BACKGROUND
Microalbuminuria is associated with increased cardiovascular mortality in type 2 diabetic patients and non-diabetic subjects. This study was undertaken to determine the prevalence ot microalbuminuria among diabetic and non-diabetic subjects in Korea and to determine the factors associated with microalbuminuria. METHOD: A sample of 1,791 subjects aged > 40 years living in Jungup district were selected from the 28,380 inhabitants using a random cluster sampling method. Among these subjects, 1,006 of them (56.1%) underwent the 75 g oral glucose tolerance test that was also part of the timed overnight urine collection. 46 subjects were excluded because they had signs of urinary tract infection (n=41) or overt proteinuria (n=5). Microalbuminuria was defined as urinary albumin excretion rate (UAER) between 20 and 200 pg/min. RESULTS: Subjects with microalbuminuria had a higher weight and body mass index (BMI), abdominal circumference, systolic and diastolic blood pressure (BP), fasting and 2hr plasma glucose, fasting semm insulin and proinsulin concentrations than subjects without microalbuminuria. The prevalence of micro- albuminuria increased as the glucose tolerance worsened[6.0% in normal glucose tolerance, 11.8% in impaired glucose tolerance (IGT) and 21.8% in diabetes, respectively; x trend=25.9, p<0.(0001]. Mean UAER of subjects with hypertension was greater than that of subjects without hypertension (7.8+0.9ug/min vs. 9.6+0.7ug/min, p<0.001). Univariate analysis revealed that the UAER was significantly (p<0.05) correlated with weight and BMI, abdominal circumference, systolic and diastolic BP, fasting and 2hr plasma glucose, fasting serum insulin and proinsulin after sex-adjustment. Multiple regression analysis revealed that weight or BMI, diastolic BP, 2hr plasma glucose and fasting serum insulin were independently associated with UAER in non-diabetic subjects. CONCLUSION: The present study demonstrates that the prevalence of microalburninuria is higher in patients with glucose intolerance. The association of the UAER with BMI, diastolic BP, 2hr plasma glucose and fasting serum insulin suggest that microalbuminuria is a feature of the insulin resistance syndrome.