Albuminuria and its correlates in an Iranian type 2 diabetic population

OBJECTIVE: To study the prevalence and correlates of increased urinary albumin excretion (UAE) in an Iranian type 2 diabetic population. METHODS: Over a one year period since October 2002, 400 consecutive type 2 diabetic patients referred to an outpatient diabetes clinic, were enrolled in a cross sectional study. Subjects had no history of renal impairment or overt proteinuria. Data concerning demographic characteristics and cardiovascular risk factors were recorded and height, weight and blood pressure were measured. Glucose, cholesterol, HDL-C, LDL-C, triglyceride, apoprotein B, lipoprotein a, creatinine, and HbA1c were measured in fasting blood samples. Overnight twelve-hour UAE were assessed by immunoturbidometry method. Regression analyses were employed to determine the correlates of UAE. RESULTS: Out of 400 patients, 156 (40%) subjects had increased UAE (UAE ≥ 30 mg/24 hour). The UAE was higher in males compared to females (145.5 vs. 72.1 mg/day; p < 0.05); however, the age and HDL adjusted UAE levels were not significantly different between men and women (120.1 vs. and 87.9 mg/day; p = 0.37). Increased UAE was correlated with decreasing HDL-C and a longer duration of diabetes independent of other variables; increased UAE was correlated with HbA1c as well. Age, systolic and diastolic blood pressure, total cholesterol, LDL-C, triglyceride, apoprotein B, lipoprotein a, and GFR did not correlate with increased UAE. CONCLUSION: In this study, increased UAE was considerably frequent among type 2 diabetic patients without any significant history of renal dysfunction. Albuminuria was found to be associated with dyslipidemia (low HDL-C), long duration of diabetes, and uncontrolled glycemia revealed by higher HbA1c.