Risk factors for clinically significant macular edema in a multi-ethnics population with type 2 diabetes

Choroidal thickness in children with type 1 diabetes depending on the pubertal status and metabolic parameters analyzed by optical coherence tomography

To assess choroidal thickness (CT) in children with type 1diabetes (T1D) regarding their pubertal status and seek for factors influencing this parameter, using optical coherence tomography.

MATERIAL AND METHODS

333 eyes out of 167 children with T1D without symptoms of diabetic retinopathy (mean age 12.81 ± 3.63 years, diabetes duration 4.59 ± 3.71 years) were enrolled. CT in all quadrants was evaluated. The studied population was divided into three groups: prepubertal, pubertal and postpubertal. The multivariate regression model was carried out using all metabolic parameter and then it was built using only the significant ones.

RESULTS

Significant differences in CT between males and females, except nasal and superior quadrants were observed. We revealed significant differences in CT between the three independent groups (Chi-square 18.6, p < 0.0001). In the statistically significant multiple regression model (R = 0.9, R² = 0.82, p < 0.0000), the serum level of free thyroxine, triiodothyronine, total hemoglobin, uric acid, low- and high-density cholesterol, daily insulin dose per kilogram, weight and level of vitamin D were significant.

CONCLUSION

In our studied group CT increases during puberty. Metabolic parameters such as cholesterol, uric acid, thyroid hormones, and hemoglobin concentration even within the normal range, significantly influence the CT, and these factors likely affect other blood vessels in the body.

Prevalence of and risk factors for diabetic retinopathy and diabetic macular edema in patients with early and late onset diabetes mellitus

PURPOSE

To compare the prevalence of diabetic retinopathy (DR) and diabetic macular edema (DME), as well as their risk factors in patients with early onset diabetes (EOD, ≤40 years) and late onset diabetes (LOD, >40 years).

METHODS

Patients were recruited from a community-based study, Fushun Diabetic Retinopathy Cohort Study (FS-DIRECT), conducted between July 2012 and May 2013 in China. The presence and severity of the DR and DME were determined by a modified Early Treatment Diabetic Retinopathy Study (ETDRS) retinopathy scale of six-field fundus photographs.

RESULTS

A total of 1932 patients (796 male, 41.2%) with gradable fundus photography were included. The prevalence of any DR and DME was 67.0% (95% confidence interval [CI]: 60.3-73.7%) and 39.3% (95% CI: 32.1-46.5%) in the EOD patients respectively, which were both significantly higher than that in the LOD patients (DR: 41.9%, 39.6-44.2%, p<0.001; DME: 14.4%, 12.7-16.1%, p<0.001). Insulin use was associated with both presence of DR and DME in both EOD and LOD patients. Besides insulin use, high level of income (odds ratio [OR], 95% CI: 0.05, 0.01-0.51) was negatively associated with DR, and higher high density lipoprotein (OR, 95% CI: 4.14, 1.44-11.91) was associated with DME, among EOD patients.

CONCLUSION

In this sample of patients with type 2 diabetes, both the prevalence of DR and DME were apparently higher in patients who developed diabetes ≤40 years of age than those who developed it later.

'Statins in retinal disease'

Statins are known for their blood cholesterol-lowering effect and are widely used in patients with cardiovascular and metabolic diseases. Research over the past three decades shows that statins have diverse effects on different pathophysiological pathways involved in angiogenesis, inflammation, apoptosis, and anti-oxidation, leading to new therapeutic options. Recently, statins have attracted considerable attention for their immunomodulatory effect. Since immune reactivity has been implicated in a number of retinal diseases, such as uveitis, age-related macular degeneration (AMD) and diabetic retinopathy, there is now a growing body of evidence supporting the beneficial effects of statins in these retinopathies. This review evaluates the relationship between statins and the pathophysiological basis of these diseases, focusing on their potential role in treatment. A PubMed database search and literature review was conducted. Among AMD patients, there is inconsistent evidence regarding protection against development of early AMD or delaying disease progression; though they have been found to reduce the risk of developing choroidal neovascular membranes (CNV). In patients with retinal vein occlusion, there was no evidence to support a therapeutic benefit or a protective role with statins. In patients with diabetic retinopathy, statins demonstrate a reduction in disease progression and improved resolution of diabetic macular oedema (DMO). Among patients with uveitis, statins have a protective effect by reducing the likelihood of uveitis development.

The Correlation between Changes in Biochemical Parameters and Central Macular Thickness in Patients with Non-Proliferative Diabetic Retinopathy

This study aimed at evaluating the correlation between changes in Hemoglobin A1c (HbA1c) and fasting serum lipids, and Central Macular Thickness (CMT) in patients with Non-Proliferative Diabetic Retinopathy (NPDR). In the current research, both eyes of 68 patients with mild or moderate NPDR, without clinically significant macular edema, were studied. Levels of fasting serum lipids, HbAlc, and CMT were measured during the first visit and at the end of the follow-up period (3 months). For statistical analysis, CMTs of each eye were studied and the correlation of changes was investigated. Additionally, the direction of changes in CMT for each eye was determined, and whether the changes in both eyes were symmetrical was investigated. Out of 68 patients, 24 were male and 44 were female. The mean CMT of all eyes was 290.05 ± 48.90 µm during the first visit and 286.80 ± 37.57 µm on the 3rd month follow-up. The mean HbAlc was 8.71 ± 1.82% at first visit to the hospital and the mean HbAlc was 8.39 ± 1.65% at the final visit. Although the changes in HbA1c and CMT during the follow-up period were statistically insignificant, the correlation of these 2 values was statistically significant (p=0.01). However, amongst l3 patients, the CMTs were asymmetrically changed in each eye during the follow-up period. To the best of the author's knowledge, this was the first study, which indicated a significant correlation in changes of CMT and HbA1c, even amongst patients with low-grade diabetic retinopathy. Demonstration of asymmetric changes in CMT of each treatment-naive eye of the same patient, during changes in systemic conditions, was another important finding of this study.

Comparing GWAS Results of Complex Traits Using Full Genetic Model and Additive Models for Revealing Genetic Architecture

Most of the genome-wide association studies (GWASs) for human complex diseases have ignored dominance, epistasis and ethnic interactions. We conducted comparative GWASs for total cholesterol using full model and additive models, which illustrate the impacts of the ignoring genetic variants on analysis results and demonstrate how genetic effects of multiple loci could differ across different ethnic groups. There were 15 quantitative trait loci with 13 individual loci and 3 pairs of epistasis loci identified by full model, whereas only 14 loci (9 common loci and 5 different loci) identified by multi-loci additive model. Again, 4 full model detected loci were not detected using multi-loci additive model. PLINK-analysis identified two loci and GCTA-analysis detected only one locus with genome-wide significance. Full model identified three previously reported genes as well as several new genes. Bioinformatics analysis showed some new genes are related with cholesterol related chemicals and/or diseases. Analyses of cholesterol data and simulation studies revealed that the full model performs were better than the additive-model performs in terms of detecting power and unbiased estimations of genetic variants of complex traits.

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.

Lower Hemoglobin Concentration Is Associated with Retinal Ischemia and the Severity of Diabetic Retinopathy in Type 2 Diabetes

Aims. To assess the association of blood oxygen-transport capacity variables with the prevalence of diabetic retinopathy (DR), retinal ischemia, and macular oedema in patients with type 2 diabetes mellitus (T2DM). Methods. Cross-sectional, case-control study (N = 312) with T2DM: 153 individuals with DR and 159 individuals with no DR. Participants were classified according to the severity of DR and the presence of retinal ischemia or macular oedema. Hematological variables were collected by standardized methods. Three logistic models were adjusted to ascertain the association between hematologic variables with the severity of DR and the presence of retinal ischemia or macular oedema. Results. Individuals with severe DR showed significantly lower hemoglobin, hematocrit, and erythrocyte levels compared with those with mild disease and in individuals with retinal ischemia and macular oedema compared with those without these disorders. Hemoglobin was the only factor that showed a significant inverse association with the severity of DR [beta-coefficient = -0.52, P value = 0.003] and retinal ischemia [beta-coefficient = -0.49, P value = 0.001]. Lower erythrocyte level showed a marginally significant association with macular oedema [beta-coefficient = -0.86, P value = 0.055]. Conclusions. In patients with DR, low blood oxygen-transport capacity was associated with more severe DR and the presence of retinal ischemia. Low hemoglobin levels may have a key role in the development and progression of DR.

Inflammation, haemostatic disturbance, and obesity: possible link to pathogenesis of diabetic retinopathy in type 2 diabetes

PURPOSE

The pathogenesis of diabetic retinopathy (DR) is insufficiently understood but may possibly involve chronic, low-grade inflammation. The aim of this cross-sectional study was to investigate the relationship between inflammatory and haemostatic markers, other markers of endothelial dysfunction and anthropometric parameters, and their association with DR in patients with type 2 diabetes.

METHODS

According to the DR status patients were divided into three groups: no retinopathy, mild/moderate nonproliferative (NPDR), and severe NPDR/proliferative retinopathy (PDR).

RESULTS

The groups did not differ in the levels of inflammatory and haemostatic markers, other markers of endothelial dysfunction, and anthropometric parameters. After dividing the patients according to the level of obesity (defined by BMI, WC, and WHR) into three groups ANOVA showed the differences in C-reactive protein according to the WC (P = 0.0265) and in fibrinogen according to the WHR (P = 0.0102) as well as in total cholesterol (P = 0.0109) and triglycerides (P = 0.0133) according to the BMI. Logistic regression analyses showed that diabetes duration and prolonged poor glycemic control are the main predictors of retinopathy in patients with type 2 diabetes.

CONCLUSION

Interrelations between obesity, inflammation, haemostatic disturbance, and other risk factors may possibly play an important additional role in endothelial dysfunction involved in the pathogenesis of diabetic retinopathy.