Microalbuminuria in patients with Type 2 diabetes mellitus from general practice: course and predictive value

Aims To assess the course of microalbuminuria in patients with Type 2 diabe tes mellitus in general practice and the predictive value of urinary albumi n concentration on all-cause mortality, cardiovascular mortality and cardio vascular morbidity. Methods Cohort study in Type 2 diabetic patients tested for microalbuminuri a in 1992, and re-tested in 1998. During follow-up all cardiovascular morbi dity and mortality were recorded. Results Of the original sample of 317 patients, 163 patients were re-tested . The mean change in urinary albumin concentration was +16.2 mg/l (range -1 22.0 to +602 mg/l). Seventy-five per cent of the patients without microalbu minuria in 1992 still had no microalbuminuria in 1998 and 40% of those with microalbuminuria in 1992 reverted to normoalbuminuria in 1998. Cox surviva l analysis, stratified for age, showed that microalbuminuria at baseline re sulted in a risk ratio of all-cause mortality of 1.4 (95% confidence interv al 0.8-2.7), of cardiovascular mortality of 1.2 (0.5-2.8) and of new cardio vascular events (including cardiovascular mortality) of 1.4 (0.8-2.3). Conclusions In the majority of patients the change of urinary albumin excre tion was small, but the range was wide. A weak non-significant relationship between microalbuminuria and all-cause mortality and cardiovascular morbid ity was observed.