Microalbuminuria, insulin sensitivity and haemostatic factors in non-diabetic treated hypertensive men. Risk Factor Intervention Study Group.

Abstract

To examine whether microalbuminuria in non-diabetic, treated hypertensive men is associated with insulin resistance and measures of endothelial function, thrombogenesis and fibrinolysis. Cross-sectional study. Outpatient clinic in city hospital. Ninety-two treated hypertensive men, aged 57-77 years, either with a serum cholesterol of > or = 6.5 mmol L-1 or smokers, or both. Patients with diabetes mellitus or overnight urinary albumin excretion of > 100 mg 12 h-1 were excluded. Overnight urinary albumin excretion, insulin-mediated glucose disposal (hyperinsulinaemic euglycaemic clamp), blood glucose and plasma insulin during oral glucose tolerance test, fibrinogen, von Willebrand factor and plasminogen activator inhibitor activity. Microalbuminuric patients had increased blood glucose concentrations during the oral glucose tolerance test and higher plasma fibrinogen levels compared with the normoalbuminuric patients. In a randomly selected subgroup (n = 36), insulin-mediated glucose disposal was lower in microalbuminuric than in normoalbuminuric patients, and an inverse relationship between insulin sensitivity and albuminuria (r = -0.37; P = 0.028) was found. This relationship was not significant after adjustment for body-mass index (P = 0.098). In the univariate analyses including all patients, albuminuria was associated with blood glucose, serum creatinine, body-mass index, systolic blood pressure, fibrinogen, von Willebrand factor and cholesterol (negatively). In a multiple regression analysis, only the body-mass index was independently related to urinary albumin excretion. Microalbuminuria was associated with insulin resistance but obesity was a confounding factor. Relationships between microalbuminuria and fibrinogen as well as von Willebrand factor were found, but only in univariate analysis.