[Risk factors for the development of persistent proteinuria in patients with type 2 diabetes mellitus].

BACKGROUND The natural history of diabetic nephropathy is well defined in type 1 diabetes, but to a lesser degree in type 2 diabetes, possibly due to diversity of involved risk-factors. The main aim of the study was to assess modifiable and nonmodifiable risk-factors in the development of persistent proteinuria in patients with type 2 diabetes mellitus. METHODS A random sample of 90 diabetic patients, regularly checked up at the Department of Endocrinology, was selected and followed up in a period of 5 years. There were 46 males and 44 females, aged 51.8 +/- 9.9 years, with average duration of disease of 6.8 +/- 5.2 years, including 58 (64.4%) hypertensive patients and 58 (64.4%) smokers. All the participants had fasting and postprandial glycaemia, Hbalc, 24/hour proteinuria and blood pressure measured. Only 4 (4.4%) persons had 24/h proteinuria > 200 mg/d at the beginning of the study. RESULTS In a 5 year period, 21 (23.3%) patient developed proteinuria of > 200 mg/d. The main prognostic factors were Hbalc values (RR 3.5, p = 0.03), duration of the disease (RR 3.1, p = 0.02), hypertension (RR 2.9, p = 0.02), with stronger impact of diastolic than systolic values (RR 2.01 vs RR 1.83), age (RR 1.35, p = 0.02), glycaemia with stronger correlation of postprandial than fasting values (RR 1.52 vs 1.34), smoking (RR 1.26, p = 0.06) while sex and BMI values were not strongly associated with the development of the proteinuria (RR 1.09 and RR 1.01 respectively). CONCLUSIONS Results indicate that, in addition to glycemic control, control of additional modifiable risk-factors, particularly hypertension and smoking, is of utmost importance in the treatment of patients with type 2 diabetes mellitus.