DETERMINANTS OF PROGRESSION OF MICROALBUMINURIA IN PATIENTS WITH NIDDM - A PROSPECTIVE-STUDY

OBJECTIVE - To assess the degree of interindividual variation in the r ate of progression of microalbuminuria and to identify determinants of progression of microalbuminuria in patients with NIDDM. RESEARCH DESI GN AND METHODS - In a prospective cohort study, 58 microalbuminuric NI DDM patients were followed for a period of at least 24 months. During this period, the level of microalbuminuria in these patients was asses sed in triplicate 24-h urine samples on at least four separate visits. All patients had stable metabolic control and controlled blood pressu re during follow-up. Microalbuminuria was defined as an albumin-to-cre atinine ratio in 24-h urine of between 3 and 30 mg/mmol. The individua l rates of progression of microalbuminuria were calculated from linear regression analysis. At baseline, the following data were collected f or all patients: age, sex, ethnicity, time since diagnosis of NIDDM, s moking habits, drug use, blood pressure, BMI, HbA(1c), serum creatinin e, cholesterol, triglyceride, and HDL cholesterol concentrations. RESU LTS - Microalbuminuria nas found to progress linearly in time. Conside rable differences in rates of progression of microalbuminuria were fou nd, the absolute yearly change in albumin-to-creatinine ratio ranging from -5.2 to 12.9 mg/mmol. In bivariate analyses, serum triglyceride c oncentration, use of ACE inhibitors, mean arterial blood pressure, HDL cholesterol, and time since diagnosis of NIDDM correlated with progre ssion of microalbuminuria (P less than or equal to 0.05). In stepwise multiple regression analysis, a high triglyceride-to-HDL cholesterol r atio at baseline (P = 0.006) and the use of ACE inhibitors (P = 0.007) were identified as the only independent predictors of progression of microalbuminuria. CONCLUSIONS - The rate of progression of microalbumi nuria in NIDDM differs considerably between subjects. Diabetic dyslipi demia (high serum triglyceride and low HDL cholesterol) is a predictor of more rapid progression of microalbuminuria in patients with well-c ontrolled blood pressure.