Type 2 diabetes mellitus and risk of open-angle glaucoma development in Koreans: An 11-year nationwide propensity-score-matched study

Nationwide cohort study of primary open angle glaucoma risk and cardiovascular factors among in Korean glaucoma suspects

This retrospective study investigated the risk of primary open-angle glaucoma (POAG) among individuals identified as glaucoma suspects and examined associated cardiovascular risk factors. We conducted a longitudinal, nationwide cohort study using data from the Korean National Health Insurance Service (KNHIS) and included 362,285 participants aged ≥ 40 years from the Korean National Health Screening Program (NHSP) without pre-existing POAG in 2009 and 2010. Of these, glaucoma suspects (n = 32,220) were defined as individuals with at least two recorded instances of the KCD code H400 for glaucoma suspect and no prior antiglaucoma medication prescriptions before health screening. The primary outcome was the diagnosis of POAG and the prescription of antiglaucoma medications. Over a 6-year follow-up, 4.92% of glaucoma suspects developed POAG. Through multivariate Cox regression analysis, glaucoma suspects with diabetes, hypertension, dyslipidemia, or coronary heart disease exhibited a greater risk of conversion to POAG than those without these comorbidities ([HR, 1.354; 95%CI, 1.201 to 1.527] for diabetes, [HR, 1.139; 95%CI, 1.019 to 1.273] for systemic hypertension, [HR, 1.128; 95%CI, 1.013 to 1.26] for dyslipidemia, [HR, 1.124, 95%CI, 1.007 to 1.254] for coronary heart disease).This nationwide study observed that among glaucoma suspects, having cardiovascular risk factors/disease was associated with higher risk of developing POAG.

Leptin Receptor Deficiency-Associated Diabetes Disrupts Lacrimal Gland Circadian Rhythms and Contributes to Dry Eye Syndrome

Purpose

This study investigated the impact of hyperglycemia in type 2 diabetes mellitus (T2DM) on the circadian rhythms and function of lacrimal glands (LGs) in contributing to dry eye syndrome. We assessed the effects of hyperglycemia on circadian gene expression, immune cell recruitment, neural activity, and metabolic pathways, and evaluated the effectiveness of insulin in restoring normal LG function.

Methods

Using a T2DM mouse model (db/db mice), circadian transcriptomic changes in LGs were analyzed through RNA sequencing over a 24-hour period. Rhythmic expression of core clock genes, immune and neural activity, and metabolic pathways were evaluated. The effects of insulin treatment on these parameters were also assessed.

Results

Hyperglycemia disrupted the circadian expression of core clock genes in LGs, leading to a 50% reduction in rhythmic gene expression. This was associated with altered immune cell recruitment, impaired neural activity, and metabolic changes. Insulin treatment lowered blood glucose levels but did not restore normal circadian function or tear secretion, exacerbating dry eye syndrome in diabetic mice.

Conclusions

T2DM significantly disrupts circadian rhythms and function in lacrimal glands, contributing to dry eye syndrome. The limited efficacy of insulin in restoring circadian regulation suggests that hyperglycemia-induced dysfunction in LGs is not solely dependent on blood glucose levels, highlighting the need for therapies targeting circadian rhythms in diabetic ocular complications.

Prevalence and Risk Factors of Fundus Pathology in Patients with Type 2 Diabetes in a Northeastern Chinese Cohort

PURPOSE

To assess the prevalence of and risk factors for fundus pathology in patients with type 2 diabetes mellitus (T2DM) in a cohort from northeastern China.

METHODS

Patients were included from the Fushun Diabetic Retinopathy Cohort Study. Patients aged ≥ 30 years with T2DM were recruited between July 2012 and May 2013. Fundus pathology included retinal vascular occlusion (RVO), age-related macular degeneration (AMD), macular pathology, pathologic myopia (PM) and glaucomatous optic atrophy (GOA).

RESULTS

A Total of 1998 patients with gradable fundus photographs were included in this study, of whom 388 (19.42%) had fundus pathology regardless of whether they had diabetic retinopathy (DR). There were 187 (9.36%) patients with AMD, 97 (4.85%) with GOA, 67 (3.35%) with macular pathology, 35 (1.75%) with PM and 23 (1.15%) with RVO. Advanced age was significantly associated with AMD (odds ratio (OR), 95% confidence interval (CI): 1.03, 1.01-1.05), macular pathology (OR, 95% CI: 1.06, 1.03-1.09) and GOA (OR, 95% CI: 1.06, 1.04-1.09). A wider central retinal arteriolar equivalent was protective against PM (OR, 95% CI: 0.78, 0.66-0.92). Wider central retinal venular equivalent was a protective factor for PM (OR, 95% CI: 0.75, 0.68-0.82) and GOA (OR, 95% CI: 0.93, 0.87-0.99).

CONCLUSIONS

One-fifth of these patients in northeast China with T2DM had fundus pathology regardless of whether they had DR, indicating the importance of early screening and long-term follow-up.

Photocoagulation or sham laser in addition to conventional anti-VEGF therapy in macular edema associated with TelCaps due to diabetic macular edema or retinal vein occlusion (TalaDME): a study protocol for a multicentric, French, two-group, non-commercial, active-control, observer-masked, non-inferiority, randomized controlled clinical trial

BACKGROUND

Macular edema (ME) results from hyperpermeability of retinal vessels, leading to chronic extravasation of plasma components into the retina and hence potentially severe visual acuity loss. Current standard of care consists in using intravitreal injections (IVI), which results in a significant medical and economic burden. During diabetic retinopathy (DR) or retinal vein occlusion (RVO), it has recently been shown that focal vascular anomalies (capillary macro-aneurysms, also termed TelCaps) for telangiectatic capillaries may play a central role in the onset, early recurrence, and/or persistence of ME. Since targeted photocoagulation of TelCaps may improve vision, identification, and photocoagulation of TelCaps, it may represent a way to improve management of ME.

OBJECTIVE

The Targeted Laser in (Diabetic) Macular Edema (TalaDME) study aims to evaluate whether ICG-guided targeted laser (IGTL), in association with standard of care by IVI, allows reducing the number of injections during the first year of treatment compared with IVI only, while remaining non-inferior for visual acuity.

METHODS

TalaDME is a French, multicentric, two-arms, randomized, sham laser-controlled, double-masked trial evaluating the effect of photocoagulation of TelCaps combined to IVI in patients with ME associated with TelCaps. Patients with vision loss related to center involved ME secondary to RVO or DR and presenting TelCaps are eligible. Two hundred and seventy eyes of 270 patients are randomized in a 1:1 ratio to standard care, i.e., IVI of anti-VEGF solely (control group) or combined with IGTL therapy (experimental group). Stratification is done on the cause of ME (i.e., RVO versus diabetes). Anti-VEGF IVI are administered to both groups monthly for 3 months (loading dose) and then with a pro re nata regimen with a monthly follow-up for 12 months. The primary endpoint will be the number of IVI and the change in visual acuity from baseline to 12 months. Secondary endpoints will be the changes in central macular thickness, impact on quality of life, cost of treatment, and incremental cost-utility ratio in each groups.

KEY SAFETY

Rare but severe AE linked to the use of IVI and laser, and previously described, are expected. In the sham group, rescue laser photocoagulation may be administered by the unmasked investigator if deemed necessary at month 3.

DISCUSSION

The best management of ME associated with TelCaps is debated, and there have been no randomized study designed to answer this question. Given the fact that TelCaps may affect 30 to 60% of patients with chronic ME due to DR or RVO, a large number of patients could benefit from a specific management of TelCaps. TalaDME aims to establish the clinical and medico-economic benefits of additional targeted laser. The results of TalaDME may raise new recommendations for managing ME and impact healthcare costs.

TRIAL REGISTRATION

EudraCT: 2018-A00800-55/ NCT03751501. Registration date: Nov. 23, 2018.

Possible Causal Association between Type 2 Diabetes and Glycaemic Traits in Primary Open-Angle Glaucoma: A Two-Sample Mendelian Randomisation Study

Existing literature suggests a controversial relationship between type 2 diabetes mellitus (T2D) and glaucoma. This study aimed to examine the potential causal connection between T2D and glycaemic traits (fasting glucose [FG] and glycated haemoglobin [HbA1c] levels) as exposures to primary open-angle glaucoma (POAG) in multi-ethnic populations. Single-nucleotide polymorphisms associated with exposure to T2D, FG, and HbA1c were selected as instrumental variables with significance (p < 5.0 × 10-8) from the genome-wide association study (GWAS)-based meta-analysis data available from the BioBank Japan and the UK Biobank (UKB). The GWAS for POAG was obtained from the meta-analyses of Genetic Epidemiology Research in Adult Health and Aging and the UKB. A two-sample Mendelian randomisation (MR) study was performed to assess the causal estimates using the inverse-variance weighted (IVW) method, and MR-Pleiotropy Residual Sum and Outlier test (MR-PRESSO). Significant causal associations of T2D (odds ratio [OR] = 1.05, 95% confidence interval [CI] = [1.00-1.10], p = 0.031 in IVW; OR = 1.06, 95% CI = [1.01-1.11], p = 0.017 in MR-PRESSO) and FG levels (OR = 1.19, 95% CI = [1.02-1.38], p = 0.026 in IVW; OR = 1.17, 95% CI = [1.01-1.35], p = 0.041 in MR-PRESSO) with POAG were observed, but not in HbA1c (all p > 0.05). The potential causal relationship between T2D or FG and POAG highlights its role in the prevention of POAG. Further investigation is necessary to authenticate these findings.

Association between metformin use and the risk of developing open-angle glaucoma among patients with diabetes: a retrospective cohort study and meta-analysis

PURPOSE

Recent studies examining the neuroprotective effects of metformin on open-angle glaucoma (OAG) have failed to provide consistent results. In this study, we investigated the association between metformin use and OAG.

METHODS

Data were obtained from a sample cohort of the Korean National Health Insurance database. Patients diagnosed with type-2 diabetes (T2DM) between 2004 and 2013 were included. We performed propensity score-matched analysis in a matched cohort (N = 20,646). The risk of the newly developed OAG was estimated using a Cox proportional hazards model. Including the present study, the meta-analysis included five studies to calculate the pooled risk for OAG based on metformin use.

RESULTS

In the adjusted model, the analysis revealed no statistical association between metformin use and OAG incidence (hazard ratio [HR] 1.05; 95% confidence interval [CI] 0.79-1.40; P = 0.738). The highest tercile of metformin use demonstrated no statistical significance (HR 0.93 [95% CI 0.63-1.37]; P = 0.703). No significant dose-dependent association was observed between the cumulative dose and incidence of OAG (P-value for trend = 0.336). In a meta-analysis of four published articles and the present study, the common-effects and random-effects models indicated conflicting results in terms of significance. The random effects model demonstrated no significant association (pooled risk ratio 0.53; 95% CI 0.24-1.19; P = 0.123).

CONCLUSION

We found no significant association between metformin use and OAG incidence in patients with T2DM in this population-based cohort study and meta-analysis. Further studies are needed to investigate the association between metformin use and the risk of OAG among patients with T2DM.

Dissecting causal associations of type 2 diabetes with 111 types of ocular conditions: a Mendelian randomization study

Background

Despite the well-established findings of a higher incidence of retina-related eye diseases in patients with diabetes, there is less investigation into the causal relationship between diabetes and non-retinal eye conditions, such as age-related cataracts and glaucoma.

Methods

We performed Mendelian randomization (MR) analysis to examine the causal relationship between type 2 diabetes mellitus (T2DM) and 111 ocular diseases. We employed a set of 184 single nucleotide polymorphisms (SNPs) that reached genome-wide significance as instrumental variables (IVs). The primary analysis utilized the inverse variance-weighted (IVW) method, with MR-Egger and weighted median (WM) methods serving as supplementary analyses.

Results

The results revealed suggestive positive causal relationships between T2DM and various ocular conditions, including "Senile cataract" (OR= 1.07; 95% CI: 1.03, 1.11; P=7.77×10-4), "Glaucoma" (OR= 1.08; 95% CI: 1.02, 1.13; P=4.81×10-3), and "Disorders of optic nerve and visual pathways" (OR= 1.10; 95% CI: 0.99, 1.23; P=7.01×10-2).

Conclusion

Our evidence supports a causal relationship between T2DM and specific ocular disorders. This provides a basis for further research on the importance of T2DM management and prevention strategies in maintaining ocular health.

Association between atrial fibrillation and the risk of glaucoma development: a 12-year Nationwide cohort study

OBJECTIVE

To investigate the risk of glaucoma development in patients with atrial fibrillation (A-fib) using Korean National Health Insurance Service data.

METHODS

The present study used a National Sample Cohort consisting of approximately one million random subjects who were tracked from 2002 to 2013 (12 years). Newly diagnosed glaucoma and A-fib were included based on the Korean Classification of Disease codes. The A-fib group consisted of patients who received an initial A-fib diagnosis between January 2003 and December 2007 as an index period (n = 8765). The control group (n = 43,352) was selected using a 1:5 propensity-score matching for social and demographic factors. Each subject was followed up until 2013. Multivariate Cox proportional hazard regression analysis was performed to compare the risk of glaucoma development between the A-fib group and the control group.

RESULTS

The rate of glaucoma development was 3.54% in the A-fib group and 2.96% in the control group (P < 0.0001). A-fib increased the risk of glaucoma development [hazard ratio = 1.31; 95% confidence interval (CI): 1.15 to 1.48] after adjusting for age, sex, comorbidities, residence, household income, and year of enrollment. In multivariable Cox regression analysis, patients with comorbidity of diabetes mellitus and chronic renal failure and those aged ≥50 years showed significantly higher risk of glaucoma development (all P < 0.001).

CONCLUSIONS

A-fib was significantly associated with the development of glaucoma after adjusting for potential confounding factors. Physicians may need to monitor patients with A-fib carefully for possible glaucoma development.

Association of glaucoma and lifestyle with incident cardiovascular disease: a longitudinal prospective study from UK Biobank

The shared pathophysiological features of the cerebrovascular disease (CVD) and glaucoma suggest an association between the two diseases. Using the prospective UK Biobank cohort, we examined the associations between glaucoma and incident CVD and assessed the extent to which a healthy lifestyle reduced the CVD risk in subjects with glaucoma, using a scoring system consisting of four factors: current smoking, obesity, regular physical activity, and a healthy diet. During a mean follow-up time of 8.9 years, 22,649 (4.9%) incident CVD cases were documented. Multivariable Cox regression analyses revealed that subjects with glaucoma were significantly more likely to exhibit incident CVD (hazard ratio [HR]:1.19, 95% confidence interval [CI] 1.03-1.37; p = 0.016) than controls. In the further subgroup analyses, glaucoma increased incident CVD risk both in the young (40-55 years) and the old (56-70 years) and in both sexes, with higher risk in the young (HR: 1.33, CI 1.02-1.74) and female subjects (HR: 1.32, CI 1.14-1.52). When we analyze the associations between glaucoma and incident CVD by lifestyle factors, the highest absolute risks were observed in individuals with both glaucoma and an unhealthy lifestyle (HR: 2.66, CI 2.22-3.19). In conclusion, glaucoma was an independent risk factor for incident CVD. A healthy lifestyle was associated with a substantially lower risk for CVD incidence among adults with glaucoma.

Glucagon-like peptide 1 receptor agonist use is associated with reduced risk for glaucoma

BACKGROUND/AIMS

Glucagon-like peptide-1 receptor (GLP-1R) agonists regulate blood glucose and are commonly used to treat type 2 diabetes mellitus. Recent work showed that treatment with the GLP-1R agonist NLY01 decreased retinal neuroinflammation and glial activation to rescue retinal ganglion cells in a mouse model of glaucoma. In this study, we used an insurance claims database (Clinformatics Data Mart) to examine whether GLP-1R agonist exposure impacts glaucoma risk.

METHODS

A retrospective cohort of patients who initiated a new GLP-1R agonist was 1:3 age, gender, race, classes of active diabetes medications and year of index date matched to patients who initiated a different class of oral diabetic medication. Inverse probability of treatment weighting (IPTW) was used within a multivariable Cox proportional hazard regression model to test the association between GLP-1R agonist exposure and a new diagnosis of primary open-angle glaucoma, glaucoma suspect or low-tension glaucoma.

RESULTS

Cohorts were comprised of 1961 new users of GLP-1R agonists matched to 4371 unexposed controls. After IPTW, all variables were balanced (standard mean deviation <|0.1|) between cohorts. Ten (0.51%) new diagnoses of glaucoma were present in the GLP-1R agonist cohort compared with 58 (1.33%) in the unexposed controls. After adjustment, GLP-1R exposure conferred a reduced hazard of 0.56 (95% CI: 0.36 to 0.89, p=0.01), suggesting that GLP-1R agonists decrease the risk for glaucoma.

CONCLUSIONS

GLP-1R agonist use was associated with a statistically significant hazard reduction for a new diagnosis of glaucoma. Our findings support further investigations into the use of GLP-1R agonists in glaucoma prevention.

Type 2 Diabetes, Fasting Glucose, Hemoglobin A1c Levels and Risk of Primary Open-Angle Glaucoma: A Mendelian Randomization Study

Purpose

To evaluate the potential causal associations between type 2 diabetes and fasting glucose and HbA1c levels and the risk of primary open-angle glaucoma (POAG) in European and East Asian populations.

Methods

We selected genetic variants (P < 5 × 10⁻⁸) for type 2 diabetes (898,130 Europeans; 433,540 East Asians), fasting glucose, and HbA1c (196,991 Europeans; 36,584 East Asians) from three meta-analyses of genome-wide association studies (GWAS). The GWAS for POAG provided summary statistics (192,702 Europeans; 46,523 East Asians). Mendelian randomization (MR) analysis was accomplished using the inverse variance–weighted method, weighted-median method, MR Egger method, and MR-Pleiotropy RESidual Sum and Outlier test.

Results

Genetically predicted type 2 diabetes was potentially positively associated with POAG in the European ancestry (body mass index [BMI]–unadjusted: odds ratio [OR] = 1.07, 95% confidence interval [CI], 1.01–1.14, P = 0.028; BMI-adjusted: OR = 1.07, 95% CI, 1.01–1.15, P = 0.035), but not in the East Asian ancestry (BMI-unadjusted: OR = 1.01, 95% CI, 0.95–1.06, P = 0.866; BMI-adjusted: OR = 1.00, 95% CI, 0.94–1.05, P = 0.882). There was no evidence to support a causal association of fasting glucose (European: OR = 1.19, P = 0.157; East Asian: OR = 0.94, P = 0.715) and HbA1c (European: OR = 1.27, P = 0.178; East Asian: OR = 0.85, P = 0.508) levels with POAG.

Conclusions

The causal effect of type 2 diabetes on the risk of POAG is different in European and East Asian populations. The point estimates of fasting glucose and Hb1Ac with POAG are large but not statistically significant, which prompts the question of statistical power.

Role of ocular blood flow in normal tension glaucoma

Background

Normal tension glaucoma (NTG) is a multifactorial disease in the pathogenesis of which intraocular pressure (IOP)-independent factors play a key role.

Main text

There is considerable evidence that impairment of the ocular blood flow (OBF) is involved both in the onset and progression of this disease. With the development of the hypothesis of OBF in NTG, various imaging techniques have been developed to evaluate the OBF and blood vessels. Moreover, vascular dysregulation, which is a main factor in Flammer syndrome, was frequently observed in NTG patients. Disturbed OBF leads to increased oxidative stress, which plays an important role in the pathogenesis of glaucomatous optic neuropathy. These results suggested that IOP-independent management may provide alternative treatment options for NTG patients.

Conclusions

In this review, we mainly focus on the mechanisms of the abnormal OBF in NTG.

Development of Open-Angle Glaucoma in Adults With Seropositive Rheumatoid Arthritis in Korea

IMPORTANCE

Although evidence is emerging that autoimmunity may be associated with neurodegeneration in glaucoma (beyond intraocular pressure-mediated damage), there is limited evidence connecting rheumatoid arthritis (RA), the most common autoimmune disease, with the risk of developing primary open-angle glaucoma (POAG).

OBJECTIVE

To investigate whether RA is associated with increased risk of POAG among Korean older adults.

DESIGN, SETTING, AND PARTICIPANTS

A nationwide propensity-matched cohort study was conducted using data from the Korean National Health Insurance Service-Senior cohort from 2002 to 2013. Data analysis was performed from November 2020 to July 2021.

EXPOSURES

New onset RA.

MAIN OUTCOMES AND MEASURES

The main outcome was development of POAG. The Kaplan-Meier method was used to calculate the cumulative incidence of POAG, and the incidence rate of POAG was estimated using a Poisson regression. A Cox proportional hazards regression model was used to investigate associations between RA and risk of POAG.

RESULTS

Among 10 245 participants, 7490 (73.1%) were women, and the mean (SD) age was 67.70 (4.84) years. A total of 2049 patients with incident seropositive RA and 8196 time-dependent, propensity score-matched, risk-set controls were included. POAG developed in 86 of 2049 patients with RA and 254 of 8196 matched controls. The cumulative incidence of POAG was higher in the RA cohort than in the matched controls. In the RA cohort, the incidence rate of POAG was 981.8 cases per 100 000 person years (95% CI, 794.3-1213.7 cases per 100 000 person years), whereas in the matched controls, the incidence rate was 679.5 cases per 100 000 person years (95% CI, 600.8-768.3 cases per 100 000 person years). Patients with RA were more likely to develop POAG than the matched controls (hazard ratio [HR], 1.44; 95% CI, 1.13-1.84). Increased POAG risk in the RA cohort was predominantly observed 2 years into the follow-up period (HR, 1.83; 95% CI, 1.28-2.61) and in those aged 75 years or older (HR, 2.12; 95% CI, 1.34-3.35).

CONCLUSIONS AND RELEVANCE

These findings suggest that RA is associated with a higher risk of developing POAG, especially within 2 years after diagnosis or among patients aged 75 years or older. There may be a common pathophysiological pathway between RA and POAG that is possibly immune mediated, and the nature of this association warrants further investigation.

Glucagon-Like Peptide 1 Receptor Agonists – Potential Game Changers in the Treatment of Glaucoma?

Glaucoma is a common ocular neurodegenerative disease characterized by the progressive loss of retinal ganglion cells and their axons. It is the most common cause of irreversible blindness. With an increasing number of glaucoma patients and disease progression despite treatment, it is paramount to develop new and effective therapeutics. Emerging new candidates are the receptor agonists of the incretin hormone glucagon-like-peptide-1 (GLP-1), originally used for the treatment of diabetes. GLP-1 receptor (GLP-1R) agonists have shown neuroprotective effects in preclinical and clinical studies on neurodegenerative diseases in both the brain (e.g., Alzheimer’s disease, Parkinson’s disease, stroke and diabetic neuropathy) and the eye (e.g., diabetic retinopathy and AMD). However, there are currently very few studies investigating the protective effects of GLP-1R agonists in the treatment of specifically glaucoma. Based on a literature search on PubMed, the Cochrane Library, and ClinicalTrials.gov, this review aims to summarize current clinical literature on GLP-1 receptor agonists in the treatment of neurodegenerative diseases to elucidate their potential in future anti-glaucomatous treatment strategies.

Relationship between Using Fibrate and Open-Angle Glaucoma in Hyperlipidemic Patients: A Population-Based Cohort Study

Background: This study aimed to investigate the associated risk between using fibrate and open-angle glaucoma (OAG) in hyperlipidemic patients from the National Health Insurance Research Database (NHIRD). Methods: We collected data over a 16-year period from the NHIRD, and used the Fisher’s exact test and Pearson chi-square test to analyze variables. Adjusted hazard ratios (aHR) were used to examine the risk factors for disease development. We applied Kaplan–Meier analysis to compare the cumulative incidence of OAG. Results: A total of 10,011 patients using fibrate were enrolled in the study cohort, and 40,044 patients not using fibrate were enrolled in the control cohort. The incidence of OAG was lower in the study cohort than in the control cohort (aHR = 0.624, p = 0.007). The overall incidence of OAG was 463.02 per 100,000 person-years in the study cohort and 573.65 per 100,000 person-years in the control cohort. We used the Kaplan–Meier method to calculate the cumulative risk of developing OAG. The results revealed that after using fibrate for over seven years, the study cohort had a greatly lower rate of developing OAG than the control cohort (log-rank test p = 0.050). Conclusions: Our studies showed that using fibrate for over seven years may lead to a lower risk of OAG in patients with hyperlipidemia. Nevertheless, further prospective studies that comprehensively investigate the relationship between using fibrate and OAG are needed.

Eye disorders other than diabetic retinopathy in patients with diabetes

AIM

While diabetic retinopathy is the most specific complication of chronic hyperglycaemia, numerous other ocular conditions also can involve the eyes of people with diabetes. Cataract, glaucoma, age-related macular degeneration, retinal vascular occlusion, and acute ischaemic optic neuropathy combine to impair vision in people with diabetes, especially when they are old. This report provides a critical analysis and an overview of the current knowledge of the main ocular disorders (excluding diabetic retinopathy) and their association in patients with diabetes.

METHODS

A literature search strategy was conducted for all English-language literature with a systematic review of key references until 2021.

RESULTS

Patients with diabetes have a high-to-moderate increased risk for most of the usual ocular disorders we reviewed with the exception of age-related macular degeneration. Exposure to chronic hyperglycaemia promotes the development of many eye disorders while acute glucose changes are involved in refractive disorders, diabetic papillopathy and acute cataract.

CONCLUSION

Diabetes, beyond diabetic retinopathy, increases the risk of numerous eye disorders leading to low vision with implications for daily diabetes management. Even in the absence of clearly demonstrated benefit from glucose control in all eye conditions, achieving good glycaemic control and adherence to diabetes treatment will likely help avoid an additional risk of visual impairment in people with diabetes. In perspective, interesting findings suggesting a preventive effect of metformin use on age-related macular degeneration occurrence justify further studies.

Association Between Diabetes, Diabetic Retinopathy, and Glaucoma

PURPOSE OF REVIEW

The strength of the relationship between diabetes, diabetic retinopathy (DR), and glaucoma remains controversial. We review evidence supporting and refuting this association and explore mechanistic pathological and treatment relationships linking these diseases.

RECENT FINDINGS

While studies have shown diabetes/DR may increase the risk for glaucoma, this remains inconsistently demonstrated. Diabetes/DR may contribute toward glaucomatous optic neuropathy indirectly (either by increasing intraocular pressure or vasculopathy) or through direct damage to the optic nerve. However, certain elements of diabetes may slow glaucoma progression, and diabetic treatment may concurrently be beneficial in glaucoma management. Diabetes plays a significant role in poor outcomes after glaucoma surgery. While the relationship between diabetes/DR and glaucoma remains controversial, multiple mechanistic links connecting pathophysiology and management of diabetes, DR, and glaucoma have been made. However, a deeper understanding of the causes of disease association is needed.

Association Between Chronic Renal Disease and the Risk of Glaucoma Development: A 12-year Nationwide Cohort Study

Purpose

The purpose of this study was to present the results of our investigation into the risk of glaucoma development in patients with chronic renal disease (CRD).

Methods

The present retrospective cohort study used the Korean National Health Insurance Service data, which consisted of 1,025,340 random subjects who were tracked from 2002 to 2013. Newly diagnosed glaucoma and CRD were included on the basis of the Korean Classification of Disease codes. The CRD group consisted of patients who received an initial CRD diagnosis between January 2003 and December 2007 as an index period (n = 3640). The control group (n = 17,971) was selected using 1:5 propensity-score matching using social and demographic factors, along with the year of enrollment. Each group subject was followed until 2013. We used multivariate Cox proportional hazard regression analysis to compare the risk of glaucoma development between the two groups.

Results

Glaucoma consecutively developed in 4.3% in the CRD group and 2.8% in the control group (P < 0.0001). CRD increased the risk of glaucoma development (hazard ratio [HR] = 1.63, 95% confidence interval [CI] = 1.34–1.98] after adjusting for age, sex, comorbidities, residence, household income, and the year of enrollment. In multivariate Cox regression analysis, patients with comorbidity of hypertension, diabetes mellitus, or aged ≥ 50 years showed a significantly higher risk of glaucoma development (all P < 0.008).

Conclusions

A significant association between CRD and following development of glaucoma was revealed after adjusting the potential confounding factors.

Vascular density of optic nerve head in diabetic retinopathy using optical coherence tomography angiography

PURPOSE

To measure optic nerve head (ONH) blood perfusion using optical coherence tomography angiography (OCTA) at various stages of diabetic retinopathy (DR).

METHODS

One hundred seventy six eyes of 94 patients included in this retrospective single-centre cross-sectional study. The subjects were studied in normal, no diabetic retinopathy (NDR), non-proliferative diabetic retinopathy (NPDR) and proliferative retinopathy (PDR) groups. The eyes were subjected to AngioDisc ONH imaging using OCTA for papillary (Disc) and peripapillary (RPC) vascular density (VD) evaluation.

RESULTS

The mean age of the participants was 56.08 ± 8.87 years and 34 (36.2 percent) were male. With increased DR severity, a statistically significant decrease in peripapillary VD was found. The study showed that only VD of the whole RPC (W-RPC) could be a valid biomarker in the staging assessment. VD of RPC, in all subsections, was considerably different from normal cases in the PDR group. Visual acuity was correlated with whole image ONH VD. The duration of DM, FBS, hyperlipidemia and DME had no effect on the ONH perfusion.

CONCLUSIONS

The study showed that only the W-RPC VD could be a reasonable marker in the staging assessment. VDs assessed by OCTA can be useful for assessing and tracking early ONH changes in DR patients.

Fasting plasma glucose level and the risk of open angle glaucoma: Nationwide population-based cohort study in Korea

Background

The level of fasting plasma glucose (FPG) is positively associated with intraocular pressure. Diabetes causes early structural changes of retina, especially on ganglion cell layer. In this regard, the FPG level itself may also show an independent association with open angle glaucoma (OAG) development in general population. Herein, we investigate the association of the FPG level with the incidence of OAG.

Methods

Using nationally representative data from the Korean National Health Insurance System, 374,376 subjects ≥40 years of age without OAG who underwent health examinations from 2009 to 2013 were enrolled and followed to the end of 2014. Incident cases of OAG using the International Classification of Diseases 10 codes and medication information were analyzed based on the levels of FPG.

Results

Subjects with the highest FPG level (≥160 mg/dL), compared with the lowest level (<80 mg/dL), showed a higher hazard ratio (HR) [2.189; 95% confidence interval (CI): 1.779–2.695; P for trend < 0.001] for OAG after adjustments for age and sex. This result persisted after further adjustments for the presence of type 2 diabetes, current smoking, drinking, and exercise habits, diastolic blood pressure, body mass index (BMI), and total cholesterol level (HR: 1.588; 95% CI: 1.268–1.989; P for trend < 0.001). The positive association between the FPG level and the incidence of OAG was distinct in subjects 40–64 years of age, those with a BMI <25 kg/m², and those without hypertension (HR 2.022; 95% CI: 1.494–2.736; P for trend <0.001: HR 1.817; 95% CI: 1.372–2.407; P for trend < 0.001: HR 1.706; 95% CI: 1.180–2.467; P for trend <0.001, respectively).

Conclusions

This nationwide population-based cohort study showed that the fasting glucose was associated with an increased risk of OAG. These findings suggest that subjects with high FPG levels require special attention when screening for glaucoma.

Peripapillary microvasculature in patients with diabetes mellitus: An optical coherence tomography angiography study

To evaluate changes in peripapillary microvascular parameters in diabetes mellitus (DM) patients using optical coherence tomography angiography (OCTA). Seventy-one diabetic patients (40 in the no diabetic retinopathy [DR] group and 31 in the non-proliferative DR [NPDR] group) and 50 control subjects. OCTA (Zeiss HD-OCT 5000 with AngioPlex) 6 × 6 mm scans centered on the optic disc were analyzed. Peripapillary vessel density (VD), perfusion density (PD) in superficial capillary plexus (SCP) were automatically calculated. The average macular ganglion cell-inner plexiform layer (mGC-IPL) and peripapillary retinal nerve fiber layer (pRNFL) thicknesses of the no DR and NPDR groups were significantly thinner than those of the control group. The no DR and NPDR groups showed lower peripapillary VD and PD in SCP compared with the control group. Using univariate regression analyses, the average mGC-IPL thickness, the pRNFL thickness, the no DR group and NPDR group were significant factors that affected the peripapillary VD and PD in SCP. Multivariate regression analyses showed that the grade of DR was a significant factor affecting the peripapillary VD and PD in SCP. OCTA revealed that peripapillary microvascular parameters in the no DR and NPDR groups were lower than those of normal controls. The peripapillary VD and PD in SCP were correlated with the mGC-IPL thickness, the pRNFL thickness, and the no DR and NPDR groups. Changes in peripapillary OCTA parameters may help with understanding the pathophysiology of DM and evaluating a potentially valuable biomarker for patients with subclinical DR.

Community care for diabetic retinopathy and glaucoma in India: A panel discussion

Diabetic retinopathy (DR) and glaucoma are emerging causes of blindness and visual impairment in India and the world. Both diseases do not have any early warning symptoms, and once the symptoms appear, the diseases are reasonably advanced. Because of the long-standing nature of the diseases, one cannot adopt the cataract detection and treatment model so successfully developed in India. It requires an altogether different approach for screening and related infrastructure including human capital development. The solutions developed to reduce the burden of DR/glaucoma should be customized to urban, semi-urban, and rural areas. Greater advocacy, improving the health-seeking behavior, development of infrastructure and skilled personnel appropriate for the points of care, and an emphasis in comprehensive eye care are some of the solutions.