Correlation of Risk Factors with Severity of Diabetic Retinopathy - A Retrospective Study.

Diabetic retinopathy (DR) is a major microvascular complication of diabetes. It is the most common cause of blindness in the working-age population in developed countries. We wanted to analyse the correlation between risk factors of blindness like duration of diabetes, dyslipidaemia, hypertension, HbA1c with severity of diabetic retinopathy in order to design appropriate strategies for prevention and treatment of diabetic retinopathy.METHODSThis was a retrospective study of all diabetic patients with diabetic retinopathy who presented to the eye OPD at KS Hegde Medical Academy from April 1st 2018 to March 31st 2019 that fulfilled the inclusion criteria. A dilated fundus examination was done to note the grade of diabetic retinopathy. The demographic data along with the duration of diabetes, HbA1c values, Cholesterol levels and Blood pressure were documented and correlated with the severity of diabetic retinopathy.RESULTSThe study included 92 patients, of which 63 were males and 29 were females with a mean age of 54.5±2.8 years. We found that there was statistically significant association between the duration of diabetes and HbA1c levels with severity of diabetic retinopathy (p= 0.022 and 0.034 association), whereas there was no statistically significant correlation between blood pressure and cholesterol levels with severity of diabetic retinopathy (p= 0.52 and 0.456 respectively)CONCLUSIONSDiabetic retinopathy showed a male preponderance, with risk factors like duration of diabetes and HbA1c levels having a significant association with the severity of diabetic retinopathy. Therefore, it is essential to have a good systemic control of diabetes with diet and suitable medications. Diabetic retinopathy is a preventable cause of blindness when diagnosed early and screening of diabetic retinopathy must be done in all diabetics to prevent the progression of the disease.

Study of Association of Serum Lipids with Diabetic Retinopathy in Type 2 Diabetes Mellitus.

The present study was conducted to find out the role of serum lipids in the development of diabetic retinopathy in type II Diabetes Mellitus. One hundred fifty subjects aged 30-70 years attending OPD at Old Civil hospital, Surat, participated in the study and were divided into three groups. Group I included 50 healthy non-diabetic subjects who served as control. Group II included 50 diabetic subjects with no signs of diabetic retinopathy and Group III included 50 diabetics with diabetic retinopathy. Funduscopy under homatropine was done in all the subjects. Serum triglycerides and total cholesterol were estimated by enzymatic methods and High Density Lipoprotein by precipitation method. Serum Low density lipoprotein was calculated using Friedewald’s formula. It was found that triglyceride levels were significantly raised (p<0.05) in subjects with diabetic retinopathy as compared to those without diabetic retinopathy showing a positive association of Triglycerides with the incidence of diabetic retinopathy. Whereas no such association was found between low density lipoprotein and total cholesterol levels with the prevalence of diabetic retinopathy.

Identification of Causal and/or Rare Genetic Variants for Complex Traits by Targeted Resequencing in Population-based Cohorts

Genome-wide association studies (GWASs) have greatly contributed to the identification of common variants responsible for numerous complex traits. There are, however, unavoidable limitations in detecting causal and/or rare variants for traits in this approach, which depends on an LD-based tagging SNP microarray chip. In an effort to detect potential casual and/or rare variants for complex traits, such as type 2 diabetes (T2D) and triglycerides (TGs), we conducted a targeted resequencing of loci identified by the Korea Association REsource (KARE) GWAS. The target regions for resequencing comprised whole exons, exon-intron boundaries, and regulatory regions of genes that appeared within 1 Mb of the GWA signal boundary. From 124 individuals selected in population-based cohorts, a total of 0.7 Mb target regions were captured by the NimbleGen sequence capture 385K array. Subsequent sequencing, carried out by the Roche 454 Genome Sequencer FLX, generated about 110,000 sequence reads per individual. Mapping of sequence reads to the human reference genome was performed using the SSAHA2 program. An average of 62.2% of total reads was mapped to targets with an average 22X-fold coverage. A total of 5,983 SNPs (average 846 SNPs per individual) were called and annotated by GATK software, with 96.5% accuracy that was estimated by comparison with Affymetrix 5.0 genotyped data in identical individuals. About 51% of total SNPs were singletons that can be considered possible rare variants in the population. Among SNPs that appeared in exons, which occupies about 20% of total SNPs, 304 nonsynonymous singletons were tested with Polyphen to predict the protein damage caused by mutation. In total, we were able to detect 9 and 6 potentially functional rare SNPs for T2D and triglycerides, respectively, evoking a further step of replication genotyping in independent populations to prove their bona fide relevance to traits.