Microalbuminuria, a parameter independent of metabolic influences in hypertensive men

Objective To evaluate the relationship of albuminuria and microalbuminuria (overnight urine albumin greater than or equal to 15 mug/min) with insulin resistance and related metabolic abnormalities in patients with essential hypertension. Design Cross-sectional evaluation of 271 (age range, 19-77 years) never-treated, non-diabetic, uncomplicated hypertensive men. Main outcome measures Triplicate overnight urine albumin determination and homeostasis model assessment (HOMA) of insulin resistance as a surrogate measure of insulin sensitivity. Additional parameters were fasting and post-load circulating glucose and insulin, lipids, body mass index, blood pressure and echocardiographic left ventricular mass. Results HOMA, fasting and post-challenge glucose and insulin, percentages of glucose-intolerant patients, triglycerides and high-density lipoprotein cholesterol levels did not differ across ascending urine albumin quartiles. Body mass index, blood pressure and ventricular mass were significantly greater in the upper quartiles, and the prevalence of obesity fivefold more frequent in the top as compared with the bottom urine albumin fourth. The statistical trend was unchanged after adjustment for HOMA, while accounting for systolic blood pressure and left ventricular mass by co-variance analysis abolished it. Eighty-eight patients bearing the phenotypic traits of the metabolic syndrome and a striking degree of insulin resistance and hyperinsulinemia showed urine albumin rates and prevalence of microalbuminuria comparable with the 183 patients who were not affected by that syndrome. Conclusions Albuminuria is independent of insulin resistance and other phenotypic components of the metabolic syndrome in never-treated, non-diabetic essential hypertensive men. Microalbuminuria is more frequent in obese hypertensives but this association is explained by higher blood pressure more than insulin resistance.