HIGH PREVALENCE OF DIABETIC-RETINOPATHY AND NEPHROPATHY IN POLYNESIANS OF WESTERN-SAMOA

OBJECTIVE - To determine the prevalence of diabetic retinopathy and ne phropathy and to define associated risk factors in Polynesian Western Samoans with non-insulin-dependent diabetes mellitus (NIDDM) or impair ed glucose tolerance (IGT). RESEARCH DESIGN AND METHODS - A 1991 popul ation-based study in Samoan adults (ages 25-74 years) included a 75-g oral glucose tolerance lest, anthropometric measurements, and blood pr essure recordings. Subjects with NIDDM or IGT had 45-degree stereo pho tographs taken (n = 263) (three standard fields of the right eye), and retinopathy was graded in comparison with Airlie House photographs. F irst-morning urine samples (n = 304) were also collected from these su bjects and from a subsample with normal glucose tolerance. Urinary alb umin concentration (UAC) was measured by radio-immunoassay: microalbum inuria was defined as UAC of 30-299 mu g/ml; and macroalbuminuria was defined as UAC greater than or equal to 300 mu g/ml. RESULTS - The pre valence of diabetic retinopathy was 43.2% among subjects with known di abetes and 15.4% in those newly diagnosed. Proliferative diabetic reti nopathy was found in 4.5% of known diabetic subjects. The prevalence o f elevated UAC was 15.0% in subjects with IGT, 26.0% in newly diagnose d diabetes subjects, and 23.4% in known diabetes subjects. For all dia betic subjects (n = 162), the factors independently associated with di abetic retinopathy (logistic regression) were duration of diabetes, fa sting plasma glucose, and body mass index (inversely). Duration of dia betes, serum triglyceride concentrations, and systolic blood pressure were independently associated with elevated UAC in all diabetic subjec ts (n = 138), and lasting plasma glucose had borderline significance. CONCLUSIONS - Diabetic retinopathy and albuminuria are common in Polyn esian Western Samoans. Duration of diabetes and level of glycemia were the most important associated factors. These data underline the need for cost-effective programs for the detection and early treatment of d iabetes in Western Samoa and other developing populations with high su sceptibility to NIDDM.