Albuminuria and its associated biomedical factors among indigenous adults in Far North Queensland: a 7-year follow up study

Background: To document albuminuria prevalence and its associated factors in Aboriginal and Torres Strait Islander (TSI) adults with high renal and metabolic risks from 19 rural and remote north Queensland communities. Methods: One thousand nine hundred seventy-one indigenous adults were enrolled in 1998 and 566 completed follow up in 2007 in this population-based study. Measurements included weight, waist circumference (WC), blood pressure (BP), fasting glucose, lipids, gamma-glutamyltransferase (GGT), urinary albumin creatinine ratio (UACR), smoking, alcohol intake and physical activity (PA). Albuminuria was defined as an UACR >=2.5 g/mol in males and >= 3.5 g/mol in females. The association between albuminuria and biomedical factors was assessed with generalised linear modelling. Results: Baseline albuminuria prevalence was 19.7 % (95 % CI: 18.0-21.6 %). Follow up prevalence was 42.4 % (95 % CI: 38.4-46.5 %) among the 566 adults having the 2nd UACR measurements. Follow-up albuminuria was associated with fasting glucose of 5.4 mmol/L (OR 2.5, 95 % CI 1.5-4.2), GGT tertiles in a dose-response manner (OR 2.0 for 2nd and 3.7 for 3rd tertile, p for trend <0.001), and abdominal overweight and obesity (OR 2.1, 95 % CI 1.1-3.9 and 5.4, 95 % CI: 2.2-13.5 respectively). Aboriginal people with diabetes were three times more likely of having albuminuria compared to TSI counterparts, while TSI smokers had twice the likelihood (95 % CI 1.2-3.2). At both baseline and follow up, albuminuria was more prevalent among older participants. Conclusions: Indigenous Australians in north Queensland are at high risk of albuminuria. Overweight and obesity, glycaemia, increased GGT, and smoking were associated with albuminuria at baseline and/or follow up.