Diabetic macular edema associated with glitazone use

Diabetic Disease of the Eye in Canada: Consensus Statements from a Retina Specialist Working Group

Despite advances in systemic care, diabetic disease of the eye (DDE) remains the leading cause of blindness worldwide. There is a critical gap of up-to-date, evidence-based guidance for ophthalmologists in Canada that includes evidence from recent randomized controlled trials. Previous guidance has not always given special consideration to applying treatments and managing DDE in the context of the healthcare system. This consensus statement aims to assist practitioners in the field by providing a spectrum of acceptable opinions on DDE treatment and management from recognized experts in the field. In compiling evidence and generating consensus, a working group of retinal specialists in Canada addressed clinical questions surrounding the four themes of disease, patient, management, and collaboration. The working group reviewed literature representing the highest level of evidence on DDE and shared their opinions on topics surrounding the epidemiology and pathophysiology of diabetic retinopathy and diabetic macular edema; diagnosis and monitoring; considerations around diabetes medication use; strategic considerations for management given systemic comorbidities, ocular comorbidities, and pregnancy; treatment goals and modalities for diabetic macular edema, non-proliferative and proliferative diabetic retinopathy, and retinal detachment; and interdisciplinary collaboration. Ultimately, this work highlighted that the retinal examination in DDE not only informs the treating ophthalmologist but can serve as a global index for disease progression across many tissues of the body. It highlighted further that DDE can be treated regardless of diabetic control, that a systemic approach to patient care will result in the best health outcomes, and prevention of visual complications requires a multidisciplinary management approach. Ophthalmologists must tailor their clinical approach to the needs and circumstances of individual patients and work within the realities of their healthcare setting.

Etiology of Drug-Induced Edema: A Review of Dihydropyridine, Thiazolidinedione, and Other Medications Causing Edema

Edema is an accumulation of fluid in the body's tissues that affects millions of Americans yearly. It can affect multiple body parts, for example, the brain or eyes, but often occurs in the periphery, including the feet and legs. Medications, such as dihydropyridine and thiazolidinediones (TZDs), can be the etiology of edema. Edema can develop in association with problems in the vasculature or lymphatic flow. In recent years, a better understanding of these drug-induced mechanisms has been appreciated. Specifically, dihydropyridines can increase hydrostatic pressure and cause selective pre-capillary vessel vasodilation. TZDs can cause edema through increased vascular permeability and increased hydrostatic pressure. Specifically, peroxisome proliferator-activated receptor gamma (PPARγ) stimulation increases vascular endothelial permeability, vascular endothelial growth factor (VEGF) secretion, renal sodium, and fluid retention. Other drugs that can cause edema include neuropathic pain agents, dopamine agonists, antipsychotics, nitrates, nonsteroidal anti-inflammatory (NSAIDS), steroids, angiotensin-converting enzyme (ACE) inhibitors, and insulin. There are various clinical presentations of edema. Since multiple mechanisms can induce edema, it is important to understand the basic mechanisms and pathophysiology of drug-induced edema. Edema can even become fatal. For example, angioedema can occur from ACE inhibitor therapy. In this regard, it is considered a medical emergency when there is laryngeal involvement. This review aims to thoroughly appreciate the multiple causes of drug-induced edema and the ways it can be treated or prevented.

Treating the Side Effects of Exogenous Glucocorticoids; Can We Separate the Good From the Bad?

It is estimated that 2% to 3% of the population are currently prescribed systemic or topical glucocorticoid treatment. The potent anti-inflammatory action of glucocorticoids to deliver therapeutic benefit is not in doubt. However, the side effects associated with their use, including central weight gain, hypertension, insulin resistance, type 2 diabetes (T2D), and osteoporosis, often collectively termed iatrogenic Cushing's syndrome, are associated with a significant health and economic burden. The precise cellular mechanisms underpinning the differential action of glucocorticoids to drive the desirable and undesirable effects are still not completely understood. Faced with the unmet clinical need to limit glucocorticoid-induced adverse effects alongside ensuring the preservation of anti-inflammatory actions, several strategies have been pursued. The coprescription of existing licensed drugs to treat incident adverse effects can be effective, but data examining the prevention of adverse effects are limited. Novel selective glucocorticoid receptor agonists and selective glucocorticoid receptor modulators have been designed that aim to specifically and selectively activate anti-inflammatory responses based upon their interaction with the glucocorticoid receptor. Several of these compounds are currently in clinical trials to evaluate their efficacy. More recently, strategies exploiting tissue-specific glucocorticoid metabolism through the isoforms of 11β-hydroxysteroid dehydrogenase has shown early potential, although data from clinical trials are limited. The aim of any treatment is to maximize benefit while minimizing risk, and within this review we define the adverse effect profile associated with glucocorticoid use and evaluate current and developing strategies that aim to limit side effects but preserve desirable therapeutic efficacy.

Trends in diabetic eye disorders and associated comorbidities in Taiwan: a 10-year nationwide population-based cohort study

BACKGROUND/AIMS

In-depth analysis is needed to investigate trends in diabetic retinopathy (DR), diabetic macular oedema (DME) and associated comorbidities in patients with type 2 diabetes mellitus (T2DM) so that we can better understand their prevalence and incidence.

METHODS

A retrospective population-based study was conducted using data from Taiwan's National Health Insurance Research Database from 2005 to 2015, and T2DM, DR and associated comorbidities were identified based on diagnostic codes. We used a standardised incidence rate with age and sex adjustment to estimate the prevalence and incidence of DR, proliferative DR (PDR), advanced PDR (aPDR) and DME, while the difference in each study period was calculated as the annual percentage change. We used the absolute standardised difference to analyse changes in related comorbidities in different periods.

RESULTS

The population of patients with DM increased over 50% between 2005 and 2015, while the prevalence and incidence of DR decreased, as did the incidence of PDR and aPDR. However, the prevalence and incidence of DME increased over the course of 10 years, with an upward trend in all forms of DR. The percentage of patients with hyperlipidaemia in DME and all DR increased, and the percentage of patients with end-stage renal disease (ESRD) was also elevated in DME.

CONCLUSION

The prevalence and incidence of DR, PDR and aPDR decreased with time in patientsT2DM, while the ratio of DME increased gradually. The incidence of hyperlipidaemia also increased in all forms of diabetic eye disorders, while ESRD increased solely in DME.

Review of the Case Reports on Metformin, Sulfonylurea, and Thiazolidinedione Therapies in Type 2 Diabetes Mellitus Patients

Type 2 diabetes mellitus (T2DM) is the world's most common metabolic disease. The development of T2DM is mainly caused by a combination of two factors: the failure of insulin secretion by the pancreatic β-cells and the inability of insulin-sensitive tissues to respond to insulin (insulin resistance); therefore, the disease is indicated by a chronic increase in blood glucose. T2DM patients can be treated with mono- or combined therapy using oral antidiabetic drugs and insulin-replaced agents; however, the medication often leads to various discomforts, such as abdominal pain, diarrhea or constipation, nausea and vomiting, and hypersensitivity reactions. A biguanide drug, metformin, has been used as a first-line drug to reduce blood sugar levels. Sulfonylureas work by blocking the ATP-sensitive potassium channel, directly inducing the release of insulin from pancreatic β-cells and thus decreasing blood glucose concentrations. However, the risk of the failure of sulfonylurea as a monotherapy agent is greater than that of metformin or rosiglitazone (a thiazolidinedione drug). Sulfonylureas are used as the first-line drug of choice for DM patients who cannot tolerate metformin therapy. Other antidiabetic drugs, thiazolidinediones, work by activating the peroxisome proliferator-activated receptor gamma (PPARγ), decreasing the IR level, and increasing the response of β-cells towards the glucose level. However, thiazolidines may increase the risk of cardiovascular disease, weight gain, water retention, and edema. This review article aims to discuss case reports on the use of metformin, sulfonylureas, and thiazolidinediones in DM patients. The literature search was conducted on the PubMed database using the keywords 'metformin OR sulfonylureas OR thiazolidinediones AND case reports', filtered to 'free full text', 'case reports', and '10 years publication date'. In some patients, metformin may affect sleep quality and, in rare cases, leads to the occurrence of lactate acidosis; thus, patients taking this drug should be monitored for their kidney status, plasma pH, and plasma metformin level. Sulfonylureas and TZDs may cause a higher risk of hypoglycemia and weight gain or edema due to fluid retention. TZDs may be associated with risks of cardiovascular events in patients with concomitant T2DM and chronic obstructive pulmonary disease. Therefore, patients taking these drugs should be closely monitored for adverse effects.

Current Treatments for Diabetic Macular Edema

Diabetic retinopathy is a major retinal disorder and a leading cause of blindness. Diabetic macular edema (DME) is an ocular complication in patients with diabetes, and it can impair vision significantly. DME is a disorder of the neurovascular system, and it causes obstructions of the retinal capillaries, damage of the blood vessels, and hyperpermeability due to the expression and action of vascular endothelial growth factor (VEGF). These changes result in hemorrhages and leakages of the serous components of blood that result in failures of the neurovascular units (NVUs). Persistent edema of the retina around the macula causes damage to the neural cells that constitute the NVUs resulting in diabetic neuropathy of the retina and a reduction in vision quality. The macular edema and NVU disorders can be monitored by optical coherence tomography (OCT). Neuronal cell death and axonal degeneration are irreversible, and their development can result in permanent visual loss. Treating the edema before these changes are detected in the OCT images is necessary for neuroprotection and maintenance of good vision. This review describes the effective treatments for the macular edema that are therefore neuroprotective.

The Impact of Systemic Medications on Retinal Function

This study will provide a thorough review of systemic (and select intravitreal) medications, along with illicit drugs that are capable of causing various patterns of retinal toxicity. The diagnosis is established by taking a thorough medication and drug history, and then by pattern recognition of the clinical retinal changes and multimodal imaging features. Examples of all of these types of toxicity will be thoroughly reviewed, including agents that cause retinal pigment epithelial disruption (hydroxychloroquine, thioridazine, pentosan polysulfate sodium, dideoxyinosine), retinal vascular occlusion (quinine, oral contraceptives), cystoid macular edema/retinal edema (nicotinic acid, sulfa-containing medications, taxels, glitazones), crystalline deposition (tamoxifen, canthaxanthin, methoxyflurane), uveitis, miscellaneous, and subjective visual symptoms (digoxin, sildenafil). The impact of newer chemotherapeutics and immunotherapeutics (tyrosine kinase inhibitor, mitogen-activated protein kinase kinase, checkpoint, anaplastic lymphoma kinase, extracellular signal-regulated kinase inhibitors, and others), will also be thoroughly reviewed. The mechanism of action will be explored in detail when known. When applicable, preventive measures will be discussed, and treatment will be reviewed. Illicit drugs (cannabinoids, cocaine, heroin, methamphetamine, alkyl nitrite), will also be reviewed in terms of the potential impact on retinal function.

The effect of insulin on response to intravitreal anti-VEGF injection in diabetic macular edema in type 2 diabetes mellitus

Objectives

To assess whether insulin therapy impacts the effectiveness of anti-vascular endothelial growth factor (anti-VEGF) injection for the treatment of diabetic macular edema (DME) in type 2 diabetes mellitus.

Methods

This was a retrospective multi-center analysis. The best-corrected visual acuity (BCVA) at 12 months, BCVA change, central macular thickness (CMT), CMT change, and cumulative injection number were compared between the insulin and the oral hypoglycemic agent (OHA) groups.

Results

The mean final BCVA and CMT improved in both the insulin (N = 137; p < 0.001; p < 0.001, respectively) and the OHA group (N = 61; p = 0.199; p < 0.001, respectively). The two treatment groups were comparable for final BCVA (p = 0.263), BCVA change (p = 0.184), final CMT (p = 0.741), CMT change (p = 0.458), and the cumulative injections received (p = 0.594). The results were comparable between the two groups when stratified by baseline vision (p > 0.05) and baseline HbA1c (p > 0.05).

Conclusion

Insulin therapy does not alter treatment outcomes for anti-VEGF therapy in DME.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12886-022-02325-x.

Monoclonal antibodies in diabetic retinopathy

INTRODUCTION

Diabetic retinopathy (DR), as one of the main complications of diabetes, is among the leading causes of blindness and visual impairment worldwide.

AREAS COVERED

Current clinical therapies include photocoagulation, vitrectomy, and anti-vascular endothelial growth factor (VEGF) therapies. Bevacizumab and ranibizumab are two monoclonal antibodies (mAbs) inhibiting angiogenesis. Intravitreal ranibizumab and bevacizumab can decrease the rate of blindness and retinal thickness, and improve visual acuity whether as monotherapy or combined with other treatments. They can increase the efficacy of other treatments and decrease their adverse events. Although administered intravitreally, they also might enter the circulation and cause systemic effects. This study is aimed to review our current knowledge about mAbs, bevacizumab and ranibizumab, in DR including superiorities, challenges, and limitations. Meanwhile, we tried to shed light on new ideas to overcome these limitations. Our latest search was done in April 2021 mainly through PubMed and Google Scholar. Relevant clinical studies were imported.

EXPERT OPINION

Future direction includes detection of more therapeutic targets considering other components of DR pathophysiology and shared pathogenesis of DR and neurodegenerative diseases such as Parkinson's disease and Alzheimer's disease, the treat-and-extend regimen, and new ways of drug delivery and other routes of ocular drug administration.

Risk of diabetic macular oedema with sodium-glucose cotransporter-2 inhibitors in type 2 diabetes patients: A multi-institutional cohort study in Taiwan

AIMS

To investigate the risk of diabetic macular oedema (DMO) associated with the use of sodium-glucose cotransporter-2 (SGLT2) inhibitors in patients with type 2 diabetes mellitus (T2DM).

MATERIALS AND METHODS

We conducted a retrospective cohort study by analysing a large multi-institutional electronic medical records database in Taiwan. We included adult patients with T2DM without DMO newly receiving either SGLT2 inhibitors or glucagon-like peptide-1 receptor agonists (GLP-1RAs) during the period 2016 to 2018. We used propensity scores with inverse probability of treatment weighting to generate comparable groups. The study outcome was incident DMO, determined by clinical diagnosis during outpatient visits or admissions. We followed patients from the index date to either DMO occurrence, last clinical visit, patient death, or December 31, 2020. We performed Cox proportional hazards regression models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the risk of DMO.

RESULTS

We included 9986 new users of SGLT2 inhibitors (mean [SD] age 59.6 (12.1) years, median [interquartile range {IQR}] glycated haemoglobin [HbA1c] 70 (61-81)mmol/mol, estimated glomerular filtration rate [eGFR] 89.1 [71.4-108.7] mL/min/1.73 m² and urine albumin-creatinine ratio [UACR] 26.1 [9.7-117.6] mg/g) and 1067 new users of GLP-1RAs (mean [SD] age 58.4 (41.5) years, median [IQR] HbA1c 73 [64-84] mmol/mol, eGFR 91.6 [68.6-114.0] mL/min/1.73 m² and UACR 37.6 [11.1-153.2] mg/g) with similar baseline characteristics. Lower DMO risks were observed among patients newly receiving SGLT2 inhibitors (7.9/1000 person-years), compared to those receiving GLP-1RAs (10.7/1000 person-years) with an HR of 0.75 (95% CI 0.64-0.88).

CONCLUSIONS

Our findings suggest use of SGLT2 inhibitors was associated with lower risk of DMO in T2DM patients in clinical practice, compared to use of GLP-1RAs. Future studies are necessary to confirm this observation.

The ocular adverse effects of oral drugs

Some commonly prescribed drugs have ocular adverse effects. Many parts of the eye can be affected by oral drugs. Some ocular adverse effects may be reversed with medical or surgical intervention whereas other drugs may cause irreversible loss of vision

The risk of visual loss can be reduced by a number of approaches, including monitoring for ocular toxicity, reducing the drug dose, or stopping the drug and looking for an alternative. This can be supported by good communication between the prescribing clinician and ophthalmologist

Infrequent or delayed ocular adverse effects may not be identified in clinical trials of new drugs. Reporting adverse events is therefore important

Diabetic and Retinal Vascular Eye Disease

The retinal vasculature is the only neurovascular system directly visible to the human eye, easily evaluated by fundoscopy and many imaging modalities. This window allows physicians to diagnose and treat retinal pathologies and detect systemic diseases including diabetes, hypertension, hypercoagulable/hyperviscosity syndromes, and vasculitis. Diabetic retinopathy is the most common retinal vascular disease, followed by retinal vein and artery occlusion. Patients with these conditions require medical optimization to prevent further damage to the eyes and to the other organs. Both the internists and medical subspecialists play a crucial role in the prevention, detection, evaluation, and management of vision-threatening retinal vascular diseases.

Safety and Efficacy of Ranibizumab and Luseogliflozin Combination Therapy in Patients with Diabetic Macular Edema: Protocol for a Multicenter, Open-Label Randomized Controlled Trial

INTRODUCTION

Diabetic macular edema (DME) threatens daily life activities such as reading and driving and reduces the patients' quality-of-life. Recently, anti-vascular endothelial growth factor (VEGF) agents have become a first-line therapy in DME. However, therapy with anti-VEGF agents has several problems: repeated invasive injections are required; medical costs are high; and a certain proportion of patients with DME are resistant to treatment with anti-VEGF agents. While sodium-glucose co-transporter 2 (SGLT2) inhibitors have been widely used for the treatment of type 2 diabetes mellitus (T2DM), the effects of a combination therapy with anti-VEGF agent and SGLT2 inhibitor on DME are not yet known.

METHODS

This study enrolls subjects with T2DM and DME, randomizes them into either a study agent treatment group (treated with ranibizumab as anti-VEGF agent and luseogliflozin as SGLT2 inhibitor) or a control group (treated with ranibizumab and glimepiride), and observes the subjects for 52 weeks after initiation of treatment. Planned outcomes: The primary endpoint is intergroup difference in the number of intravitreal anti-VEGF injections to the study eye from baseline to week 48. Secondary and exploratory endpoints include safety and ophthalmologic and internal medical clinical parameters.

REGISTRATION

This study is registered at the University Hospital Medical Information Network Clinical Trial Registry (UMIN000033961) and Japan Registry of Clinical Trials (jRCTs031180210).

Diabetic Macular Edema: State of Art and Intraocular Pharmacological Approaches

Diabetic macular edema (DME) is the main cause of vision loss in diabetic retinopathy (DR). Although it is one of the main complications of diabetes, the pathogenesis of DME is not completely understood. The hyperglycemic state promotes the activation of multiple interlinked pathways leading to DME. Different classifications have been proposed: based on clinical features, on pathogenesis or on diagnostic tests (optical coherence tomography - OCT and fluorescin angiography - FA). The multimodal imaging allows a better analysis of the morphological features of the DME. Indeed, new inflammatory biomarkers have been identified on OCT. Also, several studies are evaluating the role of the morphological features, identified on multimodal imaging, to find new prognostic factors. Over the past decade, great progresses have been made in the management of DME. Therapeutic alternatives include intraocular injection of anti-vascular endothelial grow factor agents (anti-VEGF) and steroid molecules, focal/grid laser photocoagulation and vitreo-retinal surgery. This review is focused on the description and analysis of the current intravitreal therapeutic pharmacological strategies. Current guidelines recommend anti-VEGF as first line therapy in DME. Corticosteroids are becoming increasingly relevant blocking the inflammatory cascade and indirectly reducing VEGF synthesis.

Natural history of diabetic macular edema and factors predicting outcomes in sham-treated patients (MEAD study)

PURPOSE

To describe the natural history of diabetic macular edema (DME) with respect to best-corrected visual acuity (BCVA) and central retinal thickness (CRT) outcomes and to identify baseline patient characteristics and systemic factors associated with improvement or worsening of outcomes in sham-treated patients.

METHODS

The study population was sham-treated patients (n = 350) in the 3-year MEAD registration study of dexamethasone intravitreal implant for treatment of DME. Patients had center-involved DME and received sham intravitreal injections in the study eye at ≥ 6-month intervals. Potential prognostic factors for outcomes were evaluated using multiple linear regression analysis.

RESULTS

Visual and anatomic outcomes were poorer in patients who left the study early (n = 198) than in study completers (n = 152). Mean change in BCVA from baseline at the last visit with available data was + 0.9 letters; 37.5% of patients had no change in BCVA, 23.2% had gained > 10 letters, and 16.0% had lost > 10 letters. Older age and baseline diabetic retinopathy score > 6 were associated with worse BCVA outcomes; thicker baseline CRT and larger number of hypertension medications used were associated with larger reductions in CRT during the study.

CONCLUSIONS

BCVA and CRT outcomes were variable in this population of DME patients with generally good glycemic control. In DME patients without active treatment, older age and baseline diabetic retinopathy score > 6 were associated with less improvement in BCVA; thicker baseline CRT and a larger number of antihypertensive medications used predicted better improvement in CRT.

TRIAL REGISTRATION

The MEAD study trials are registered at ClinicalTrials.gov with the identifiers NCT00168337 and NCT00168389.

Rapidly reversing bilateral macular edema associated with fluid overload in a young type 1 diabetic

We report a case of sudden onset bilateral diminution of vision in a young lady with type 1 diabetes. She was administered intravenous fluids for correction of diabetic ketoacidosis (DKA) prior to onset of her ocular symptoms. Dramatic resolution of macular edema was noted within a very short period after correction of fluid input–output ratio. Visual acuity was restored to baseline after 3 days without any active ocular intervention.

New anti-hyperglycaemic agents for type 2 diabetes and their effects on diabetic retinopathy

There has been an increase in the range of non-insulin anti-hyperglycaemic agents used to treat type 2 diabetes. With the globally rising rates of type 2 diabetes and complications such as diabetic retinopathy, it is important for ophthalmologists to be aware of these new agents and their impacts on diabetic retinopathy and diabetic macular oedema. We conducted a review of the literature to determine if there were any beneficial or harmful effects of the currently used anti-hyperglycaemic agents on diabetic retinopathy or diabetic macular oedema. Our review of the current literature found that apart from thiazolidinediones, anti-hyperglycaemic agents have been reported to have beneficial or neutral effects on diabetic eye complications. Thiazolidinediones (pioglitazone is the only one currently available) have been linked to incident or worsening diabetic macular oedema, although the rate is believed to be low. Glucagon-like peptide 1 (GLP1) agonists (incretins) in general are beneficial except semaglutide which is associated with increased rates of diabetic retinopathy complications. These results have implications for selection of anti-hyperglycaemic agents for patients with diabetic retinopathy or macular oedema. Further studies need to be conducted to identify if reported beneficial effects are independent of the impact of glycaemic control. Early worsening of retinopathy with tight glycaemic control should also be noted in interpretation of future studies.

Update of inflammatory proliferative retinopathy: Ischemia, hypoxia and angiogenesis

Diabetic retinopathy (DR) and retinopathy of prematurity (ROP) present two examples of proliferative retinopathy, characterized by the same stages of progression; ischemia of the retinal vessels, leads to hypoxia and to correct the problem there is the setting up of uncontrolled angiogenesis, which subsequently causes blindness or even detachment of the retina. The difference is the following; that DR initiated by the metabolic complications that are due to hyperglycemia, and ROP is induced by overexposure of the neonatal retina to oxygen. In this review, we will demonstrate the physiopathological mechanism of the two forms of proliferative retinopathy DR and ROP, in particular the role of the CD40/CD40L axis and IL-1 on vascular complications and onset of inflammation of the retina, the implications of their effects on the onset of pathogenic angiogenesis, thus understanding the link between platelets and retinal ischemia. In addition, what are the therapeutic targets that could slow its progression?

Management of hyperglycaemia and steroid (glucocorticoid) therapy: a guideline from the Joint British Diabetes Societies (JBDS) for Inpatient Care group

Glucocorticoids (steroids) are widely used across many medical specialities for their anti-inflammatory and immunosuppressive properties. However, one of their major side effects is the development of hyperglycaemia. It is well recognized that high glucose levels in people with diabetes in hospital are associated with harm and increased lengths of hospital stay. The use of glucocorticoid (steroid) treatment in people with pre-existing diabetes will undoubtedly result in worsening glucose control, and this may be termed 'steroid-induced hyperglycaemia', and will warrant temporary additional, and more active, glycaemic management. A rise in glucose may occur in people without a known diagnosis of diabetes, and this may be termed 'steroid-induced diabetes'. There is a lack of evidence to guide how people with hyperglycaemia should be managed, and much of the guidance given here is a consensus based on best practice collated from around the United Kingdom. Where evidence is available, this is referenced. These guidelines on the management of people with diabetes treated with steroids has been adapted specifically for Diabetic Medicine. The full version of the guidelines can be found on line at: www.diabetes.org.uk/joint-british-diabetes-society or https://abcd.care/joint-british-diabetes-societies-jbds-inpatient-care-group.

Efficiency of fenofibrate in facilitating the reduction of central macular thickness in diabetic macular edema

PURPOSE

The purpose of this study is to study the benefit of addition of oral fenofibrate to the current regimen of diabetic macular edema (DME) management and quantify its effect on macular thickness and visual function in DME.

METHODS

Fifty-three eyes of 50 patients were randomized into treatment (Group A) (oral fenofibrate 160 mg/day) and control groups (Group B). Both groups underwent treatment of DME as per the standard treatment protocol of our hospital including intravitreal injections (anti-vascular endothelial growth factor/steroid) and grid laser. Patients were followed up every 2 months to note the visual acuity and central macular thickness (CMT) for 6 months.

RESULTS

Our groups were matched with respect to age (P = 0.802), mean diabetic age (P = 0.878), serum HbA1C levels (P = 0.523), and serum triglyceride levels (P = 0.793). The mean reduction in CMT was 136 μ in Group A and 83 μ in Group B at the end of 6 months. This difference was statistically significant (P = 0.031). Visual acuity improvement was 0.15 in Group A and 0.11 in Group B at the end of 6 months (P = 0.186). On subgroup analysis in Group A, we found that there was no difference in reduction of CMT between hypertensives and normotensives (P = 0.916), in patients with normal triglyceride levels and increased triglyceride levels (P = 0.975).

CONCLUSION

Addition of fenofibrate to the standard protocol of DME management seems to facilitate reduction of CMT and probably have an added benefit on the visual functions.

Diabetic macular edema-like ocular lesions in male spontaneously diabetic torii fatty rats

Diabetic macular edema (DME) is a major factor contributing to visual disabilities in diabetic patients, and the number of patients is increasing. Animal models play a key role in the development of novel therapies. In this study, pathophysiological analyses of ocular lesions in Spontaneously Diabetic Torii (SDT) fatty rats were performed. First, vascular endothelial growth factor (VEGF) concentrations in vitreous humor, retinal vascular permeability and retinal thickness were measured in SDT fatty rats (Experiment 1). Furthermore, the pharmacological effects of two anti-diabetic drugs, phlorizin and pioglitazone, on retinal lesions were evaluated (Experiment 2). As results, the SDT fatty rats exhibited VEGF increase in vitreous humor at 8 and 16 weeks of age, and both retinal vascular hyperpermeability and retinal thickening at 16 weeks of age. In particular, the layers between the retinal internal limiting membrane and the outer nuclear layer were thickened. Phlorizin treatment from 4 to 16 weeks of age improved hyperglycemia and normalized retinal thickness; however, the effect of pioglitazone on retinal thickness was not strong despite the normalization of hyperglycemia. These data demonstrate that the male SDT fatty rat is a useful model for developing new therapeutic approaches in DME.

Lack of Longitudinal Association Between Thiazolidinediones and Incidence and Progression of Diabetic Eye Disease: The ACCORD Eye Study

PURPOSE

To report the longitudinal association between use of thiazolidinediones (TZDs), visual acuity (VA) change, and diabetic eye disease incidence and progression.

DESIGN

Cohort study ancillary to a randomized clinical trial.

METHODS

We analyzed baseline and 4-year follow-up data of 2856 ACCORD trial participants with no history of proliferative diabetic retinopathy. Based on stereoscopic fundus photographs, we evaluated diabetic macular edema (DME) progression and DR progression. We also evaluated 10- and 15-letter change on the ETDRS visual acuity chart. Main outcome measures were incidence or progression of DME or DR and change in visual acuity.

RESULTS

TZD use was not associated with DME incidence in either the analysis of any use (adjusted odds ratio [aOR] [95% CI]: 1.22 [0.72-2.05]) or duration of use (aOR: 1.02 [0.99-1.04]). Diabetic retinopathy (DR) incidence/progression was more common in patients with no or mild DR at baseline who were ever treated with TZDs (aOR: 1.68 [1.11-2.55]), but this association disappeared when adjusting for the time on TZD (aOR: 1.02 [1.00-1.04]). DR progression among those with moderate or worse DR at baseline was no different between TZD users and non-users. TZD usage had no effect on the ultimate visual acuity outcome.

CONCLUSION

In this longitudinal study of patients with type 2 diabetes, we found no association between TZD use and visual acuity outcomes or DME progression, and no consistent evidence of increased DR progression in patients ever treated with TZDs vs those never treated with TZDs.

Uveoretinal Adverse Effects Presented during Systemic Anticancer Chemotherapy: a 10-Year Single Center Experience

BACKGROUND

The present study describes our 10-year experience with uveoretinal adverse events that manifest because of chemotherapy.

METHODS

A retrospective chart review was performed for all patients who presented to the ophthalmologic department while undergoing systemic chemotherapy between July 2005 and June 2015.

RESULTS

A total of 55 patients (mean age, 51.2 years, 38 women [69.1%]) suspected of having uveoretinal disease owing to the use of chemotherapeutic agents alone were enrolled. Breast cancer was the predominant disease (36.4%); noninfectious anterior uveitis (21.8%) was the most common condition. Bilateral involvement was observed in 16 patients (29.1%). Although cisplatin (21.8%) was the most commonly used drug, daunorubicin, cytarabine, tamoxifen, toremifene, and imatinib were also frequently used. The median duration until ophthalmologic diagnosis was 208.5 days (range, 19-5,945 days). The proportion of patients with final visual acuity (VA) < 20/40 Snellen VA (0.5 decimal VA) was 32.7%. However, no relationship was observed between final VA < 20/40 and age, sex, therapeutic agents, and metastasis.

CONCLUSION

Uveoretinal complications were mostly mild to moderate and exhibited a favorable response to conservative therapy. A considerable number of patients exhibited significant irreversible loss of vision after cessation of the causative chemotherapeutic agent. Ophthalmological monitoring is required during chemotherapy.

Does tight control of systemic factors help in the management of diabetic retinopathy?

Diabetic retinopathy (DR), one of the leading causes of preventable blindness, is associated with many systemic factors that contribute to the development and progression of this microvascular complication of diabetes. While the duration of diabetes is the major risk factor for the development of DR, the main modifiable systemic risk factors for development and progression of DR are hyperglycemia, hypertension, and dyslipidemia. This review article looks at the evidence that control of these systemic factors has significant benefits in delaying the onset and progression of DR.

Optimizing Medical Management in Patients with Sight-Threatening Diabetic Retinopathy

INTRODUCTION

Diabetic retinopathy is a leading cause of blindness in adults of working age. Patients with sight-threatening diabetic retinopathy (STDR) often have poor control of modifiable risk factors, including blood pressure and blood glucose. Patients in our eye department with STDR whose diabetes was managed only by their general practitioner (GP) were referred to a diabetes specialist. We have reviewed these referrals and assessed the control of modifiable risk factors in these patients at the time of referral.

METHODS

A retrospective study was performed which identified 54 patients with STDR who had been referred from our eye department to a diabetes specialist between May 2013 and August 2014. Patient demographics, grades of retinopathy, glycated hemoglobin (HbA1c) levels, blood pressure, and lipid profiles were noted from the initial clinic visit and the first clinic appointment after 12 months. Initial management and any subsequent changes to management were recorded.

RESULTS

Of the 54 patients initially referred to the dedicated diabetic retinopathy clinic, data from 32 patients were available for analysis; 22 patients failed to attend the clinic. The majority of patients who presented to the clinic were found to have inadequate control of modifiable risk factors. At the initial clinic visit, nine of the 32 (28%) patients had a blood pressure that was less than the target of 130/80 mmHg and only two (6%) had a HbA1c level of less than the target of 48 mmol/L for type 2 diabetes and 58 mmol/L for type 1 diabetes, respectively. Changes were made to the management in 24 (75%) of the patients. Blood pressure management was changed in 18 (56%) patients. Overall, changes were made to blood pressure management and lipid and glycemic medication, including insulin.

CONCLUSION

The majority of patients with STDR were receiving suboptimal medical management. Collaboration between GPs, diabetes specialists, and ophthalmologists can lead to optimized medical management. All eye departments should develop protocols specifying when patients with diabetic retinopathy should be referred for to a diabetes specialist for input.

Giant retinal pigment epithelial tear associated with fluid overload due to end-stage diabetic kidney disease

Purpose

To report a case of a giant retinal pigment epithelial (RPE) tear associated with fluid overload in a patient with diabetic macular edema (DME) and kidney disease.

Observations

A 60-year-old man with type 2 diabetes mellitus and end-stage diabetic kidney disease who had gained weight because of fluid overload complained of a visual disturbance in the left eye that had started a few days earlier. The left fundus showed a RPE defect in two temporal quadrants under an extensive serous retinal detachment (SRD) with exacerbation of the original DME. Seven days later, he was admitted for severe edema and pleural effusion. No overt signs of congestive heart failure were noted. On admission, the RPE defect had markedly widened to involve the macula. Spectral-domain optical coherence tomography images showed substantial intraretinal fluid and an extensive SRD with rolled edges of the retinal pigment epithelium, which led to the diagnosis of a RPE tear. The fluid under the SRD was absorbed on the fourth hospital day and the substantial intraretinal fluid resolved on the eleventh day after systemic management of fluid overload only without ophthalmic treatment. The change in the appearance of the RPE area was minimal and the visual field defect remained even after 6 months.

Conclusions and importance

A RPE tear may develop in association with fluid overload in patients with diabetes.

The Role of Systemic Risk Factors in Diabetic Retinopathy

Diabetic retinopathy is an increasingly common medical issue in the United States. The risk of developing the disease or having the disease progress is caused by many systemic health factors. This article examines the existing literature on the links between glycemic control, arterial hypertension, high cholesterol and hyperlipidemia, obesity, inflammatory markers, sleep-disordered breathing, and exercise with risk of diabetic retinopathy development and prevention. The literature shows benefit for good glycemic and blood pressure control. The effects of cholesterol, and lipid control, inflammatory markers, sleep-disordered breathing, obesity, and exercise are less well established.

Diabetic Macular Edema: Pathophysiology and Novel Therapeutic Targets

Diabetic macular edema (DME) is the major cause of vision loss in diabetic persons. Alteration of the blood-retinal barrier is the hallmark of this disease, characterized by pericyte loss and endothelial cell-cell junction breakdown. Recent animal and clinical studies strongly indicate that DME is an inflammatory disease. Multiple cytokines and chemokines are involved in the pathogenesis of DME, with multiple cellular involvement affecting the neurovascular unit. With the introduction of anti-vascular endothelial growth factor (VEGF) agents, the treatment of DME has been revolutionized, and the indication for laser therapy has been limited. However, the response to anti-VEGF drugs in DME is not as robust as in proliferative diabetic retinopathy, and many patients with DME do not show complete resolution of fluid despite multiple intravitreal injections. Potential novel therapies targeting molecules other than VEGF and using new drug-delivery systems currently are being developed and evaluated in clinical trials.

Current intravitreal pharmacologic therapies for diabetic macular edema

INTRODUCTION

Diabetic retinopathy is the leading cause of vision loss in working-age adults; it is a highly prevalent cause of vision loss overall and has a potent impact on the quality of life in those with diabetes mellitus and public health in general. Diabetic macular edema (DME) is the most common cause of vision loss from diabetic retinopathy. In patients with diabetes mellitus, chronic hyperglycemia leads to activation of the inflammatory cascade and retinal capillary damage that result in microaneurysm formation in the retina. In addition to the possibility of associated ischemia, microaneurysms are hyperpermeable; the resultant loss of the blood-retinal barrier leads to vision loss if consequent edema involves the center of the fovea. The standard of DME therapy for >25 years was focal laser photocoagulation applied to or near the microaneurysms. However, results from clinical trials of intravitreal vascular endothelial growth factor (VEGF) blockers and corticosteroids for the treatment of DME have led to a dramatic paradigm shift away from laser therapy to primary treatment with these pharmacologic agents.

METHODS

Medline literature search of approaches for treating DME.

RESULTS

Intravitreal pharmacologic treatments with anti-VEGF agents and corticosteroids have recently been shown to be superior to laser treatment of DME.

CONCLUSION

The existence of pharmacologic treatment of DME, shown to be superior to laser monotherapy, has created a seismic change in the approach of treatment of these patients. This review provides a summary of the therapies and the rationale regarding the current pharmacologic therapy of DME.

Updates in the management of diabetic macular edema

Diabetes mellitus is a chronic disease which has multiple effects on different end-organs, including the retina. In this paper, we discuss updates on diabetic macular edema (DME) and the management options. The underlying pathology of DME is the leakage of exudates from retinal microaneurysms, which trigger subsequent inflammatory reactions. Both clinical and imaging techniques are useful in diagnosing, classifying, and gauging the severity of DME. We performed a comprehensive literature search using the keywords "diabetes," "macula edema," "epidemiology," "pathogenesis," "optical coherence tomography," "intravitreal injections," "systemic treatment," "hypertension," "hyperlipidemia," "anemia," and "renal disease" and collated a total of 47 relevant articles published in English language. The main modalities of treatment currently in use comprise laser photocoagulation, intravitreal pharmacological and selected systemic pharmacological options. In addition, we mention some novel therapies that show promise in treating DME. We also review systemic factors associated with exacerbation or improvement in DME.

Optical coherence tomography imaging of macular oedema

Macular oedema (ME) occurs in a wide variety of pathological conditions and accounts for different degrees of vision loss. Early detection of ME is therefore critical for diagnosis and therapeutic management. Optical coherence tomography (OCT) is a non-contact, diagnostic method that uses infrared light, which allows the analysis of the retinal structure by means of high-resolution tomographic cross sections. The identification, localisation, quantification and long-term follow-up of fluid collections are the most important capabilities of OCT. Since the introduction of OCT in clinical practice, it has become an invaluable diagnostic tool and different patterns of ME have been reported. The purpose of this manuscript is to review OCT profiles of ME according to the aetiology and describe what has been reported regarding intraretinal features in vivo.

Do thiazolidinediones still have a role in treatment of type 2 diabetes mellitus?

Thiazolidinediones have been introduced in the treatment of type 2 diabetes mellitus (T2DM) since the late 1990s. Although troglitazone was withdrawn from the market a few years later due to liver toxicity, both rosiglitazone and pioglitazone gained widespread use for T2DM treatment. In 2010, however, due to increased risk of cardiovascular events associated with its use, the European Medicines Agency recommended suspension of rosiglitazone use and the Food and Drug Administration severely restricted its use. Thus pioglitazone is the only thiazolidinedione still significantly employed for treating T2DM and it is the only molecule of this class still listed in the American Diabetes Association-European Association for the Study of Diabetes 2012 Position Statement. However, as for the other thiazolidinediones, use of pioglitazone is itself limited by several side effects, some of them potentially dangerous. This, together with the development of novel therapeutic strategies approved in the last couple of years, has made it questionable whether or not thiazolidinediones (namely pioglitazone) should still be used in the treatment of T2DM. This article will attempt to formulate an answer to this question by critically reviewing the available data on the numerous advantages and the potentially worrying shortcomings of pioglitazone treatment in T2DM.

Current status in diabetic macular edema treatments

Diabetes is a serious chronic condition, which increase the risk of cardiovascular diseases, kidney failure and nerve damage leading to amputation. Furthermore the ocular complications include diabetic macular edema, is the leading cause of blindness among adults in the industrialized countries. Today, blindness from diabetic macular edema is largely preventable with timely detection and appropriate interventional therapy. The treatment should include an optimized control of glycemia, arterial tension, lipids and renal status. The photocoagulation laser is currently restricted to focal macular edema in some countries, but due the high cost of intravitreal drugs, the use of laser treatment for focal and diffuse diabetic macular edema (DME), can be valid as gold standard in many countries. The intravitreal anti vascular endothelial growth factor drugs (ranibizumab and bevacizumab), are indicated in the treatment of all types of DME, but the correct protocol for administration should be defined for the different Retina Scientific Societies. The corticosteroids for diffuse DME, has a place in pseudophakic patients, but its complications restricted the use of these drugs for some patients. Finally the intravitreal interface plays an important role and its exploration is mandatory in all DME patients.

Risk factors associated with diabetic macular edema

Diabetic macular edema (DME) is the most common cause of vision loss in patients with type 1 and type 2 diabetes. Glycemic control, hypertension, and dyslipidemia are known to be important risks factors for DME. In addition, nephropathy, anemia, sleep apnea, glitazone usage, and pregnancy are also important modifiable risk factors. It is important for physicians of different subspecialties to work together and understand multiple aspects of DME and diabetic healthcare.

Molecular Implications of the PPARs in the Diabetic Eye

Diabetic retinopathy (DR) remains as the leading cause of blindness among working age individuals in developed countries. Current treatments for DR (laser photocoagulation, intravitreal corticosteroids, intravitreal anti-VEGF agents, and vitreoretinal surgery) are applicable only at advanced stages of the disease and are associated with significant adverse effects. Therefore, new pharmacological treatments for the early stages of the disease are needed. Emerging evidence indicates that peroxisome proliferator-activator receptors (PPARs) agonists (in particular PPARα) are useful for the treatment of DR. However, the underlying molecular mechanisms are far from being elucidated. This paper mainly focuses on PPARs expression in the diabetic eye, its molecular implications, and the effect of PPAR agonists as a new approach for the treatment of DR. The availability of this new strategy will not only be beneficial in treating DR but may also result in a shift towards treating earlier stages of diabetic retinopathy, thus easing the burden of this devastating disease (Cheung et al. (2010)).

Thiazolidinedione safety

INTRODUCTION

Thiazolidinediones (TZDs) initially showed great promise as unique receptor-mediated oral therapy for type 2 diabetes, but a host of serious side effects, primarily cardiovascular, have limited their utility. It is crucial at this point to perform a risk-benefit analysis to determine what role TZDs should play in our current treatment of type 2 diabetes and where the future of this class of drugs is headed.

AREAS COVERED

This review provides a comprehensive overview of the literature from 2000 onward reporting the known side effects of rosiglitazone and pioglitazone, with commentary on the quality of the data available, putative mechanism of each side effect and clinical significance. Finally, a perspective on the future of the TZDs as a class is provided.

EXPERT OPINION

The current TZDs are first-generation, non-specific activators of peroxisome proliferator-activated receptor (PPAR) gamma, resulting in a wide array of deleterious side effects that currently limit their use. However, the development of highly targeted selective PPAR gamma modulators (SPPARγMs) and dual PPAR gamma/alpha agonists is on the horizon.