Purpose
To determine the social, lifestyle, clinical and genetic risk factors in the Mumbai urban slum population. Prevalence of DR in T2DM varies from 4-52% and is between 12-26% for Asian Indians. Several social (urbanisation, disparity in healthcare access), lifestyle (abdominal obesity, cultural dietary practices), anthropometric (truncal obesity, waist:hip ratio, BMI) clinical (age, duration of DR, insulin resistance, insulin treatment, hyperglycaemia, glycemic control, hypertension, hyperlipidemia, anaemia, sight threatening DR, macular oedema) and genetic/epigenetic (family history, over 60 associated DR genes like ALR, VEGF, ACE, RAGE, PKC, NOS) risk factors are associated with DR. Prevalence of DR in newly diagnosed DM is low, 5-7% compared to Nepal (19.35%), Sri Lanka and Pakistan (15% each).
Methods
Aditya Jyot Diabetic Retinopathy in Urban Mumbai Slums Study, an ongoing population based cross-sectional study, wherein eligible subjects aged 40 years or above are screened for DR and profiled for demographic, biosocial and biochemical parameters to study the association of these factors with DR. The data collection included socio-economic, lifestyle based questionnaire; family and medical histories, anthropometric measurements and a routine/thorough ophthalmic examination and in particular retinal evaluation, including fundus photography. Biochemical tests included haemoglobin, glycosylated haemoglobin and microalbuminuria. We would be assessing the genetic risk factors at a later phase of the study.
Results
Four hundred and seventy subjects with T2DM were analyzed in the present study. The median age of subjects without DR was 55.76 + 9.13 and with DR was 55.74 + 9.55. Of these 321 (85.9%) subjects were known diabetics (KD) and 64 (14.1%) were newly detected diabetics (NDD). Positive correlation was also observed for increased duration of DM (> 15 yrs) and increasing age in subjects with DR (p=0.000003). Male sex was observed to be strongly associated with the presence of DR (p=0.0048).
Conclusions
Positive association was shown in the study for (i) male gender, (ii) longer duration of DM and higher age group. DR being a complex disease, the combination of lifestyle, social, demographic, genetic and epigenetic factors should influence the onset and progression of DR.