Abstract
Purpose:
Low levels of 25-hydroxyvitamine D (Vit D) have been implicated in diabetes and its microvascular complications, including diabetic retinopathy (DR). However, data from Asian populations are lacking. In the current study we examined the association between 25-Vit D and DR in a multi-ethnic Asian population.
Methods:
A nested case-control design study was conducted using data from three population-based cohorts: Singapore Chinese Eye Study (SCES), Singapore Malay Eye Study (SiMES) and Singapore Indian Eye Study (SINDI). All subjects underwent a comprehensive eye examination including retinal photography, and blood samples were collected. Diabetes was defined as casual plasma glucose ≥200mg/dl (11.1mmol/l), glycosylated hemoglobin (HbA1c) levels ≥6.5%, self-reported physician-diagnosed diabetes, or the use of glucose lowering medication. Retinal photographs, taken from both eyes, were graded for the presence and severity of DR using the modified Airlie House classification system. A total of 695 controls (persons with diabetes, but without DR) and 328 cases (patients with DR) were selected for the present analyses. Serum levels of 25-Vit D and parathyroid hormone were measured using samples stored at baseline.
Results:
The mean age of this sample was 67.8 years (standard deviation: 8.1), of whom 47.3% were women. The mean serum levels of 25-Vit D were 20.0ug/l in the cases and 21.7ug/l in the controls (unadjusted p-value = 0.02). However, in multivariate logistic regression models adjusted for age, sex, body mass index, blood pressure, duration of diabetes and parathyroid hormone levels, 25-Vit D levels were not associated with the presence of DR [odds ratio: 0.97; 95% confidence interval: 0.82-1.14].
Conclusions:
In the current study, levels of 25-hydroxy-vitamine D were not associated with the presence of DR in a multi-ethnic Asian population.
Keywords: 464 clinical (human) or epidemiologic studies: risk factor assessment •
499 diabetic retinopathy