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

Diabetes Mellitus and Neurovascular Pathology: A Comprehensive Review of Retinal and Brain Lesions

Diabetes mellitus (DM) is a chronic metabolic disorder marked by persistent hyperglycemia, which significantly impacts vascular health. This review comprehensively analyzes the neurovascular complications associated with DM, focusing on retinal and brain lesions. Diabetes is categorized into type 1 DM, type 2 DM, and gestational DM, each presenting unique challenges and risks. The condition accelerates vascular damage through mechanisms such as endothelial dysfunction, inflammation, and oxidative stress, leading to severe microvascular complications. Diabetic retinopathy is a primary concern, with its progression from non-proliferative to proliferative stages potentially resulting in vision loss. Concurrently, diabetes contributes to neurovascular damage in the brain, increasing the risk of cognitive decline and cerebrovascular events. This review examines the pathophysiological mechanisms underlying these complications, evaluates current diagnostic and management strategies, and highlights recent advancements in imaging technologies and therapeutic approaches. Integrating these insights is crucial for improving early detection, treatment, and management of diabetes-related neurovascular issues. Future research should focus on innovative preventive measures and therapeutic interventions to mitigate the long-term impact of diabetes on vascular health. By enhancing our understanding of these complex interactions, this review aims to contribute to better clinical practices and improved patient outcomes in diabetes care.

Nrf-2-dependent antioxidant and anti-inflammatory effects underlie the protective effect of esculeoside A against retinal damage in streptozotocin-induced diabetic rats

Esculeoside A (ESA) is a tomato-derived glycoside with antioxidant and anti-inflammatory properties. The protective effect of ESA against diabetic retinopathy is not well-investigated and was the core objective of this study. In addition, we tested if such protection involves the activation of Nrf2 signaling. Type 1 diabetes mellitus (T1DM) was induced in adult Wistar male rats by an intraperitoneal injection of streptozotocin (65 mg/kg). Non-diabetic and T1DM rats were divided into two subgroup groups given either the vehicle or ESA (100 mg)/kg. An additional T1DM group was given ESA (100 mg/kg) and an Nrf2 inhibitor (2 mg/kg) (n=8 rats/group). Treatments continued for 12 weeks. In this study, according to the histological features, ESA improved the structure of ganglionic cells and increased the number of cells of the inner nuclear and plexiform layers in the retinas of T1DM rats. Concomitantly, it reduced the retina levels of malondialdehyde (lipid peroxides), vascular endothelial growth factor, interleukin-6, tumor necrosis factor-α, Bax, and caspase-3. In the retinas of the control and diabetic rats, ESA boosted the levels of total glutathione, superoxide dismutase, heme-oxygenase-1, and Bcl2, reduced the mRNA levels of REDD1, and enhanced cytoplasmic and nuclear levels of Nrf2. However, ESA failed to alter the mRNA levels of Nrf2 and keap1, protein levels of keap1, plasma glucose, plasma insulin, serum triglycerides, cholesterol, and LDL-c in both the control and T1DM rats. In conclusion, ESA alleviates retinopathy in T1DM rats by suppressing REDD1-associated degradation and inhibiting the Nrf2/antioxidant axis.

Diabetic retinopathy screening guidelines in India: All India Ophthalmological Society diabetic retinopathy task force and Vitreoretinal Society of India Consensus Statement

Diabetic retinopathy (DR) is an emerging preventable cause of blindness in India. All India Ophthalmology Society (AIOS) and Vitreo-Retinal Society of India (VRSI) have initiated several measures to improve of DR screening in India. This article is a consensus statement of the AIOS DR task force and VRSI on practical guidelines of DR screening in India. Although there are regional variations in the prevalence of diabetes in India at present, all the States in India should screen their population for diabetes and its complications. The purpose of DR screening is to identify people with sight-threatening DR (STDR) so that they are treated promptly to prevent blindness. This statement provides strategies for the identification of people with diabetes for DR screening, recommends screening intervals in people with diabetes with and without DR, and describes screening models that are feasible in India. The logistics of DR screening emphasizes the need for dynamic referral pathways with feedback mechanisms. It provides the clinical standards required for DR screening and treatment of STDR and addresses the governance and quality assurance (QA) standards for DR screening in Indian settings. Other aspects incorporate education and training, recommendations on Information technology (IT) infrastructure, potential use of artificial intelligence for grading, data capture, and requirements for maintenance of a DR registry. Finally, the recommendations include public awareness and the need to work with diabetologists to control the risk factors so as to have a long-term impact on prevention of diabetes blindness in India.

Spectrum of eye disorders in diabetes (SPEED) in India. Report # 2. Diabetic retinopathy and risk factors for sight threatening diabetic retinopathy in people with type 2 diabetes in India

Purpose:

To assess the proportion of people with type 2 diabetes mellitus (T2DM) with diabetic retinopathy (DR) and sight-threatening DR (STDR) and associated risk factors in select eye-care facilities across India.

Methods:

In this observational study, data of people with T2DM presenting for the first time at the retina clinic of eye-care facilities across India was recorded. Data collected in 2016 over 6 months included information on systemic, clinical, and ocular parameters. International Clinical Diabetic Retinopathy (ICDR) classification scale was used to grade DR. STDR was defined as presence of severe nonproliferative (NPDR), proliferative diabetic retinopathy (PDR), and/or diabetic macular edema (DME).

Results:

The analysis included 11,182 people with T2DM from 14 eye-care facilities (mean age 58.2 ± 10.6 years; mean duration of diabetes 9.1 ± 7.6 years; 59.2% male). The age-standardized proportion of DR was 32.3% (95%Confidence Interval, CI: 31.4-33.2) and STDR was 19.1% (95%CI: 18.4-19.8). DME was diagnosed in 9.1% (95%CI: 8.5-9.6) and 10.7% (95%CI: 10.1-11.3) people had PDR. Statistically significant factors associated with increased risk of DR (by multivariate logistic regression analysis) were: male gender (Odds ratio[OR] 1.57, 95%CI: 1.16-2.15); poor glycemic control–glycated hemoglobin (HbA1c >10%)(OR 2.39, 95% CI: 1.1-5.22); requirement of insulin (OR 2.55, 95%CI: 1.8-3.6);history of hypertension (OR 1.42, 95%CI: 1.06-1.88) and duration of diabetes >15 years (OR 5.25, 95%CI: 3.01-9.15).

Conclusion:

Diabetic retinopathy was prevalent in 1/3^rd and sight-threatening DR in 1/5^th of people with T2DM presenting at eye-care facilities in this pan-India facility-based study. The duration of diabetes was the strongest predictor for retinopathy.

Effect of glycemic control and dyslipidemia on plasma vascular endothelial growth factor and pigment epithelium-derived factor in diabetic retinopathy patients in Northern Nigeria

OBJECTIVES

The disruption of the reciprocal regulation between vascular endothelial growth factor (VEGF) and pigment epithelium-derived factor (PEDF) has been associated with the pathogenesis of diabetic retinopathy (DR). This study assessed the levels of VEGF, PEDF, indices of glycemia, and lipid profile in diabetic patients with retinopathy.

METHODS

One hundred fifty participants comprised 50 type 2 diabetic patients with DR, 50 without DR and 50 non-diabetic normotensive controls, aged 30-80 years, were randomly recruited for this case-control study. The study was carried out from November 2017 to December 2018. VEGF, PEDF, glycated hemoglobin (HbA1c), fasting plasma glucose, and lipid profile were determined using standard methods. Blood pressures (BP) and anthropometric indices were measured. Chi-squared test of independence, analysis of variance, and Pearson's correlation were used to analyze data. Statistical significance was set at P < 0.05 and 95% confidence interval.

RESULTS

Both diabetic groups had significantly higher (P = 0.001) systolic and diastolic BP, VEGF, PEDF, HbA1c, fasting plasma glucose, triglycerides, total, high-density lipoprotein-cholesterol (HDL-C), and low-density lipoprotein-cholesterol (LDL-C) levels and significantly lower (P = 0.005) VEGF/PEDF than the controls. However, the diabetics with retinopathy had significantly higher (P = 0.001) HDL-C, LDL-C, VEGF, and PEDF levels compared to the diabetics without retinopathy. There were no significant differences (P > 0.05) in the levels of VEGF, PEDF, and VEGF/PEDF in both groups of diabetics that had good glycemic control and poor glycemic control. There was also no significant difference (P > 0.05) in the levels of VEGF and PEDF between the dyslipidemic and non-dyslipidemic subjects in both diabetic groups.

CONCLUSION

DR is associated with higher levels of VEGF and PEDF while good glycemic control and dyslipidemia seem not to have a profound effect on VEGF and PEDF levels in diabetics with or without DR. Higher PEDF levels are associated with higher atherogenic risk in the diabetics with retinopathy.

The Use of Mobile Personal Health Records for Hemoglobin A1c Regulation in Patients With Diabetes: Retrospective Observational Study

BACKGROUND

The effectiveness of personal health records (PHRs) in diabetes management has already been verified in several clinical trials; however, evidence of their effectiveness in real-world scenarios is also necessary. To provide solid real-world evidence, an analysis that is more accurate than the analyses solely based on patient-generated health data should be conducted.

OBJECTIVE

This study aimed to conduct a more accurate analysis of the effectiveness of using PHRs within electronic medical records (EMRs). The results of this study will provide precise real-world evidence of PHRs as a feasible diabetes management tool.

METHODS

We collected log data of the sugar function in the My Chart in My Hand version 2.0 (MCMH 2.0) app from Asan Medical Center (AMC), Seoul, Republic of Korea, between December 2015 and April 2018. The EMR data of MCMH 2.0 users from AMC were collected and integrated with the PHR data. We classified users according to whether they were continuous app users. We analyzed and compared their characteristics, patterns of hemoglobin A_1c (HbA_1c) levels, and the proportion of successful HbA_1c control. The following confounders were adjusted for HbA_1c pattern analysis and HbA_1c regulation proportion comparison: age, sex, first HbA_1c measurement, diabetes complications severity index score, sugar function data generation weeks, HbA_1c measurement weeks before MCMH 2.0 start, and generated sugar function data count.

RESULTS

The total number of MCMH 2.0 users was 64,932, with 7453 users having appropriate PHRs and diabetes criteria. The number of continuous and noncontinuous users was 133 and 7320, respectively. Compared with noncontinuous users, continuous users were younger (P<.001) and had a higher male proportion (P<.001). Furthermore, continuous users had more frequent HbA_1c measurements (P=.007), shorter HbA_1c measurement days (P=.04), and a shorter period between the first HbA_1c measurement and MCMH 2.0 start (P<.001). Diabetes severity-related factors were not statistically significantly different between the two groups. Continuous users had a higher decrease in HbA_1c (P=.02) and a higher proportion of regulation of HbA_1c levels to the target level (P=.01). After adjusting the confounders, continuous users had more decline in HbA_1c levels than noncontinuous users (P=.047). Of the users who had a first HbA_1c measurement higher than 6.5% (111 continuous users and 5716 noncontinuous users), continuous users had better regulation of HbA_1c levels with regard to the target level, 6.5%, which was statistically significant (P=.04).

CONCLUSIONS

By integrating and analyzing patient- and clinically generated data, we demonstrated that the continuous use of PHRs improved diabetes management outcomes. In addition, the HbA_1c reduction pattern was prominent in the PHR continuous user group. Although the continued use of PHRs has proven to be effective in managing diabetes, further evaluation of its effectiveness for various diseases and a study on PHR adherence are also required.

Autoimmune Thyroid Disease is Associated with a Lower Prevalence of Diabetic Retinopathy in Patients with Type 1 Diabetic Mellitus

Background and objectives: The aim of the study was to assess the correlation of autoimmune thyroid diseases (AITD) in patients with diabetes mellitus type 1 (DM1) with the occurrence of diabetic retinopathy (DR). Materials and Methods: The inclusion criteria for the study were: type 1 diabetes diagnosed on the basis of WHO criteria lasting at least a year, presence of AITD for at least a year, and age over 18 years. The control group consisted of patients without diagnosed AITD (DM1noAITD), selected according to age, BMI and DM1 duration. Anthropometric parameters, metabolic risk factors such as glycated hemoglobin (HbA1c), lipids and blood pressure, thyroid status and the presence of DR were assessed. Results: The study involved 200 patients with type 1 diabetes aged 36 ± 12 years, 70 men and 130 women. Patients from the study group (DM1AITD) had significantly lower creatinine concentration, significantly lower systolic blood pressure (SBP), glycated hemoglobin (HbA1c) percentage and triglyceride (TG) concentration, and higher high-density lipoprotein (HDL-cholesterol) concentration than the control group (DM1noAITD). There was a significantly lower chance of non-proliferative diabetic retinopathy (NPDR) among DM1AITD than in the control group. Conclusions: Patients with DM1 and AITD were metabolically better balanced, as evidenced by a significantly lower SBP, percentage of HbA1c and TG, as well as significantly higher HDL-cholesterol in this group. Patients with DM1 and AITD were significantly less likely to have NPDR than the control group.

Correlation between markers of renal function and sight-threatening diabetic retinopathy in type 2 diabetes: a longitudinal study in an Indian clinic population

INTRODUCTION

Previous epidemiological studies have reported on the prevalence of diabetic kidney disease (DKD) and diabetic retinopathy (DR) from India. The aim of this study is to evaluate the effect of DKD on the development of new-onset DR and sight-threatening diabetic retinopathy (STDR) in Asian Indians with type 2 diabetes (T2D).

RESEARCH DESIGN AND METHODS

The study was done on anonymized electronic medical record data of people with T2D who had undergone screening for DR and renal work-up as part of routine follow-up at a tertiary care diabetes center in Chennai, South India. The baseline data retrieved included clinical and biochemical parameters including renal profiles (serum creatinine, estimated glomerular filtration rate (eGFR) and albuminuria). Grading of DR was performed using the modified Early Treatment Diabetic Retinopathy Study grading system. STDR was defined as the presence of proliferative diabetic retinopathy (PDR) and/or diabetic macular edema. DKD was defined by the presence of albuminuria (≥30 µg/mg) and/or reduction in eGFR (<60 mL/min/1.73 m²). Cox regression analysis was used to evaluate the hazard ratio (HR) for DR and STDR.

RESULTS

Data of 19 909 individuals with T2D (mean age 59.6±10.2 years, mean duration of diabetes 11.1±12.1 years, 66.1% male) were analyzed. At baseline, DR was present in 7818 individuals (39.3%), of whom 2249 (11.3%) had STDR. During the mean follow-up period of 3.9±1.9 years, 2140 (17.7%) developed new-onset DR and 980 individuals with non-proliferative DR (NPDR) at baseline progressed to STDR. Higher serum creatinine (HR 1.5, 95% CI 1.3 to 1.7; p<0.0001), eGFR <30 mL/min/1.73 m² (HR 4.9, 95% CI 2.9 to 8.2; p<0.0001) and presence of macroalbuminuria >300 µg/mg (HR 3.0, 95% CI 2.4 to 3.8; p<0.0001) at baseline were associated with increased risk of progression to STDR.

CONCLUSIONS

DKD at baseline is a risk factor for progression to STDR. Physicians should promptly refer their patients with DKD to ophthalmologists for timely detection and management of STDR.

Assessment of diabetic retinopathy in type 1 diabetes in a diabetes care center in South India-Feasibility and awareness improvement study

The prevalence of youth-onset diabetes, both type 1 diabetes (T1D) and young-onset type 2 diabetes (YT2D) are gradually increasing in India. Early and repetitive screening for diabetic retinopathy (DR) is essential to provide timely management, and thereby prevent visual impairment due to the silent sight-threatening microvascular complication of diabetes. A study was undertaken at a diabetes care center in Chennai, south India, to assess the feasibility of screening for DR in T1D in a diabetes clinic and determine the burden of sight-threatening DR (STDR) in individuals with T1D. 315 people with T1D were screened for DR (mean age at onset of diabetes 12.3 ± 6.4 years) by digital retinal color photography, at the urban diabetes center, in a semi-urban and rural diabetes clinic. Counseling about diabetes and the importance of annual screening for retinopathy was provided by diabetes educators. Participants were reviewed after 6 months/1 year based on ophthalmologist's advice. DR was detected in 37.1% (n = 117), 42 (13%) of whom had STDR.Three-quarter participants were compliant with the annual follow-up retinal examination. The peer support group was established for participants with T1D and their families to foster interactions with service providers. The peer group meetings helped to increase the awareness of retinopathy among the parents and individuals with T1D. This narrative provides details of the study that shows that screening for DR among individuals with T1D in a diabetes clinic is a feasible model, irrespective of its location.

Pathological changes in the cellular structures of retina and choroidea in the early stages of alloxan-induced diabetes

AIM

To investigate the temporal sequence of pathological changes in the cellular structures of retina and choroidea in the early stages of diabetes in laboratory animals.

METHODS

Experimental type 1 diabetes was modeled by three intraperitoneal injections of an alloxan solution into 30 male nonlinear rats at 16 wk of age. The 30^th and 60^th days from the final alloxan injection were chosen as the endpoints. Light and electron microscopy and morphometric and immunohistochemical studies were performed on histological slices of eyeballs from experimental animals.

RESULTS

Diabetic disturbances progressed to 60 d of the experiment. Thus, in the retina, a partial destruction of photoreceptors accompanied by interstitial edema was observed. The morphometric analysis revealed a reduction in the thickness of the retina. A reduction in the number of blood vessels of the choroid with disturbances of the endothelial cells and the vascular walls and a persistent reduction in the number of melanocytes were observed. The number of proliferating Ki-67 positive cells decreased, and the number of macrophages increased with diabetes development.

CONCLUSION

The starting point in the development of destructive changes involves early reduction in the number of melanocytes of the choroidea and alterations in the retinal pigment epithelium.

Severity of diabetic retinopathy at the first ophthalmological examination in the Lebanese population

AIM

To determine the percentage and stage of diabetic retinopathy at the first ophthalmological examination after the patient's diagnosis with type 2 diabetes mellitus.

METHODS

A retrospective descriptive study was conducted at 'Clinique du Levant' hospital between 2006 and 2016. A total of 484 randomly selected patients were included. Data were collected and analyzed for selected variables (sex, age, sources of referral, and duration of diabetes).

RESULTS

In total, 119 (24.6%) patients had diabetic retinopathy. Among them, 43 had proliferative diabetic retinopathy (8.9%). About 16.7% of the included patients had macular edema, which was severe in 6.2%. The average age of patients was 62.1 years with an average of 8.3 years of diabetes. About 55% were men, while 45% were women. The patients with no referral source presented 8.9 years after the onset of diabetes, whereas patients referred by general practitioners and secondary medical professionals presented after 5.8 and 5 years, respectively (p < 0.05), but they represented only 23.2% of diabetics. Women presented earlier than men (7.3 versus 9.1 years; p = 0.012). About 82.6% were symptomatic, 44.1% had a visual impairment on Snellen charts that was severe in 11.2%. Also, 37.8% of the patients had a visually significant cataract. The duration of diabetes was the only dependent variable, p < 0.0001. The average age, sources of referral, and sex were not related to the severity of retinopathy.

CONCLUSION

Diabetics with a more severe diabetic retinopathy are presenting late to the ophthalmology clinics. There is a need to promote outreach programs for people with diabetes for early detection of diabetic retinopathy in Lebanon.

Screening for Diabetic Eye Disease among Samoan Adults: A Pilot Study

Introduction

The purpose of this study was to determine the prevalence of diabetic retinopathy in Samoa by piloting a retinal photography screening programme.

Methods

We performed a cross-sectional study of patients with diabetes who presented to the Tupua Tamasese Meaole eye clinic in Apia, Samoa, between May 2011 and September 2011. Study approval was granted by the National Health Service Board of Samoa, the Monash University Human Research Ethics Committee, and the study adhered to the Tenets of the Declaration of Helsinki. Following informed consent, data collection included patient demographics [age, area of residence (rural or urban)], type of diabetes, length of time since diagnosis, most recent random blood sugar and blood pressure levels. The subjects had three 45-degree retinal photographs taken in each eye with the Canon CR6-45NM camera. All gradable photographs were assessed for the presence of diabetic retinopathy or macular oedema using the International Clinical Diabetic Retinopathy Severity Scale and the International Clinical Diabetic Macular Oedema Severity scale, respectively.

Results

Two hundred and fourteen eyes from 107 subjects were examined during the study period, all of whom had type 2 diabetes mellitus. Diabetic retinopathy was present in 53.3% (114/214) of eyes, with 14.5% having proliferative retinopathy and 7.5% with severe non-proliferative retinopathy. Also, 25.2% (54/214) had some evidence of macular oedema with 11.7% (25/214) requiring treatment. A statistically significant relationship existed between the length of time since diagnosis and the severity of both retinopathy (p < 0.001) and macular oedema (p = 0.031). Blood pressure more than 150/85 mmHg was associated with higher levels of diabetic retinopathy (p = 0.03) and macular oedema (p = 0.02).

Conclusion

A comprehensive diabetic retinopathy screening programme is much needed in Samoa given the high prevalence of diabetic eye disease.