Progression to overt proteinuria in microalbuminuric Koreans with non-insulin-dependent diabetes mellitus

Long-term data concerning the progression of microalbuminuria are not avail able in Koreans with non-insulin-dependent diabetes mellitus (NIDDM). To el ucidate potential risk factors of the development of overt proteinuria in m icroalbuminuric Koreans with NIDDM, we studied retrospectively 46 patients with NIDDM. Between 1989 and 1990, they were found to have persistent micro albuminuria, and then were followed up regularly. Urinary albumin excretion rates (UAEs) were measured on a 24-h urine sample. Microalbuminuria was de fined as UAE between 20 and 200 mu g/min, and overt proteinuria as UAE > 20 0 mu g/min on two consecutive occasions. After a mean of 4.5 years (range 3 -6), 23 patients progressed to overt proteinuria (progressors), and others remained microalbuminuric (nonprogressors). Duration of diabetes was signif icantly longer in progressors than in nonprogressors. Mean fasting plasma g lucose and HbA(1c) levels during the follow-up were significantly higher in progressors compared with nonprogressors (11.5 +/- 3.6 vs. 8.7 +/- 2.5 mmo l/l, P = 0.006, and 8.9 +/- 1.5 vs. 7.5 +/- 1.4%, P = 0.005, respectively). In addition, frequencies of overt proteinuria were significantly higher in patients with their mean HbA(1c) > 8% during follow-up than in patients wi th their mean HbA(1c) less than or equal to 8% during follow-up (65.2 vs. 3 0.4%, P = 0.015). Mean systolic blood pressure and mean diastolic blood pre ssure during follow-up tended to be higher in progressors compared with non progressors. Multiple logistic regression analysis revealed that mean HbA(1 c) levels and mean systolic blood pressure during the follow-up were the mo st significant predictors for the incidence of overt proteinuria at 4.5-yea r follow-up, when adjusted for various factors (P = 0.023, P = 0.038, respe ctively). We conclude that poor glycemic control, along with elevated systo lic blood pressure, were powerful predictors for the development of overt p roteinuria in microalbuminuric Koreans with NIDDM. (C) 1998 Elsevier Scienc e Ireland Ltd. All rights reserved.