber Medical University, Peshawar, Pakistan
| | - Madeeha Kamal
- Department of Pediatrics, Sidra Medicine, Doha, Qatar
| | - Abdula Alhothi
- Department of Pediatrics, Hamad General Hospital, Doha, Qatar
| | - Hoda Gad
- Research Division, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Marian A Adan
- Department of Pediatrics, Hamad General Hospital, Doha, Qatar
| | | | | | - Rayaz A Malik
- Research Division, Weill Cornell Medicine-Qatar, Doha, Qatar
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Guldiken YC, Malik A, Petropoulos IN, Gad H, Elgassim E, Salivon I, Ponirakis G, Alam U, Malik RA. Where Art Thou O treatment for diabetic neuropathy: the sequel. Expert Rev Neurother 2023; 23:845-851. [PMID: 37602687 DOI: 10.1080/14737175.2023.2247163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 08/08/2023] [Indexed: 08/22/2023]
Abstract
INTRODUCTION Having lived through a pandemic and witnessed how regulatory approval processes can evolve rapidly; it is lamentable how we continue to rely on symptoms/signs and nerve conduction as primary endpoints for clinical trials in DPN. AREAS COVERED Small (Aδ and C) fibers are key to the genesis of pain, regulate skin blood flow, and play an integral role in the development of diabetic foot ulceration but continue to be ignored. This article challenges the rationale for the FDA insisting on symptoms/signs and nerve conduction as primary endpoints for clinical trials in DPN. EXPERT OPINION Quantitative sensory testing, intraepidermal nerve fiber density, and especially corneal confocal microscopy remain an after-thought, demoted at best to exploratory secondary endpoints in clinical trials of diabetic neuropathy. If pharma are to be given a fighting chance to secure approval for a new therapy for diabetic neuropathy, the FDA needs to reassess the evidence rather than rely on 'opinion' for the most suitable endpoint(s) in clinical trials of diabetic neuropathy.
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Affiliation(s)
- Yigit Can Guldiken
- Department of Neurology, Kocaeli University Research and Application Hospital, İzmit/Kocaeli, Turkey
| | - Ayesha Malik
- Barts and The London School of Medicine and Dentistry - Medicine, London, UK
| | | | - Hoda Gad
- Weill Cornell Medicine-Qatar, Qatar Foundation, Doha, Qatar
| | - Einas Elgassim
- Weill Cornell Medicine-Qatar, Qatar Foundation, Doha, Qatar
| | - Iuliia Salivon
- Weill Cornell Medicine-Qatar, Qatar Foundation, Doha, Qatar
| | | | - Uazman Alam
- Department of Cardiovascular and Metabolic Medicine, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, UK
| | - Rayaz A Malik
- Weill Cornell Medicine-Qatar, Qatar Foundation, Doha, Qatar
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Syed O, Jancic P, Knezevic NN. A Review of Recent Pharmacological Advances in the Management of Diabetes-Associated Peripheral Neuropathy. Pharmaceuticals (Basel) 2023; 16:801. [PMID: 37375749 DOI: 10.3390/ph16060801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 05/14/2023] [Accepted: 05/18/2023] [Indexed: 06/29/2023] Open
Abstract
Diabetic peripheral neuropathy is a common complication of longstanding diabetes mellitus. These neuropathies can present in various forms, and with the increasing prevalence of diabetes mellitus, a subsequent increase in peripheral neuropathy cases has been noted. Peripheral neuropathy has a significant societal and economic burden, with patients requiring concomitant medication and often experiencing a decline in their quality of life. There is currently a wide variety of pharmacological interventions, including serotonin norepinephrine reuptake inhibitors, gapentanoids, sodium channel blockers, and tricyclic antidepressants. These medications will be discussed, as well as their respective efficacies. Recent advances in the treatment of diabetes mellitus with incretin system-modulating drugs, specifically glucagon-like peptide-1 agonists, have been promising, and their potential implication in the treatment of peripheral diabetic neuropathy is discussed in this review.
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Affiliation(s)
- Osman Syed
- Advocate Illinois Masonic Medical Center, Department of Anesthesiology, Chicago, IL 60657, USA
- Chicago College of Osteopathic Medicine, Midwestern University, Downers Grove, IL 60515, USA
| | - Predrag Jancic
- Advocate Illinois Masonic Medical Center, Department of Anesthesiology, Chicago, IL 60657, USA
| | - Nebojsa Nick Knezevic
- Advocate Illinois Masonic Medical Center, Department of Anesthesiology, Chicago, IL 60657, USA
- Department of Anesthesiology, University of Illinois, Chicago, IL 60612, USA
- Department of Surgery, University of Illinois, Chicago, IL 60612, USA
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Kirthi V, Reed KI, Alattar K, Zuckerman BP, Bunce C, Nderitu P, Alam U, Clarke B, Hau S, Al-Shibani F, Petropoulos IN, Malik RA, Pissas T, Bergeles C, Vas P, Hopkins D, Jackson TL. Multimodal testing reveals subclinical neurovascular dysfunction in prediabetes, challenging the diagnostic threshold of diabetes. Diabet Med 2023; 40:e14952. [PMID: 36054221 PMCID: PMC10087038 DOI: 10.1111/dme.14952] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 08/18/2022] [Accepted: 08/22/2022] [Indexed: 11/28/2022]
Abstract
AIM To explore if novel non-invasive diagnostic technologies identify early small nerve fibre and retinal neurovascular pathology in prediabetes. METHODS Participants with normoglycaemia, prediabetes or type 2 diabetes underwent an exploratory cross-sectional analysis with optical coherence tomography angiography (OCT-A), handheld electroretinography (ERG), corneal confocal microscopy (CCM) and evaluation of electrochemical skin conductance (ESC). RESULTS Seventy-five participants with normoglycaemia (n = 20), prediabetes (n = 29) and type 2 diabetes (n = 26) were studied. Compared with normoglycaemia, mean peak ERG amplitudes of retinal responses at low (16-Td·s: 4.05 μV, 95% confidence interval [95% CI] 0.96-7.13) and high (32-Td·s: 5·20 μV, 95% CI 1.54-8.86) retinal illuminance were lower in prediabetes, as were OCT-A parafoveal vessel densities in superficial (0.051 pixels/mm2 , 95% CI 0.005-0.095) and deep (0.048 pixels/mm2 , 95% CI 0.003-0.093) retinal layers. There were no differences in CCM or ESC measurements between these two groups. Correlations between HbA1c and peak ERG amplitude at 32-Td·s (r = -0.256, p = 0.028), implicit time at 32-Td·s (r = 0.422, p < 0.001) and 16-Td·s (r = 0.327, p = 0.005), OCT parafoveal vessel density in the superficial (r = -0.238, p = 0.049) and deep (r = -0.3, p = 0.017) retinal layers, corneal nerve fibre length (CNFL) (r = -0.293, p = 0.017), and ESC-hands (r = -0.244, p = 0.035) were observed. HOMA-IR was a predictor of CNFD (β = -0.94, 95% CI -1.66 to -0.21, p = 0.012) and CNBD (β = -5.02, 95% CI -10.01 to -0.05, p = 0.048). CONCLUSIONS The glucose threshold for the diagnosis of diabetes is based on emergent retinopathy on fundus examination. We show that both abnormal retinal neurovascular structure (OCT-A) and function (ERG) may precede retinopathy in prediabetes, which require confirmation in larger, adequately powered studies.
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Affiliation(s)
- Varo Kirthi
- King's College London, London, UK
- King's College Hospital NHS Foundation Trust, London, UK
| | - Kate I Reed
- King's College Hospital NHS Foundation Trust, London, UK
| | | | | | - Catey Bunce
- Biomedical Research Centre, The Royal Marsden NHS Foundation Trust and the Institute of Cancer Research, London, UK
| | - Paul Nderitu
- King's College London, London, UK
- King's College Hospital NHS Foundation Trust, London, UK
| | - Uazman Alam
- University of Liverpool, Liverpool, UK
- Liverpool University Hospitals NHS Foundation Trust, Liverpool, UK
- Institute of Cardiovascular Sciences, Cardiac Centre, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK
| | - Bronagh Clarke
- Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Scott Hau
- Moorfields Eye Hospital NHS Foundation Trust, London, UK
- University College London, London, UK
| | | | | | - Rayaz A Malik
- Institute of Cardiovascular Sciences, Cardiac Centre, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK
- Division of Research, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Theodoros Pissas
- King's College London, London, UK
- University College London, London, UK
| | | | - Prashanth Vas
- King's College London, London, UK
- King's College Hospital NHS Foundation Trust, London, UK
| | - David Hopkins
- King's College London, London, UK
- King's College Hospital NHS Foundation Trust, London, UK
| | - Timothy L Jackson
- King's College London, London, UK
- King's College Hospital NHS Foundation Trust, London, UK
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12
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Petropoulos IN, Al-Shibani F, Bitirgen G, Ponirakis G, Khan A, Gad H, Mahfoud ZR, Altarawneh H, Rehman MH, John K, Al-Merekhi D, George P, Uca AU, Ozkagnici A, Ibrahim F, Francis R, Canibano B, Deleu D, El-Sotouhy A, Vattoth S, Own A, Shuaib A, Akhtar N, Kamran S, Malik RA. Corneal axonal loss as an imaging biomarker of neurodegeneration in multiple sclerosis: a longitudinal study. Ther Adv Neurol Disord 2023; 16:17562864221118731. [PMID: 36776530 PMCID: PMC9909084 DOI: 10.1177/17562864221118731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 07/23/2022] [Indexed: 02/09/2023] Open
Abstract
Background Resourceful endpoints of axonal loss are needed to predict the course of multiple sclerosis (MS). Corneal confocal microscopy (CCM) can detect axonal loss in patients with clinically isolated syndrome and established MS, which relates to neurological disability. Objective To assess corneal axonal loss over time in relation to retinal atrophy, and neurological and radiological abnormalities in MS. Methods Patients with relapsing-remitting (RRMS) (n = 68) or secondary progressive MS (SPMS) (n = 15) underwent CCM and optical coherence tomography. Corneal nerve fibre density (CNFD-fibres/mm2), corneal nerve branch density (CNBD-branches/mm2), corneal nerve fibre length (CNFL-mm/mm2) and retinal nerve fibre layer (RNFL-μm) thickness were quantified along with neurological and radiological assessments at baseline and after 2 years of follow-up. Age-matched, healthy controls (n = 20) were also assessed. Results In patients with RRMS compared with controls at baseline, CNFD (p = 0.004) and RNFL thickness (p < 0.001) were lower, and CNBD (p = 0.003) was higher. In patients with SPMS compared with controls, CNFD (p < 0.001), CNFL (p = 0.04) and RNFL thickness (p < 0.001) were lower. For identifying RRMS, CNBD had the highest area under the receiver operating characteristic (AUROC) curve (0.99); and for SPMS, CNFD had the highest AUROC (0.95). At follow-up, there was a further significant decrease in CNFD (p = 0.04), CNBD (p = 0.001), CNFL (p = 0.008) and RNFL (p = 0.002) in RRMS; in CNFD (p = 0.04) and CNBD (p = 0.002) in SPMS; and in CNBD (p = 0.01) in SPMS compared with RRMS. Follow-up corneal nerve loss was greater in patients with new enhancing lesions and optic neuritis history. Conclusion Progressive corneal and retinal axonal loss was identified in patients with MS, especially those with more active disease. CCM may serve as an imaging biomarker of axonal loss in MS.
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Affiliation(s)
| | - Fatima Al-Shibani
- Division of Research, Weill Cornell Medicine–Qatar of Cornell University, Doha, Qatar
| | - Gulfidan Bitirgen
- Department of Ophthalmology, Meram Faculty of Medicine, Necmettin Erbakan University, Konya, Turkey
| | - Georgios Ponirakis
- Division of Research, Weill Cornell Medicine–Qatar of Cornell University, Doha, Qatar
| | - Adnan Khan
- Division of Research, Weill Cornell Medicine–Qatar of Cornell University, Doha, Qatar
| | - Hoda Gad
- Division of Research, Weill Cornell Medicine–Qatar of Cornell University, Doha, Qatar
| | - Ziyad R. Mahfoud
- Division of Medical Education, Weill Cornell Medicine–Qatar of Cornell University, Doha, Qatar,Division of Epidemiology, Department of Population Health Sciences, Weill Cornell Medicine, New York, NY, USA
| | - Heba Altarawneh
- Division of Research, Weill Cornell Medicine–Qatar of Cornell University, Doha, Qatar
| | | | - Karen John
- Division of Research, Weill Cornell Medicine–Qatar of Cornell University, Doha, Qatar
| | - Dhabia Al-Merekhi
- Division of Research, Weill Cornell Medicine–Qatar of Cornell University, Doha, Qatar
| | - Pooja George
- Neuroscience Institute, Hamad Medical Corporation, Doha, Qatar
| | - Ali Ulvi Uca
- Department of Neurology, Meram Faculty of Medicine, Necmettin Erbakan University, Konya, Turkey
| | - Ahmet Ozkagnici
- Department of Neurology, Meram Faculty of Medicine, Necmettin Erbakan University, Konya, Turkey
| | - Faiza Ibrahim
- Neuroscience Institute, Hamad Medical Corporation, Doha, Qatar
| | - Reny Francis
- Neuroscience Institute, Hamad Medical Corporation, Doha, Qatar
| | | | - Dirk Deleu
- Neuroscience Institute, Hamad Medical Corporation, Doha, Qatar
| | | | - Surjith Vattoth
- Neuroscience Institute, Hamad Medical Corporation, Doha, Qatar
| | - Ahmed Own
- Neuroscience Institute, Hamad Medical Corporation, Doha, Qatar
| | - Ashfaq Shuaib
- Neuroscience Institute, Hamad Medical Corporation, Doha, Qatar
| | - Naveed Akhtar
- Neuroscience Institute, Hamad Medical Corporation, Doha, Qatar
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13
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Gad H, Elgassim E, Mohammed I, Alhaddad AY, Ahmed Hussein Zaky Aly H, Cabibihan JJ, Al-Ali A, Sadasivuni KK, Haji A, Lamine N, Khan A, Petropoulos IN, Ponirakis G, Kalteniece A, Ferdousi M, Azmi S, Alam U, Abuhelaiqa W, Jayyousi A, AlMohanadi D, Baagar K, Malik RA. Continuous glucose monitoring reveals a novel association between duration and severity of hypoglycemia, and small nerve fiber injury in patients with diabetes. Endocr Connect 2022; 11:e220352. [PMID: 36240043 PMCID: PMC9716363 DOI: 10.1530/ec-22-0352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 10/14/2022] [Indexed: 11/08/2022]
Abstract
Objective Continuous glucose monitoring (CGM) has revealed that glycemic variability and low time in range are associated with albuminuria and retinopathy. We have investigated the relationship between glucose metrics derived from CGM and a highly sensitive measure of neuropathy using corneal confocal microscopy in participants with type 1 and type 2 diabetes. Methods A total of 40 participants with diabetes and 28 healthy controls underwent quantification of corneal nerve fiber density (CNFD), corneal nerve branch density (CNBD), corneal nerve fiber length (CNFL) and inferior whorl length (IWL) and those with diabetes underwent CGM for four consecutive days. Results CNBD was significantly lower in patients with high glycemic variability (GV) compared to low GV (median (range) (25.0 (19.0-37.5) vs 38.6 (29.2-46.9); P = 0.007); in patients who spent >4% compared to <4% time in level 1 hypoglycemia (54-69 mg/dL) (25.0 (22.9-37.5) vs 37.5 (29.2-46.9); P = 0.045) and in patients who spent >1% compared to <1% time in level 2 hypoglycemia (<54 mg/dL) (25.0 (19.8-41.7) vs 35.4 (28.1-44.8); P = 0.04). Duration in level 1 hypoglycemia correlated with CNBD (r = -0.342, P = 0.031). Duration in level 1 (181-250 mg/dL) and level 2 (>250 mg/dL) hyperglycemia did not correlate with CNFD (P > 0.05), CNBD (P > 0.05), CNFL (P > 0.05) or IWL (P > 0.05). Conclusions Greater GV and duration in hypoglycemia, rather than hyperglycemia, are associated with nerve fiber loss in diabetes.
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Affiliation(s)
- Hoda Gad
- Department of Medicine, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Einas Elgassim
- Department of Medicine, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Ibrahim Mohammed
- Department of Medicine, Weill Cornell Medicine-Qatar, Doha, Qatar
- Department of Internal Medicine, Albany Medical Center Hospital, Albany, New York, USA
| | - Ahmad Yaser Alhaddad
- Department of Mechanical and Industrial Engineering, Qatar University, Doha, Qatar
| | | | - John-John Cabibihan
- Department of Mechanical and Industrial Engineering, Qatar University, Doha, Qatar
| | - Abdulaziz Al-Ali
- KINDI Center for computing research, Qatar University, Doha, Qatar
| | | | - Aliyaa Haji
- Department of Medicine, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Neila Lamine
- Department of Medicine, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Adnan Khan
- Faculty of Healthy Sciences, Khyber Medical University, Peshawar, Pakistan
| | | | | | - Alise Kalteniece
- Institute of Cardiovascular Medicine, University of Manchester, Manchester, UK
| | - Maryam Ferdousi
- Institute of Cardiovascular Medicine, University of Manchester, Manchester, UK
| | - Shazli Azmi
- Institute of Cardiovascular Medicine, University of Manchester, Manchester, UK
| | - Uazman Alam
- Diabetes and Neuropathy Research, Department of Eye and Vision Sciences and Pain Research Institute, Institute of Ageing and Chronic Disease, University of Liverpool and Aintree University Hospital NHS Foundation Trust, Liverpool, UK
- Department of Diabetes and Endocrinology, Royal Liverpool and Broadgreen University NHS Hospital Trust, Liverpool, UK
- Division of Endocrinology, Diabetes and Gastroenterology, University of Manchester, Manchester, UK
| | | | - Amin Jayyousi
- Hamad Medical Corporation, National Diabetes Center, Doha, Qatar
| | - Dabia AlMohanadi
- Hamad Medical Corporation, National Diabetes Center, Doha, Qatar
| | - Khaled Baagar
- Hamad Medical Corporation, National Diabetes Center, Doha, Qatar
| | - Rayaz A Malik
- Department of Medicine, Weill Cornell Medicine-Qatar, Doha, Qatar
- Institute of Cardiovascular Medicine, University of Manchester, Manchester, UK
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14
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Malik RA. Corneal confocal microscopy meets continuous glucose monitoring: a tale of two technologies. Chin Med J (Engl) 2022; 135:1891-1893. [PMID: 36148585 PMCID: PMC9746738 DOI: 10.1097/cm9.0000000000002254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Indexed: 01/26/2023] Open
Affiliation(s)
- Rayaz A. Malik
- Weill Cornell Medicine-Qatar, Qatar Foundation, Education City, Doha, Qatar
- Institute of Cardiovascular Science, University of Manchester, Manchester, UK
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15
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Malik RA. Corneal confocal microscopy for the assessment of diabetic neuropathy and beyond in Brazil. ARQUIVOS DE NEURO-PSIQUIATRIA 2022; 80:767-769. [PMID: 36252583 PMCID: PMC9703882 DOI: 10.1055/s-0042-1756169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Rayaz A. Malik
- Weill Cornell Medicine-Qatar, Education City, Qatar Foundation, Doha, Qatar
- University of Manchester, Division of Cardiovascular Sciences, Manchester, United Kingdom
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16
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Ponirakis G, Al-Janahi I, Elgassim E, Gad H, Petropoulos IN, Khan A, Ali H, Siddique MA, Gul W, Ferdousi M, Kalteniece A, Mohamed FF, Ahmed LH, Dakroury Y, El Shewehy AM, Al-Mohamedi A, AlMarri F, Homssi M, Qazi M, Hadid NH, Al-Khayat F, Mahfoud ZR, Azmi S, Alam U, Zirie MA, Al-Ansari Y, Jayyousi A, Rigby AS, Kilpatrick ES, Atkin SL, Malik RA. Progressive loss of corneal nerve fibers is associated with physical inactivity and glucose lowering medication associated with weight gain in type 2 diabetes. J Diabetes Investig 2022; 13:1703-1710. [PMID: 35652859 PMCID: PMC9533053 DOI: 10.1111/jdi.13864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 04/03/2022] [Accepted: 05/31/2022] [Indexed: 11/30/2022] Open
Abstract
Aims/Introduction Limited studies have identified risk factors linked to the progression of diabetic peripheral neuropathy (DPN) in type 2 diabetes. This study examined the association of risk factors with change in neuropathy measures over 2 years. Materials and Methods Participants with type 2 diabetes (n = 78) and controls (n = 26) underwent assessment of clinical and metabolic parameters and neuropathy using corneal confocal microscopy (CCM), vibration perception threshold (VPT), and the DN4 questionnaire at baseline and 2 year follow‐up. Results Participants with type 2 diabetes had a lower corneal nerve fiber density (CNFD), branch density (CNBD), and fiber length (CNFL) (P ≤ 0.0001) and a higher VPT (P ≤ 0.01) compared with controls. Over 2 years, despite a modest reduction in HbA1c (P ≤ 0.001), body weight (P ≤ 0.05), and LDL (P ≤ 0.05) the prevalence of DPN (P = 0.28) and painful DPN (P = 0.21) did not change, but there was a significant further reduction in CNBD (P ≤ 0.0001) and CNFL (P ≤ 0.05). CNFD, CNBD, and CNFL decreased significantly in physically inactive subjects (P < 0.05–0.0001), whilst there was no change in CNFD (P = 0.07) or CNFL (P = 0.85) in physically active subjects. Furthermore, there was no change in CNFD (P = 0.82), CNBD (P = 0.08), or CNFL (P = 0.66) in patients treated with glucose lowering medication associated with weight loss, whilst CNBD (P = 0.001) decreased in patients on glucose lowering medication associated with weight gain. Conclusions In participants with type 2 diabetes, despite a modest improvement in HbA1c, body weight, and LDL there was a progressive loss of corneal nerve fibers; except in those who were physically active or on glucose lowering medication associated with weight loss.
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Affiliation(s)
- Georgios Ponirakis
- Department of Medicine, Weill Cornell Medicine-Qatar, Qatar Foundation, Doha, Qatar
| | - Ibrahim Al-Janahi
- National Diabetes Center, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar
| | - Einas Elgassim
- Department of Medicine, Weill Cornell Medicine-Qatar, Qatar Foundation, Doha, Qatar
| | - Hoda Gad
- Department of Medicine, Weill Cornell Medicine-Qatar, Qatar Foundation, Doha, Qatar
| | | | - Adnan Khan
- Department of Medicine, Weill Cornell Medicine-Qatar, Qatar Foundation, Doha, Qatar
| | - Hamda Ali
- National Diabetes Center, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar
| | - Mashhood A Siddique
- National Diabetes Center, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar
| | - Wajiha Gul
- National Diabetes Center, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar
| | - Maryam Ferdousi
- Division of Cardiovascular Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Alise Kalteniece
- Division of Cardiovascular Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Fatima Fs Mohamed
- Department of Medicine, Weill Cornell Medicine-Qatar, Qatar Foundation, Doha, Qatar
| | - Lina Hm Ahmed
- Department of Medicine, Weill Cornell Medicine-Qatar, Qatar Foundation, Doha, Qatar
| | - Youssra Dakroury
- Department of Medicine, Weill Cornell Medicine-Qatar, Qatar Foundation, Doha, Qatar
| | - Abeer Mm El Shewehy
- Department of Medicine, Weill Cornell Medicine-Qatar, Qatar Foundation, Doha, Qatar
| | | | - Fatema AlMarri
- Department of Medicine, Weill Cornell Medicine-Qatar, Qatar Foundation, Doha, Qatar
| | - Moayad Homssi
- Department of Medicine, Weill Cornell Medicine-Qatar, Qatar Foundation, Doha, Qatar
| | - Murtaza Qazi
- Department of Medicine, Weill Cornell Medicine-Qatar, Qatar Foundation, Doha, Qatar
| | - Nebras H Hadid
- Department of Medicine, Weill Cornell Medicine-Qatar, Qatar Foundation, Doha, Qatar
| | - Fatima Al-Khayat
- Department of Medicine, Weill Cornell Medicine-Qatar, Qatar Foundation, Doha, Qatar
| | - Ziyad R Mahfoud
- Department of Medicine, Weill Cornell Medicine-Qatar, Qatar Foundation, Doha, Qatar
| | - Shazli Azmi
- Division of Cardiovascular Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK.,Centre for Diabetes, Endocrinology and Metabolism, Manchester University NHS Foundation Trust, Manchester, UK
| | - Uazman Alam
- Department of Cardiovascular & Metabolic Medicine and the Pain Research Institute, Institute of Life Course and Medical Sciences, University of Liverpool, and Liverpool University Hospital NHS Foundation Trust, Liverpool, UK
| | - Mahmoud A Zirie
- National Diabetes Center, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar
| | - Yousuf Al-Ansari
- National Diabetes Center, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar
| | - Amin Jayyousi
- National Diabetes Center, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar
| | - Alan S Rigby
- Centre for Diabetes, Endocrinology and Metabolism, Manchester University NHS Foundation Trust, Manchester, UK.,Hull York Medical School, University of Hull, Kingston Upon Hull, UK
| | - Eric S Kilpatrick
- Division of Cardiovascular Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK.,Centre for Diabetes, Endocrinology and Metabolism, Manchester University NHS Foundation Trust, Manchester, UK.,Hull York Medical School, University of Hull, Kingston Upon Hull, UK
| | - Stephen L Atkin
- Royal College of Surgeons in Ireland Bahrain, Adliya, Kingdom of Bahrain
| | - Rayaz A Malik
- Department of Medicine, Weill Cornell Medicine-Qatar, Qatar Foundation, Doha, Qatar.,Division of Cardiovascular Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK.,Faculty of Science and Engineering, Manchester Metropolitan University, Manchester, UK
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17
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Ponirakis G, Elhadd T, Al Ozairi E, Brema IA, Subitha Chinnaiyan ND, Taghadom E, Al Kandari J, Al Wotayan R, Al Ozairi A, Aljohani N, AlMistehi W, Al Qahtani N, Khan S, Dabbous Z, Siddique MA, Petropoulos IN, Khan A, Almuhannadi H, Ashawesh KAE, Dukhan KM, Mahfoud ZR, Zirie MA, Jayyousi A, Malik RA. Prevalence and risk factors for diabetic peripheral neuropathy, neuropathic pain and foot ulceration in the Arabian Gulf Region. J Diabetes Investig 2022; 13:1551-1559. [PMID: 35445568 PMCID: PMC9434582 DOI: 10.1111/jdi.13815] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 03/26/2022] [Accepted: 04/12/2022] [Indexed: 11/30/2022] Open
Abstract
Aims/Introduction This study determined the prevalence and risk factors for diabetic peripheral neuropathy (DPN), painful DPN and diabetic foot ulceration (DFU) in patients with type 2 diabetes in secondary healthcare in Qatar, Kuwait and the Kingdom of Saudi Arabia. Materials and Methods Adults aged 18–85 years with type 2 diabetes were randomly enrolled from secondary healthcare, and underwent clinical and metabolic assessment. DPN was evaluated using vibration perception threshold and neuropathic symptoms and painful Diabetic Peripheral Neuropathy was evaluated using the Douleur Neuropathique 4 questionnaire. Results A total of 3,021 individuals were recruited between June 2017 and May 2019. The prevalence of DPN was 33.3%, of whom 52.2% were at risk of DFU and 53.6% were undiagnosed. The prevalence of painful DPN was 43.3%, of whom 54.3% were undiagnosed. DFU was present in 2.9%. The adjusted odds ratios for DPN and painful DPN were higher with increasing diabetes duration, obesity, poor glycemic control and hyperlipidemia, and lower with greater physical activity. The adjusted odds ratio for DFU was higher with the presence of DPN, severe loss of vibration perception, hypertension and vitamin D deficiency. Conclusions This is the largest study to date from the Middle East showing a high prevalence of undiagnosed DPN, painful DPN and those at risk of DFU in patients with type 2 diabetes, and identifies their respective risk factors.
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Affiliation(s)
- Georgios Ponirakis
- Deparrment of Medicine, Weill Cornell Medicine-Qatar, Qatar Foundation, Education City, Doha, Qatar
| | - Tarik Elhadd
- National Diabetes Center, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar.,National Diabetes Center, Al-Wakra Hospital, Hamad Medical Corporation, Doha, Qatar
| | - Ebaa Al Ozairi
- Department of Clinical Research, Dasman Diabetes Institute, Kuwait City, Kuwait.,Department of Medicine, Kuwait University, Kuwait City, Kuwait
| | - Imad A Brema
- Obesity Endocrine and Metabolism Center, King Fahad Medical City, Riyadh, Kingdom of Saudi Arabia
| | - N D Subitha Chinnaiyan
- National Diabetes Center, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar
| | - Etab Taghadom
- Department of Clinical Research, Dasman Diabetes Institute, Kuwait City, Kuwait.,Department of Medicine, Kuwait University, Kuwait City, Kuwait
| | - Jumana Al Kandari
- Department of Clinical Research, Dasman Diabetes Institute, Kuwait City, Kuwait.,Department of Medicine, Kuwait University, Kuwait City, Kuwait
| | - Rehab Al Wotayan
- Department of Clinical Research, Dasman Diabetes Institute, Kuwait City, Kuwait.,Department of Medicine, Kuwait University, Kuwait City, Kuwait
| | - Abdulla Al Ozairi
- Department of Clinical Research, Dasman Diabetes Institute, Kuwait City, Kuwait.,Department of Medicine, Kuwait University, Kuwait City, Kuwait
| | - Naji Aljohani
- Obesity Endocrine and Metabolism Center, King Fahad Medical City, Riyadh, Kingdom of Saudi Arabia
| | - Wael AlMistehi
- Obesity Endocrine and Metabolism Center, King Fahad Medical City, Riyadh, Kingdom of Saudi Arabia
| | - Nora Al Qahtani
- Obesity Endocrine and Metabolism Center, King Fahad Medical City, Riyadh, Kingdom of Saudi Arabia
| | - Shawana Khan
- Obesity Endocrine and Metabolism Center, King Fahad Medical City, Riyadh, Kingdom of Saudi Arabia
| | - Zeinab Dabbous
- National Diabetes Center, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar
| | - Mashhood A Siddique
- National Diabetes Center, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar
| | - Ioannis N Petropoulos
- Deparrment of Medicine, Weill Cornell Medicine-Qatar, Qatar Foundation, Education City, Doha, Qatar
| | - Adnan Khan
- Deparrment of Medicine, Weill Cornell Medicine-Qatar, Qatar Foundation, Education City, Doha, Qatar
| | - Hamad Almuhannadi
- National Diabetes Center, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar
| | - Khaled A E Ashawesh
- National Diabetes Center, Al-Wakra Hospital, Hamad Medical Corporation, Doha, Qatar
| | - Khaled M Dukhan
- National Diabetes Center, Al-Wakra Hospital, Hamad Medical Corporation, Doha, Qatar
| | - Ziyad R Mahfoud
- Deparrment of Medicine, Weill Cornell Medicine-Qatar, Qatar Foundation, Education City, Doha, Qatar
| | - Mahmoud A Zirie
- National Diabetes Center, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar
| | - Amin Jayyousi
- National Diabetes Center, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar
| | - Rayaz A Malik
- Deparrment of Medicine, Weill Cornell Medicine-Qatar, Qatar Foundation, Education City, Doha, Qatar.,National Diabetes Center, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar.,Institute of Cardiovascular Science, University of Manchester, Manchester, UK.,Faculty of Science and Engineering, Manchester Metropolitan University, Manchester, UK
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18
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Petropoulos IN, Bitirgen G, Ferdousi M, Kalteniece A, Azmi S, D'Onofrio L, Lim SH, Ponirakis G, Khan A, Gad H, Mohammed I, Mohammadi YE, Malik A, Gosal D, Kobylecki C, Silverdale M, Soran H, Alam U, Malik RA. Corneal Confocal Microscopy to Image Small Nerve Fiber Degeneration: Ophthalmology Meets Neurology. FRONTIERS IN PAIN RESEARCH 2022; 2:725363. [PMID: 35295436 PMCID: PMC8915697 DOI: 10.3389/fpain.2021.725363] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 07/26/2021] [Indexed: 12/13/2022] Open
Abstract
Neuropathic pain has multiple etiologies, but a major feature is small fiber dysfunction or damage. Corneal confocal microscopy (CCM) is a rapid non-invasive ophthalmic imaging technique that can image small nerve fibers in the cornea and has been utilized to show small nerve fiber loss in patients with diabetic and other neuropathies. CCM has comparable diagnostic utility to intraepidermal nerve fiber density for diabetic neuropathy, fibromyalgia and amyloid neuropathy and predicts the development of diabetic neuropathy. Moreover, in clinical intervention trials of patients with diabetic and sarcoid neuropathy, corneal nerve regeneration occurs early and precedes an improvement in symptoms and neurophysiology. Corneal nerve fiber loss also occurs and is associated with disease progression in multiple sclerosis, Parkinson's disease and dementia. We conclude that corneal confocal microscopy has good diagnostic and prognostic capability and fulfills the FDA criteria as a surrogate end point for clinical trials in peripheral and central neurodegenerative diseases.
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Affiliation(s)
| | - Gulfidan Bitirgen
- Department of Ophthalmology, Meram Faculty of Medicine, Necmettin Erbakan University, Konya, Turkey
| | - Maryam Ferdousi
- Faculty of Biology, Medicine and Health, University of Manchester, Cardiovascular Trials Unit, Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Alise Kalteniece
- Faculty of Biology, Medicine and Health, University of Manchester, Cardiovascular Trials Unit, Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Shazli Azmi
- Faculty of Biology, Medicine and Health, University of Manchester, Cardiovascular Trials Unit, Manchester University NHS Foundation Trust, Manchester, United Kingdom.,Centre for Diabetes, Endocrinology and Metabolism, Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Luca D'Onofrio
- Department of Experimental Medicine, Sapienza University, Rome, Italy
| | - Sze Hway Lim
- Department of Neurology, Salford Royal National Health System (NHS) Foundation Trust, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom
| | | | - Adnan Khan
- Department of Medicine, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Hoda Gad
- Department of Medicine, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Ibrahim Mohammed
- Department of Medicine, Weill Cornell Medicine-Qatar, Doha, Qatar
| | | | - Ayesha Malik
- Department of Medicine, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - David Gosal
- Department of Neurology, Salford Royal National Health System (NHS) Foundation Trust, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom
| | - Christopher Kobylecki
- Department of Neurology, Salford Royal National Health System (NHS) Foundation Trust, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom
| | - Monty Silverdale
- Department of Neurology, Salford Royal National Health System (NHS) Foundation Trust, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom
| | - Handrean Soran
- Faculty of Biology, Medicine and Health, University of Manchester, Cardiovascular Trials Unit, Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Uazman Alam
- Department of Cardiovascular and Metabolic Medicine, Clinical Sciences Centre, Pain Research Institute, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool University Hospital National Health System (NHS) Foundation Trust, Liverpool, United Kingdom
| | - Rayaz A Malik
- Department of Medicine, Weill Cornell Medicine-Qatar, Doha, Qatar.,Faculty of Biology, Medicine and Health, University of Manchester, Cardiovascular Trials Unit, Manchester University NHS Foundation Trust, Manchester, United Kingdom
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19
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Al-Bazz DY, Nelson AJ, Burgess J, Petropoulos IN, Nizza J, Marshall A, Brown E, Cuthbertson DJ, Marshall AG, Malik RA, Alam U. Is Nerve Electrophysiology a Robust Primary Endpoint in Clinical Trials of Treatments for Diabetic Peripheral Neuropathy? Diagnostics (Basel) 2022; 12:diagnostics12030731. [PMID: 35328284 PMCID: PMC8947384 DOI: 10.3390/diagnostics12030731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 03/10/2022] [Accepted: 03/11/2022] [Indexed: 12/10/2022] Open
Abstract
There is currently no FDA-approved disease-modifying therapy for diabetic peripheral neuropathy (DPN). Nerve conduction velocity (NCV) is an established primary endpoint of disease-modifying therapies in DPN and clinical trials have been powered with an assumed decline of 0.5 m/s/year. This paper sought to establish the time-dependent change in NCV associated with a placebo, compared to that observed in the active intervention group. A literature search identified twenty-one double-blind, randomised controlled trials in DPN of ≥1 year duration conducted between 1971 and 2021. We evaluated changes in neurophysiology, with a focus on peroneal motor and sural sensory NCV and amplitude in the placebo and treatment groups. There was significant variability in the change and direction of change (reduction/increase) in NCV in the placebo arm, as well as variability influenced by the anatomical site of neurophysiological measurement within a given clinical trial. A critical re-evaluation of efficacy trials should consider placebo-adjusted effects and present the placebo-subtracted change in NCV rather than assume a universal annual decline of 0.5 m/s/year. Importantly, endpoints such as corneal confocal microscopy (CCM) have demonstrated early nerve repair, whilst symptoms and NCV have not changed, and should thus be considered as a viable alternative.
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Affiliation(s)
- Dalal Y. Al-Bazz
- Institute of Life Course and Medical Sciences and the Pain Research Institute, University of Liverpool and Liverpool University Hospital NHS Foundation Trust, Liverpool L9 7AL, UK; (A.J.N.); (J.B.); (J.N.); (A.M.); (A.G.M.)
- Correspondence: (D.Y.A.-B.); or (U.A.); Tel.: +44-151-529-5920 (U.A.)
| | - Andrew J. Nelson
- Institute of Life Course and Medical Sciences and the Pain Research Institute, University of Liverpool and Liverpool University Hospital NHS Foundation Trust, Liverpool L9 7AL, UK; (A.J.N.); (J.B.); (J.N.); (A.M.); (A.G.M.)
| | - Jamie Burgess
- Institute of Life Course and Medical Sciences and the Pain Research Institute, University of Liverpool and Liverpool University Hospital NHS Foundation Trust, Liverpool L9 7AL, UK; (A.J.N.); (J.B.); (J.N.); (A.M.); (A.G.M.)
| | - Ioannis N. Petropoulos
- Research Division, Weill Cornell Medicine-Qatar, Qatar Foundation, Education City, Doha 24144, Qatar; (I.N.P.); (R.A.M.)
| | - Jael Nizza
- Institute of Life Course and Medical Sciences and the Pain Research Institute, University of Liverpool and Liverpool University Hospital NHS Foundation Trust, Liverpool L9 7AL, UK; (A.J.N.); (J.B.); (J.N.); (A.M.); (A.G.M.)
| | - Anne Marshall
- Institute of Life Course and Medical Sciences and the Pain Research Institute, University of Liverpool and Liverpool University Hospital NHS Foundation Trust, Liverpool L9 7AL, UK; (A.J.N.); (J.B.); (J.N.); (A.M.); (A.G.M.)
| | - Emily Brown
- Obesity and Endocrinology Research Group, Institute of Life Course and Medical Sciences, University of Liverpool and Liverpool University Hospital NHS Foundation Trust, Liverpool L9 7AL, UK; (E.B.); (D.J.C.)
| | - Daniel J. Cuthbertson
- Obesity and Endocrinology Research Group, Institute of Life Course and Medical Sciences, University of Liverpool and Liverpool University Hospital NHS Foundation Trust, Liverpool L9 7AL, UK; (E.B.); (D.J.C.)
| | - Andrew G. Marshall
- Institute of Life Course and Medical Sciences and the Pain Research Institute, University of Liverpool and Liverpool University Hospital NHS Foundation Trust, Liverpool L9 7AL, UK; (A.J.N.); (J.B.); (J.N.); (A.M.); (A.G.M.)
- Institute of Cardiovascular Sciences, Cardiac Centre, Faculty of Medical and Human Sciences, University of Manchester and NIHR/Wellcome Trust Clinical Research Facility, Manchester M13 9WL, UK
| | - Rayaz A. Malik
- Research Division, Weill Cornell Medicine-Qatar, Qatar Foundation, Education City, Doha 24144, Qatar; (I.N.P.); (R.A.M.)
- Institute of Cardiovascular Sciences, Cardiac Centre, Faculty of Medical and Human Sciences, University of Manchester and NIHR/Wellcome Trust Clinical Research Facility, Manchester M13 9WL, UK
| | - Uazman Alam
- Institute of Life Course and Medical Sciences and the Pain Research Institute, University of Liverpool and Liverpool University Hospital NHS Foundation Trust, Liverpool L9 7AL, UK; (A.J.N.); (J.B.); (J.N.); (A.M.); (A.G.M.)
- Division of Diabetes, Endocrinology and Gastroenterology, Institute of Human Development, University of Manchester, Manchester M13 9PL, UK
- Correspondence: (D.Y.A.-B.); or (U.A.); Tel.: +44-151-529-5920 (U.A.)
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20
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Zhou T, Lee A, Lo ACY, Kwok JSWJ. Diabetic Corneal Neuropathy: Pathogenic Mechanisms and Therapeutic Strategies. Front Pharmacol 2022; 13:816062. [PMID: 35281903 PMCID: PMC8905431 DOI: 10.3389/fphar.2022.816062] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 01/27/2022] [Indexed: 12/27/2022] Open
Abstract
Diabetes mellitus (DM) is a major global public health problem that can cause complications such as diabetic retinopathy, diabetic neuropathy, and diabetic nephropathy. Besides the reporting of reduction in corneal nerve density and decrease in corneal sensitivity in diabetic patients, there may be a subsequent result in delayed corneal wound healing and increased corneal infections. Despite being a potential cause of blindness, these corneal nerve changes have not gained enough attention. It has been proposed that corneal nerve changes may be an indicator for diabetic neuropathy, which can provide a window for early diagnosis and treatment. In this review, the authors aimed to give an overview of the relationship between corneal nerves and diabetic neuropathy as well as the underlying pathophysiological mechanisms of corneal nerve fiber changes caused by DM for improved prediction and prevention of diabetic neuropathy. In addition, the authors summarized current and novel therapeutic methods for delayed corneal wound healing, nerve protection and regeneration in the diabetic cornea.
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Affiliation(s)
- Ting Zhou
- Department of Ophthalmology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Allie Lee
- Department of Ophthalmology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Amy Cheuk Yin Lo
- Department of Ophthalmology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Jeremy Sze Wai John Kwok
- Department of Ophthalmology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
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21
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Malik RA, Efron N. Corneal Confocal Microscopy and the Nervous System: Introduction to the Special Issue. J Clin Med 2022; 11:jcm11061475. [PMID: 35329801 PMCID: PMC8953792 DOI: 10.3390/jcm11061475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 03/05/2022] [Indexed: 12/07/2022] Open
Affiliation(s)
- Rayaz A. Malik
- Weill Cornell Medicine-Qatar, Research Division, Qatar Foundation, Education City, Doha 24144, Qatar;
| | - Nathan Efron
- School of Optometry and Vision Science, Queensland University of Technology, Kelvin Grove, QLD 4059, Australia
- Correspondence:
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22
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The impact of canagliflozin on the risk of neuropathy events: a post-hoc exploratory analysis of the CREDENCE trial. DIABETES & METABOLISM 2022; 48:101331. [DOI: 10.1016/j.diabet.2022.101331] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 12/29/2021] [Accepted: 02/08/2022] [Indexed: 12/17/2022]
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23
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Bönhof GJ, Herder C, Ziegler D. Diagnostic Tools, Biomarkers, and Treatments in Diabetic polyneuropathy and Cardiovascular Autonomic Neuropathy. Curr Diabetes Rev 2022; 18:e120421192781. [PMID: 33845748 DOI: 10.2174/1573399817666210412123740] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 02/24/2021] [Accepted: 03/02/2021] [Indexed: 11/22/2022]
Abstract
The various manifestations of diabetic neuropathy, including distal symmetric sensorimotor polyneuropathy (DSPN) and cardiovascular autonomic neuropathy (CAN), are among the most prevalent chronic complications of diabetes. Major clinical complications of diabetic neuropathies, such as neuropathic pain, chronic foot ulcers, and orthostatic hypotension, are associated with considerable morbidity, increased mortality, and diminished quality of life. Despite the substantial individual and socioeconomic burden, the strategies to diagnose and treat diabetic neuropathies remain insufficient. This review provides an overview of the current clinical aspects and recent advances in exploring local and systemic biomarkers of both DSPN and CAN assessed in human studies (such as biomarkers of inflammation and oxidative stress) for better understanding of the underlying pathophysiology and for improving early detection. Current therapeutic options for DSPN are (I) causal treatment, including lifestyle modification, optimal glycemic control, and multifactorial risk intervention, (II) pharmacotherapy derived from pathogenetic concepts, and (III) analgesic treatment against neuropathic pain. Recent advances in each category are discussed, including non-pharmacological approaches, such as electrical stimulation. Finally, the current therapeutic options for cardiovascular autonomic complications are provided. These insights should contribute to a broader understanding of the various manifestations of diabetic neuropathies from both the research and clinical perspectives.
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Affiliation(s)
- Gidon J Bönhof
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Department of Endocrinology, Medical Faculty and University Hospital, Heinrich Heine University, Düsseldorf, Germany
| | - Christian Herder
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Department of Endocrinology, Medical Faculty and University Hospital, Heinrich Heine University, Düsseldorf, Germany
- German Center for Diabetes Research, Partner Düsseldorf, München-Neuherberg, Germany
| | - Dan Ziegler
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Department of Endocrinology, Medical Faculty and University Hospital, Heinrich Heine University, Düsseldorf, Germany
- German Center for Diabetes Research, Partner Düsseldorf, München-Neuherberg, Germany
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24
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Perspectives of glycemic variability in diabetic neuropathy: a comprehensive review. Commun Biol 2021; 4:1366. [PMID: 34876671 PMCID: PMC8651799 DOI: 10.1038/s42003-021-02896-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 11/16/2021] [Indexed: 12/14/2022] Open
Abstract
Diabetic neuropathy is one of the most prevalent chronic complications of diabetes, and up to half of diabetic patients will develop diabetic neuropathy during their disease course. Notably, emerging evidence suggests that glycemic variability is associated with the pathogenesis of diabetic complications and has emerged as a possible independent risk factor for diabetic neuropathy. In this review, we describe the commonly used metrics for evaluating glycemic variability in clinical practice and summarize the role and related mechanisms of glycemic variability in diabetic neuropathy, including cardiovascular autonomic neuropathy, diabetic peripheral neuropathy and cognitive impairment. In addition, we also address the potential pharmacological and non-pharmacological treatment methods for diabetic neuropathy, aiming to provide ideas for the treatment of diabetic neuropathy. Zhang et al. describe metrics for evaluating glycaemic variability (GV) in clinical practice and summarize the role and related mechanisms of GV in diabetic neuropathy, including cardiovascular autonomic neuropathy, diabetic peripheral neuropathy and cognitive impairment. They aim to stimulate ideas for the treatment of diabetic neuropathy.
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25
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Ponirakis G, Abdul‐Ghani MA, Jayyousi A, Zirie MA, Al‐Mohannadi S, Almuhannadi H, Petropoulos IN, Khan A, Gad H, Migahid O, Megahed A, Qazi M, AlMarri F, Al‐Khayat F, Mahfoud Z, DeFronzo R, Malik RA. Insulin resistance limits corneal nerve regeneration in patients with type 2 diabetes undergoing intensive glycemic control. J Diabetes Investig 2021; 12:2002-2009. [PMID: 34002953 PMCID: PMC8565403 DOI: 10.1111/jdi.13582] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 03/22/2021] [Accepted: 04/15/2021] [Indexed: 01/04/2023] Open
Abstract
AIMS/INTRODUCTION This study aimed to investigate whether insulin resistance (IR) in individuals with type 2 diabetes undergoing intensive glycemic control determines the extent of improvement in neuropathy. MATERIALS AND METHODS This was an exploratory substudy of an open-label, randomized controlled trial of individuals with poorly controlled type 2 diabetes treated with exenatide and pioglitazone or insulin to achieve a glycated hemoglobin <7.0% (<53 mmol/mol). Baseline IR was defined using homeostasis model assessment of IR, and change in neuropathy was assessed using corneal confocal microscopy. RESULTS A total of 38 individuals with type 2 diabetes aged 50.2 ± 8.5 years with (n = 25, 66%) and without (n = 13, 34%) IR were studied. There was a significant decrease in glycated hemoglobin (P < 0.0001), diastolic blood pressure (P < 0.0001), total cholesterol (P < 0.01) and low-density lipoprotein (P = 0.05), and an increase in bodyweight (P < 0.0001) with treatment. Individuals with homeostasis model assessment of IR <1.9 showed a significant increase in corneal nerve fiber density (P ≤ 0.01), length (P ≤ 0.01) and branch density (P ≤ 0.01), whereas individuals with homeostasis model assessment of IR ≥1.9 showed no change. IR was negatively associated with change in corneal nerve fiber density after adjusting for change in bodyweight (P < 0.05). CONCLUSIONS Nerve regeneration might be limited in individuals with type 2 diabetes and IR undergoing treatment with pioglitazone plus exenatide or insulin to improve glycemic control.
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Affiliation(s)
- Georgios Ponirakis
- Weill Cornell Medicine in QatarQatar FoundationEducation City, DohaQatar
- Faculty of Science and EngineeringManchester Metropolitan UniversityManchesterUK
| | - Muhammad A Abdul‐Ghani
- National Diabetes CenterHamad General HospitalHamad Medical CorporationDohaQatar
- Division of DiabetesUniversity of Texas Health Science CenterSan AntonioTexasUSA
| | - Amin Jayyousi
- National Diabetes CenterHamad General HospitalHamad Medical CorporationDohaQatar
| | - Mahmoud A Zirie
- National Diabetes CenterHamad General HospitalHamad Medical CorporationDohaQatar
| | - Salma Al‐Mohannadi
- Weill Cornell Medicine in QatarQatar FoundationEducation City, DohaQatar
| | - Hamad Almuhannadi
- Weill Cornell Medicine in QatarQatar FoundationEducation City, DohaQatar
| | | | - Adnan Khan
- Weill Cornell Medicine in QatarQatar FoundationEducation City, DohaQatar
| | - Hoda Gad
- Weill Cornell Medicine in QatarQatar FoundationEducation City, DohaQatar
| | - Osama Migahid
- National Diabetes CenterHamad General HospitalHamad Medical CorporationDohaQatar
- Division of DiabetesUniversity of Texas Health Science CenterSan AntonioTexasUSA
| | - Ayman Megahed
- National Diabetes CenterHamad General HospitalHamad Medical CorporationDohaQatar
| | - Murtaza Qazi
- Weill Cornell Medicine in QatarQatar FoundationEducation City, DohaQatar
| | - Fatema AlMarri
- Weill Cornell Medicine in QatarQatar FoundationEducation City, DohaQatar
| | - Fatima Al‐Khayat
- Weill Cornell Medicine in QatarQatar FoundationEducation City, DohaQatar
| | - Ziyad Mahfoud
- Weill Cornell Medicine in QatarQatar FoundationEducation City, DohaQatar
| | - Ralph DeFronzo
- Division of DiabetesUniversity of Texas Health Science CenterSan AntonioTexasUSA
| | - Rayaz A Malik
- Weill Cornell Medicine in QatarQatar FoundationEducation City, DohaQatar
- Faculty of Science and EngineeringManchester Metropolitan UniversityManchesterUK
- National Diabetes CenterHamad General HospitalHamad Medical CorporationDohaQatar
- Institute of Cardiovascular ScienceUniversity of ManchesterManchesterUK
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26
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Perkins BA, Lovblom LE, Lewis EJH, Bril V, Ferdousi M, Orszag A, Edwards K, Pritchard N, Russell A, Dehghani C, Pacaud D, Romanchuk K, Mah JK, Jeziorska M, Marshall A, Shtein RM, Pop-Busui R, Lentz SI, Tavakoli M, Boulton AJM, Efron N, Malik RA. Corneal Confocal Microscopy Predicts the Development of Diabetic Neuropathy: A Longitudinal Diagnostic Multinational Consortium Study. Diabetes Care 2021; 44:2107-2114. [PMID: 34210657 PMCID: PMC8740920 DOI: 10.2337/dc21-0476] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 05/28/2021] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Corneal nerve fiber length (CNFL) has been shown in research studies to identify diabetic peripheral neuropathy (DPN). In this longitudinal diagnostic study, we assessed the ability of CNFL to predict the development of DPN. RESEARCH DESIGN AND METHODS From a multinational cohort of 998 participants with type 1 and type 2 diabetes, we studied the subset of 261 participants who were free of DPN at baseline and completed at least 4 years of follow-up for incident DPN. The predictive validity of CNFL for the development of DPN was determined using time-dependent receiver operating characteristic (ROC) curves. RESULTS A total of 203 participants had type 1 and 58 had type 2 diabetes. Mean follow-up time was 5.8 years (interquartile range 4.2-7.0). New-onset DPN occurred in 60 participants (23%; 4.29 events per 100 person-years). Participants who developed DPN were older and had a higher prevalence of type 2 diabetes, higher BMI, and longer duration of diabetes. The baseline electrophysiology and corneal confocal microscopy parameters were in the normal range but were all significantly lower in participants who developed DPN. The time-dependent area under the ROC curve for CNFL ranged between 0.61 and 0.69 for years 1-5 and was 0.80 at year 6. The optimal diagnostic threshold for a baseline CNFL of 14.1 mm/mm2 was associated with 67% sensitivity, 71% specificity, and a hazard ratio of 2.95 (95% CI 1.70-5.11; P < 0.001) for new-onset DPN. CONCLUSIONS CNFL showed good predictive validity for identifying patients at higher risk of developing DPN ∼6 years in the future.
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Affiliation(s)
- Bruce A Perkins
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada .,Division of Endocrinology and Metabolism, Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Leif Erik Lovblom
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - Evan J H Lewis
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - Vera Bril
- The Ellen and Martin Prosserman Centre for Neuromuscular Diseases, Krembil Neuroscience Centre, Division of Neurology, Department of Medicine, University Health Network, University of Toronto, Toronto, Ontario, Canada
| | | | - Andrej Orszag
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - Katie Edwards
- Queensland University of Technology, Brisbane, Queensland, Australia
| | - Nicola Pritchard
- Queensland University of Technology, Brisbane, Queensland, Australia
| | - Anthony Russell
- University of Queensland, Woolloongabba, Queensland, Australia
| | - Cirous Dehghani
- Queensland University of Technology, Brisbane, Queensland, Australia
| | - Danièle Pacaud
- Alberta Children's Hospital, University of Calgary, Calgary, Alberta, Canada
| | - Kenneth Romanchuk
- Alberta Children's Hospital, University of Calgary, Calgary, Alberta, Canada
| | - Jean K Mah
- Alberta Children's Hospital, University of Calgary, Calgary, Alberta, Canada
| | | | - Andrew Marshall
- Alberta Children's Hospital, University of Calgary, Calgary, Alberta, Canada
| | | | | | | | - Mitra Tavakoli
- University of Manchester, Manchester, U.K.,Diabetes and Vascular Research Centre, NIHR Exeter Clinical Research Facility, University of Exeter Medical School, Exeter, U.K
| | | | - Nathan Efron
- Queensland University of Technology, Brisbane, Queensland, Australia
| | - Rayaz A Malik
- University of Manchester, Manchester, U.K.,Weill Cornell Medicine-Qatar, Doha, Qatar
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27
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Ponirakis G, Abdul‐Ghani MA, Jayyousi A, Zirie MA, Qazi M, Almuhannadi H, Petropoulos IN, Khan A, Gad H, Migahid O, Megahed A, Al‐Mohannadi S, AlMarri F, Al‐Khayat F, Mahfoud Z, Al Hamad H, Ramadan M, DeFronzo R, Malik RA. Painful diabetic neuropathy is associated with increased nerve regeneration in patients with type 2 diabetes undergoing intensive glycemic control. J Diabetes Investig 2021; 12:1642-1650. [PMID: 33714226 PMCID: PMC8409832 DOI: 10.1111/jdi.13544] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/26/2020] [Revised: 02/24/2021] [Accepted: 03/09/2021] [Indexed: 12/13/2022] Open
Abstract
AIMS/INTRODUCTION Painful diabetic peripheral neuropathy (pDPN) is associated with small nerve fiber degeneration and regeneration. This study investigated whether the presence of pDPN might influence nerve regeneration in patients with type 2 diabetes undergoing intensive glycemic control. MATERIALS AND METHODS This exploratory substudy of an open-label randomized controlled trial undertook the Douleur Neuropathique en 4 questionnaire and assessment of electrochemical skin conductance, vibration perception threshold and corneal nerve morphology using corneal confocal microscopy in participants with and without pDPN treated with exenatide and pioglitazone or basal-bolus insulin at baseline and 1-year follow up, and 18 controls at baseline only. RESULTS Participants with type 2 diabetes, with (n = 13) and without (n = 28) pDPN had comparable corneal nerve fiber measures, electrochemical skin conductance and vibration perception threshold at baseline, and pDPN was not associated with the severity of DPN. There was a significant glycated hemoglobin reduction (P < 0.0001) and weight gain (P < 0.005), irrespective of therapy. Participants with pDPN showed a significant increase in corneal nerve fiber density (P < 0.05), length (P < 0.0001) and branch density (P < 0.005), and a decrease in the Douleur Neuropathique en 4 score (P < 0.01), but no change in electrochemical skin conductance or vibration perception threshold. Participants without pDPN showed a significant increase in corneal nerve branch density (P < 0.01) and no change in any other neuropathy measures. A change in the severity of painful symptoms was not associated with corneal nerve regeneration and medication for pain. CONCLUSIONS This study showed that intensive glycemic control is associated with greater corneal nerve regeneration and an improvement in the severity of pain in patients with painful diabetic neuropathy.
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Affiliation(s)
- Georgios Ponirakis
- Weill Cornell Medicine‐QatarQatar FoundationEducation CityDohaQatar
- Faculty of Science and EngineeringManchester Metropolitan UniversityManchesterUK
| | - Muhammad A Abdul‐Ghani
- National Diabetes CenterHamad General HospitalHamad Medical CorporationDohaQatar
- Division of DiabetesUniversity of Texas Health Science CenterSan AntonioTexasUSA
| | - Amin Jayyousi
- National Diabetes CenterHamad General HospitalHamad Medical CorporationDohaQatar
| | - Mahmoud A Zirie
- National Diabetes CenterHamad General HospitalHamad Medical CorporationDohaQatar
| | - Murtaza Qazi
- Weill Cornell Medicine‐QatarQatar FoundationEducation CityDohaQatar
| | | | | | - Adnan Khan
- Weill Cornell Medicine‐QatarQatar FoundationEducation CityDohaQatar
| | - Hoda Gad
- Weill Cornell Medicine‐QatarQatar FoundationEducation CityDohaQatar
| | - Osama Migahid
- National Diabetes CenterHamad General HospitalHamad Medical CorporationDohaQatar
- Division of DiabetesUniversity of Texas Health Science CenterSan AntonioTexasUSA
| | - Ayman Megahed
- National Diabetes CenterHamad General HospitalHamad Medical CorporationDohaQatar
| | | | - Fatema AlMarri
- Weill Cornell Medicine‐QatarQatar FoundationEducation CityDohaQatar
| | - Fatima Al‐Khayat
- Weill Cornell Medicine‐QatarQatar FoundationEducation CityDohaQatar
| | - Ziyad Mahfoud
- Weill Cornell Medicine‐QatarQatar FoundationEducation CityDohaQatar
| | | | | | - Ralph DeFronzo
- Division of DiabetesUniversity of Texas Health Science CenterSan AntonioTexasUSA
| | - Rayaz A Malik
- Weill Cornell Medicine‐QatarQatar FoundationEducation CityDohaQatar
- Faculty of Science and EngineeringManchester Metropolitan UniversityManchesterUK
- National Diabetes CenterHamad General HospitalHamad Medical CorporationDohaQatar
- Institute of Cardiovascular ScienceUniversity of ManchesterManchesterUK
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Britten-Jones AC, Kamel JT, Roberts LJ, Braat S, Craig JP, MacIsaac RJ, Downie LE. Investigating the Neuroprotective Effect of Oral Omega-3 Fatty Acid Supplementation in Type 1 Diabetes (nPROOFS1): A Randomized Placebo-Controlled Trial. Diabetes 2021; 70:1794-1806. [PMID: 33952620 DOI: 10.2337/db21-0136] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 04/29/2021] [Indexed: 11/13/2022]
Abstract
This randomized, double-masked, placebo-controlled trial evaluated the effects of oral omega-3 (n-3) fatty acid supplementation on peripheral nerves in type 1 diabetes. Participants with type 1 diabetes were assigned (1:1) to n-3 (1,800 mg/day fish oil) or placebo (600 mg/day olive oil) supplements for 180 days. The primary outcome was change from baseline in central corneal nerve fiber length (CNFL) at day 180. Secondary outcomes included change in other corneal nerve parameters, corneal sensitivity, peripheral small and large nerve fiber function, and ocular surface measures. Efficacy was analyzed according to the intention-to-treat principle. Safety assessments included diabetic retinopathy grade and adverse events. Between July 2017 and September 2019, 43 participants received n-3 (n = 21) or placebo (n = 22) supplements. All participants, except for two assigned to placebo, completed the trial. At day 180, the estimated increase in CNFL in the n-3 group, compared with placebo, was 2.70 mm/mm2 (95% CI 1.64, 3.75). The Omega-3 Index increased relative to placebo (3.3% [95% CI 2.4, 4.2]). There were no differences in most small or large nerve fiber functional parameters. Adverse events were similar between groups. In conclusion, we found in this randomized controlled trial that long-chain n-3 supplements impart corneal neuroregenerative effects in type 1 diabetes, indicating a role in modulating peripheral nerve health.
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Affiliation(s)
| | - Jordan T Kamel
- Department of Medicine, University of Melbourne, Fitzroy, Australia
- Centre for Clinical Neurosciences and Neurological Research, St. Vincent's Hospital Melbourne, Fitzroy, Australia
| | - Leslie J Roberts
- Department of Medicine, University of Melbourne, Fitzroy, Australia
- Centre for Clinical Neurosciences and Neurological Research, St. Vincent's Hospital Melbourne, Fitzroy, Australia
| | - Sabine Braat
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne, Parkville, Australia
- Methods and Implementation Support for Clinical Health research platform, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, Australia
| | - Jennifer P Craig
- Department of Ophthalmology, New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand
| | - Richard J MacIsaac
- Department of Medicine, University of Melbourne, Fitzroy, Australia
- Department of Endocrinology and Diabetes, St. Vincent's Hospital Melbourne, Fitzroy, Australia
| | - Laura E Downie
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, Australia
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Zhang Y, Fan D, Zhang Y, Zhang S, Wang H, Liu Z, Wang H. Using corneal confocal microscopy to compare Mecobalamin intramuscular injections vs oral tablets in treating diabetic peripheral neuropathy: a RCT. Sci Rep 2021; 11:14697. [PMID: 34282267 PMCID: PMC8290034 DOI: 10.1038/s41598-021-94284-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 06/18/2021] [Indexed: 02/04/2023] Open
Abstract
This randomized controlled study used corneal confocal microscopy (CCM) to compare the efficacy of Mecobalamin intramuscular injections vs oral tablets in treating mild to moderate diabetic peripheral neuropathy (DPN) by detecting early nerve fiber repair. Enrolled patients were randomized approximately 1:1 to receive Mecobalamin intramuscular injections (0.5 mg/day, 3 times/week) or Mecobalamin oral tablets (1.5 mg/day) for 8 weeks. Primary outcome was change of inferior whorl length (IWL) from baseline. Secondary outcomes included changes of corneal nerve fibre length (CNFL), corneal nerve fibre density (CNFD), corneal nerve branch density (CNBD) and the Survey of Autonomic Symptoms (SAS). 15 (93.75%) patients in the injection group and 17 (89.47%) patients in the tablet group completed the study. The injection treatment significantly improved patients' IWL from baseline (21.64 ± 3.00 mm/mm2 vs 17.64 ± 4.83 mm/mm2, P < 0.01) while the tablet treatment didn't. Additionally, the injection treatment led to significantly improved CNFL, CNBD and SAS from baseline (all P < 0.05) while the tablet treatment did not. No patient experienced any adverse events. In conclusion, CCM is sensitive enough to detect the superior efficacy of 8-week Mecobalamin intramuscular injection treatment for DPN compared to the oral tablet treatment.ClinicalTrials.gov registration number: NCT04372316 (30/04/2020).
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Affiliation(s)
- Yuanjin Zhang
- Neurology Department, Peking University Third Hospital, 49 North Garden Rd., Haidian District, Beijing, 100191, China
- Beijing Municipal Key Laboratory of Biomarker and Translational Research in Neurodegenerative Disease, Beijing, China
| | - Dongsheng Fan
- Neurology Department, Peking University Third Hospital, 49 North Garden Rd., Haidian District, Beijing, 100191, China.
- Beijing Municipal Key Laboratory of Biomarker and Translational Research in Neurodegenerative Disease, Beijing, China.
| | - Yixuan Zhang
- Neurology Department, Peking University Third Hospital, 49 North Garden Rd., Haidian District, Beijing, 100191, China
- Beijing Municipal Key Laboratory of Biomarker and Translational Research in Neurodegenerative Disease, Beijing, China
| | - Shuo Zhang
- Neurology Department, Peking University Third Hospital, 49 North Garden Rd., Haidian District, Beijing, 100191, China
- Beijing Municipal Key Laboratory of Biomarker and Translational Research in Neurodegenerative Disease, Beijing, China
| | - Haikun Wang
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China
| | - Ziyuan Liu
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China
| | - Hongli Wang
- Neurology Department, Peking University Third Hospital, 49 North Garden Rd., Haidian District, Beijing, 100191, China
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30
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Petropoulos IN, Ponirakis G, Ferdousi M, Azmi S, Kalteniece A, Khan A, Gad H, Bashir B, Marshall A, Boulton AJM, Soran H, Malik RA. Corneal Confocal Microscopy: A Biomarker for Diabetic Peripheral Neuropathy. Clin Ther 2021; 43:1457-1475. [PMID: 33965237 DOI: 10.1016/j.clinthera.2021.04.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 04/05/2021] [Accepted: 04/08/2021] [Indexed: 02/08/2023]
Abstract
PURPOSE Diagnosing early diabetic peripheral neuropathy remains a challenge due to deficiencies in currently advocated end points. The cornea is densely innervated with small sensory fibers, which are structurally and functionally comparable to intraepidermal nerve fibers. Corneal confocal microscopy is a method for rapid, noninvasive scanning of the living cornea with high resolution and magnification. METHODS This narrative review presents the framework for the development of biomarkers and the literature on the use and adoption of corneal confocal microscopy as an objective, diagnostic biomarker in experimental and clinical studies of diabetic peripheral neuropathy. A search was performed on PubMed and Google Scholar based on the terms "corneal confocal microscopy," "diabetic neuropathy," "corneal sensitivity," and "clinical trials." FINDINGS A substantial body of evidence underpins the thesis that corneal nerve loss predicts incident neuropathy and progresses with the severity of diabetic peripheral neuropathy. Corneal confocal microscopy also identifies early corneal nerve regeneration, strongly arguing for its inclusion as a surrogate end point in clinical trials of disease-modifying therapies. IMPLICATIONS There are sufficient diagnostic and prospective validation studies to fulfill the US Food and Drug Administration criteria for a biomarker to support the inclusion of corneal confocal microscopy as a primary end point in clinical trials of disease-modifying therapies in diabetic neuropathy.
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Affiliation(s)
| | | | - Maryam Ferdousi
- Faculty of Biology, Medicine and Health, University of Manchester, Cardiovascular Trials Unit, Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Shazli Azmi
- Faculty of Biology, Medicine and Health, University of Manchester, Cardiovascular Trials Unit, Manchester University NHS Foundation Trust, Manchester, United Kingdom; Centre for Diabetes, Endocrinology and Metabolism, Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Alise Kalteniece
- Faculty of Biology, Medicine and Health, University of Manchester, Cardiovascular Trials Unit, Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Adnan Khan
- Research Division, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Hoda Gad
- Research Division, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Bilal Bashir
- Centre for Diabetes, Endocrinology and Metabolism, Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Andrew Marshall
- Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, United Kingdom; Clinical Neurophysiology, The Walton Centre, Liverpool, United Kingdom; Division of Neuroscience and Experimental Psychology, Faculty of Medical and Human Sciences, University of Manchester, Manchester, United Kingdom
| | - Andrew J M Boulton
- Faculty of Biology, Medicine and Health, University of Manchester, Cardiovascular Trials Unit, Manchester University NHS Foundation Trust, Manchester, United Kingdom; Centre for Diabetes, Endocrinology and Metabolism, Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Handrean Soran
- Faculty of Biology, Medicine and Health, University of Manchester, Cardiovascular Trials Unit, Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Rayaz A Malik
- Research Division, Weill Cornell Medicine-Qatar, Doha, Qatar; Faculty of Biology, Medicine and Health, University of Manchester, Cardiovascular Trials Unit, Manchester University NHS Foundation Trust, Manchester, United Kingdom.
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31
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Ferdousi M, Kalteniece A, Azmi S, Petropoulos IN, Ponirakis G, Alam U, Asghar O, Marshall A, Fullwood C, Jeziorska M, Abbott C, Lauria G, Faber CG, Soran H, Efron N, Boulton AJM, Malik RA. Diagnosis of Neuropathy and Risk Factors for Corneal Nerve Loss in Type 1 and Type 2 Diabetes: A Corneal Confocal Microscopy Study. Diabetes Care 2021; 44:150-156. [PMID: 33144353 PMCID: PMC7783929 DOI: 10.2337/dc20-1482] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 09/23/2020] [Indexed: 02/03/2023]
Abstract
OBJECTIVE To assess the diagnostic utility of corneal confocal microscopy (CCM) for diabetic peripheral neuropathy (DPN) and the risk factors for corneal nerve loss. RESEARCH DESIGN AND METHODS A total of 490 participants, including 72 healthy control subjects, 149 with type 1 diabetes, and 269 with type 2 diabetes, underwent detailed assessment of peripheral neuropathy and CCM in relation to risk factors. RESULTS Corneal nerve fiber density (CNFD) (P < 0.0001 and P < 0.0001), corneal nerve fiber branch density (CNBD) (P < 0.0001 and P < 0.0001), and corneal nerve fiber length (CNFL) (P < 0.0001 and P = 0.02) were significantly lower in patients with type 1 and type 2 diabetes compared with control subjects. CNFD (P < 0.0001), CNBD (P < 0.0001), and CNFL (P < 0.0001) were lower in type 1 diabetes compared with type 2 diabetes. Receiver operating characteristic curve analysis for the diagnosis of DPN demonstrated a good area under the curve for CNFD of 0.81, CNBD of 0.74, and CNFL of 0.73. Multivariable regression analysis showed a significant association among reduced CNFL with age (β = -0.27, P = 0.007), HbA1c (β = -1.1; P = 0.01), and weight (β = -0.14; P = 0.03) in patients with type 2 diabetes and with duration of diabetes (β = -0.13; P = 0.02), LDL cholesterol (β = 1.8, P = 0.04), and triglycerides (β = -2.87; P = 0.009) in patients with type 1 diabetes. CONCLUSIONS CCM identifies more severe corneal nerve loss in patients with type 1 diabetes compared with type 2 diabetes and shows good diagnostic accuracy for DPN. Furthermore, the risk factors for a reduction in corneal nerve fiber length differ between type 1 and type 2 diabetes.
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Affiliation(s)
- Maryam Ferdousi
- Institute of Cardiovascular Sciences, Cardiac Centre, Faculty of Medical and Human Sciences, The University of Manchester and NIHR/Wellcome Trust Clinical Research Facility, Manchester, U.K
| | - Alise Kalteniece
- Institute of Cardiovascular Sciences, Cardiac Centre, Faculty of Medical and Human Sciences, The University of Manchester and NIHR/Wellcome Trust Clinical Research Facility, Manchester, U.K
| | - Shazli Azmi
- Institute of Cardiovascular Sciences, Cardiac Centre, Faculty of Medical and Human Sciences, The University of Manchester and NIHR/Wellcome Trust Clinical Research Facility, Manchester, U.K
| | - Ioannis N Petropoulos
- Research Division, Weill Cornell Medicine-Qatar, Qatar Foundation, Education City, Doha, Qatar
| | - Georgios Ponirakis
- Research Division, Weill Cornell Medicine-Qatar, Qatar Foundation, Education City, Doha, Qatar
| | - Uazman Alam
- Department of Cardiovascular and Metabolic Medicine, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, U.K
| | - Omar Asghar
- Institute of Cardiovascular Sciences, Cardiac Centre, Faculty of Medical and Human Sciences, The University of Manchester and NIHR/Wellcome Trust Clinical Research Facility, Manchester, U.K
| | - Andrew Marshall
- Institute of Cardiovascular Sciences, Cardiac Centre, Faculty of Medical and Human Sciences, The University of Manchester and NIHR/Wellcome Trust Clinical Research Facility, Manchester, U.K
| | - Catherine Fullwood
- Centre for Biostatistics, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, U.K.,Research and Innovation, Manchester University NHS Foundation Trust, Manchester, U.K.,Manchester Academic Health Science Centre, Manchester, U.K
| | - Maria Jeziorska
- Institute of Cardiovascular Sciences, Cardiac Centre, Faculty of Medical and Human Sciences, The University of Manchester and NIHR/Wellcome Trust Clinical Research Facility, Manchester, U.K
| | - Caroline Abbott
- Research Centre for Musculoskeletal Science and Sports Medicine, Department of Life Sciences, Faculty of Science and Engineering, Manchester Metropolitan University, Manchester, U.K
| | - Giuseppe Lauria
- IRCCS Foundation "Carlo Besta" Neurological Institute, Milan, Italy
| | - Catharina G Faber
- Department of Neurology, School for Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Handrean Soran
- Institute of Cardiovascular Sciences, Cardiac Centre, Faculty of Medical and Human Sciences, The University of Manchester and NIHR/Wellcome Trust Clinical Research Facility, Manchester, U.K
| | - Nathan Efron
- Queensland University of Technology, School of Optometry and Vision Science, Brisbane, Queensland, Australia
| | - Andrew J M Boulton
- Institute of Cardiovascular Sciences, Cardiac Centre, Faculty of Medical and Human Sciences, The University of Manchester and NIHR/Wellcome Trust Clinical Research Facility, Manchester, U.K
| | - Rayaz A Malik
- Institute of Cardiovascular Sciences, Cardiac Centre, Faculty of Medical and Human Sciences, The University of Manchester and NIHR/Wellcome Trust Clinical Research Facility, Manchester, U.K. .,Research Division, Weill Cornell Medicine-Qatar, Qatar Foundation, Education City, Doha, Qatar
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32
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Didangelos T, Karlafti E, Kotzakioulafi E, Kontoninas Z, Margaritidis C, Giannoulaki P, Kantartzis K. Efficacy and Safety of the Combination of Superoxide Dismutase, Alpha Lipoic Acid, Vitamin B12, and Carnitine for 12 Months in Patients with Diabetic Neuropathy. Nutrients 2020; 12:nu12113254. [PMID: 33114210 PMCID: PMC7690794 DOI: 10.3390/nu12113254] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Revised: 10/18/2020] [Accepted: 10/20/2020] [Indexed: 02/07/2023] Open
Abstract
Aim: To investigate the efficacy of Superoxide Dismutase, Alpha Lipoic Acid, Acetyl L-Carnitine, and Vitamin B12 (B12) in one tablet in Diabetic Neuropathy (DN). Patients–methods: In this prospective, double-blind, placebo-controlled study, 85 patients with Diabetes Mellitus Type 2 (DMT2) were randomly assigned, either to receive the combination of four elements (active group, n = 43), or placebo (n = 42) for 12 months. We used the Michigan Neuropathy Screening Instrument Questionnaire and Examination (MNSIQ and MNSIE), measured the vibration perception threshold (BIO), and Cardiovascular Autonomic Reflex Tests (CARTs). Nerve function was assessed by DPN Check [sural nerve conduction velocity (SNCV) and amplitude (SNAP)]. Pain (PS) and quality of life (QL) questionnaires were administered. Results: At follow-up, BIO, MNSIQ, QL, PAIN, and SNCV, SNAP, and B12 levels had significantly improved inactive group (p < 0.001, p < 0.001, p < 0.001, p < 0.001, p = 0.027, p = 0.031, and p < 0.001 respectively), whereas the inplacebo group MCR (mean circular resultant) and PAIN deteriorated (p < 0.001, p < 0.001). The changes in MNSIQ, QL, SNCV, BIO, and PAIN differed significantly between groups (p < 0.001, p < 0.001, p = 0.031, p < 0.001, and p < 0.001 respectively). Conclusions: The combination of the four elements in one tablet for 12 months in patients with DMT2 improved all indices of peripheral neuropathy, including SNAP and SNCV, pain, and Quality of Life perception, except CARTs and MNSIE.
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Affiliation(s)
- Triantafyllos Didangelos
- Diabetes Center, 1st Propaedeutic Department of Internal Medicine, Medical School, University General Hospital of Thessaloniki AHEPA, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece; (E.K.); (E.K.); (Z.K.); (C.M.)
- Correspondence: or ; Tel.: +30-6944863803
| | - Eleni Karlafti
- Diabetes Center, 1st Propaedeutic Department of Internal Medicine, Medical School, University General Hospital of Thessaloniki AHEPA, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece; (E.K.); (E.K.); (Z.K.); (C.M.)
| | - Evangelia Kotzakioulafi
- Diabetes Center, 1st Propaedeutic Department of Internal Medicine, Medical School, University General Hospital of Thessaloniki AHEPA, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece; (E.K.); (E.K.); (Z.K.); (C.M.)
| | - Zisis Kontoninas
- Diabetes Center, 1st Propaedeutic Department of Internal Medicine, Medical School, University General Hospital of Thessaloniki AHEPA, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece; (E.K.); (E.K.); (Z.K.); (C.M.)
| | - Charalampos Margaritidis
- Diabetes Center, 1st Propaedeutic Department of Internal Medicine, Medical School, University General Hospital of Thessaloniki AHEPA, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece; (E.K.); (E.K.); (Z.K.); (C.M.)
| | - Parthena Giannoulaki
- Department of Nutrition and Dietetics, University General Hospital of Thessaloniki AHEPA, 54636 Thessaloniki, Greece;
| | - Konstantinos Kantartzis
- Department of Internal Medicine IV, Division of Endocrinology, Diabetology and Nephrology, University of Tübingen, 72076 Tübingen, Germany;
- Institute for Diabetes Research and Metabolic Diseases (IDM) of the Helmholtz Centre Munich at the University of Tübingen, 72076 Tübingen, Germany
- German Center for Diabetes Research (DZD), 72076 Tübingen, Germany
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33
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Ponirakis G, Elhadd T, Chinnaiyan S, Hamza AH, Sheik S, Kalathingal MA, Anodiyil MS, Dabbous Z, Siddique MA, Almuhannadi H, Petropoulos IN, Khan A, Ae Ashawesh K, Dukhan KM, Mahfoud ZR, Zirie MA, Jayyousi A, Murgatroyd C, Slevin M, Malik RA. Prevalence and risk factors for diabetic neuropathy and painful diabetic neuropathy in primary and secondary healthcare in Qatar. J Diabetes Investig 2020; 12:592-600. [PMID: 32799429 PMCID: PMC8015833 DOI: 10.1111/jdi.13388] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 08/06/2020] [Accepted: 08/10/2020] [Indexed: 02/07/2023] Open
Abstract
Aims/Introduction This study determined the prevalence and risk factors for diabetic peripheral neuropathy (DPN) and painful DPN (pDPN) in patients with type 2 diabetes in primary healthcare (PHC) and secondary healthcare (SHC) in Qatar. Materials and Methods This was a cross‐sectional multicenter study. Adults with type 2 diabetes were randomly enrolled from four PHC centers and two diabetes centers in SHC in Qatar. Participants underwent assessment of clinical and metabolic parameters, DPN and pDPN. Results A total of 1,386 individuals with type 2 diabetes (297 from PHC and 1,089 from SHC) were recruited. The prevalence of DPN (14.8% vs 23.9%, P = 0.001) and pDPN (18.1% vs 37.5%, P < 0.0001) was significantly lower in PHC compared with SHC, whereas those with DPN at high risk for diabetic foot ulceration (31.8% vs 40.0%, P = 0.3) was comparable. The prevalence of undiagnosed DPN (79.5% vs 82.3%, P = 0.66) was comparably high, but undiagnosed pDPN (24.1% vs 71.5%, P < 0.0001) was lower in PHC compared with SHC. The odds of DPN and pDPN increased with age and diabetes duration, and DPN increased with poor glycemic control, hyperlipidemia and hypertension, whereas pDPN increased with obesity and reduced physical activity. Conclusions The prevalence of DPN and pDPN in type 2 diabetes is lower in PHC compared with SHC, and is attributed to overall better control of risk factors and referral bias due to patients with poorly managed complications being referred to SHC. However, approximately 80% of patients had not been previously diagnosed with DPN in PHC and SHC. Furthermore, we identified a number of modifiable risk factors for PDN and pDPN.
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Affiliation(s)
- Georgios Ponirakis
- Weill Cornell Medicine-Qatar, Qatar Foundation, Education City, Doha, Qatar.,Faculty of Science and Engineering, Manchester Metropolitan University, Manchester, UK
| | - Tarik Elhadd
- National Diabetes Center, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar.,National Diabetes Center, Al-Wakra Hospital, Hamad Medical Corporation, Doha, Qatar
| | - Subitha Chinnaiyan
- National Diabetes Center, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar
| | - Abdul H Hamza
- Umm Ghuwailina Primary Health Care, Umm Ghuwailina, Qatar
| | | | | | | | - Zeinab Dabbous
- National Diabetes Center, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar
| | - Mashhood A Siddique
- National Diabetes Center, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar
| | - Hamad Almuhannadi
- Weill Cornell Medicine-Qatar, Qatar Foundation, Education City, Doha, Qatar
| | | | - Adnan Khan
- Weill Cornell Medicine-Qatar, Qatar Foundation, Education City, Doha, Qatar
| | - Khaled Ae Ashawesh
- National Diabetes Center, Al-Wakra Hospital, Hamad Medical Corporation, Doha, Qatar
| | - Khaled M Dukhan
- National Diabetes Center, Al-Wakra Hospital, Hamad Medical Corporation, Doha, Qatar
| | - Ziyad R Mahfoud
- Weill Cornell Medicine-Qatar, Qatar Foundation, Education City, Doha, Qatar
| | - Mahmoud A Zirie
- National Diabetes Center, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar
| | - Amin Jayyousi
- National Diabetes Center, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar
| | | | - Mark Slevin
- Faculty of Science and Engineering, Manchester Metropolitan University, Manchester, UK
| | - Rayaz A Malik
- Weill Cornell Medicine-Qatar, Qatar Foundation, Education City, Doha, Qatar.,Faculty of Science and Engineering, Manchester Metropolitan University, Manchester, UK.,National Diabetes Center, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar.,Institute of Cardiovascular Science, University of Manchester, Manchester, UK
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34
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Andreasen LJ, Kirk RK, Fledelius C, Yorek MA, Lykkesfeldt J, Akerstrom T. Insulin Treatment Attenuates Small Nerve Fiber Damage in Rat Model of Type 2 Diabetes. J Diabetes Res 2020; 2020:9626398. [PMID: 32832565 PMCID: PMC7424504 DOI: 10.1155/2020/9626398] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 07/06/2020] [Indexed: 12/22/2022] Open
Abstract
INTRODUCTION Current clinical guidelines for management of diabetic peripheral neuropathy (DPN) emphasize good glycemic control. However, this has limited effect on prevention of DPN in type 2 diabetic (T2D) patients. This study investigates the effect of insulin treatment on development of DPN in a rat model of T2D to assess the underlying causes leading to DPN. METHODS Twelve-week-old male Sprague-Dawley rats were allocated to a normal chow diet or a 45% kcal high-fat diet. After eight weeks, the high-fat fed animals received a mild dose of streptozotocin to induce hyperglycemia. Four weeks after diabetes induction, the diabetic animals were allocated into three treatment groups receiving either no insulin or insulin-releasing implants in a high or low dose. During the 12-week treatment period, blood glucose and body weight were monitored weekly, whereas Hargreaves' test was performed four, eight, and 12 weeks after treatment initiation. At study termination, several blood parameters, body composition, and neuropathy endpoints were assessed. RESULTS Insulin treatment lowered blood glucose in a dose-dependent manner. In addition, both doses of insulin lowered lipids and increased body fat percentage. High-dose insulin treatment attenuated small nerve fiber damage assessed by Hargreaves' test and intraepidermal nerve fiber density compared to untreated diabetes and low-dose insulin; however, neuropathy was not completely prevented by tight glycemic control. Linear regression analysis revealed that glycemic status, circulating lipids, and sciatic nerve sorbitol level were all negatively associated with the small nerve fiber damage observed. CONCLUSION In summary, our data suggest that high-dose insulin treatment attenuates small nerve fiber damage. Furthermore, data also indicate that both poor glycemic control and dyslipidemia are associated with disease progression. Consequently, this rat model of T2D seems to fit well with progression of DPN in humans and could be a relevant preclinical model to use in relation to research investigating treatment opportunities for DPN.
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Affiliation(s)
- Laura J. Andreasen
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 1870 Frederiksberg, Denmark
- Global Drug Discovery, Novo Nordisk A/S, 2760 Måløv, Denmark
| | - Rikke K. Kirk
- Global Drug Discovery, Novo Nordisk A/S, 2760 Måløv, Denmark
| | | | - Mark A. Yorek
- Department of Veterans Affairs Iowa City Health Care System, Iowa City, IA 52246, USA
| | - Jens Lykkesfeldt
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 1870 Frederiksberg, Denmark
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