Microalbuminuria in subjects with no history of diabetes mellitus and hypertension: the relationship with hyperglycemia and high blood pressure at non-diagnostic level.

1969 subjects underwent albumin index [A.I., urine microalbumin (mg/liter)/creatinine (g/liter)] in early morning urine, 75 g oral glucose tolerance test (OGTT), determination of plasma lipids (total cholesterol, triglyceride and high density lipoprotein-cholesterol) and a resting electrocardiogram. There was no history of treatment for diabetes mellitus and hypertension. The relationship between microalbuminuria, and hyperglycemia or high blood pressure at non-diagnostic level was examined. Then, plasma lipid levels or changes in electrocardiogram were correlated with the degree of microalbuminuria. Subjects were divided into 4 groups according to 75 gOGTT and into 3 groups according to blood pressure based on WHO definition, and A.I. was divided into 4 categories (0-9.9, 10.0-19.9, 20.0-49.9, and 50.0-199.9 mg/gCr). Mildly or moderately enhanced microalbuminuria (A.I.) was found in subjects with hyperglycemia or high blood pressure at non-diagnostic level. In normotensive subjects, neither hyperglycemia in fasting nor after glucose challenge increased urine microalbumin above normal range, while in borderline hypertensives, diabetic glucose intolerance produced 2 and 3 fold increases respectively compared with normotensives. There was a linear increase in urine microalbumin in relation to the glucose intolerance in newly diagnosed hypertensives. No correlation could be found between microalbuminuria and plasma lipid levels, while the prevalence of electrocardiographic changes increased 3 folds in group with the heaviest microalbuminuria compared with the other 3 groups excreting less microalbumin.