MICROALBUMINURIA IS ASSOCIATED WITH INSULIN-RESISTANCE IN NONDIABETICSUBJECTS - THE INSULIN-RESISTANCE ATHEROSCLEROSIS STUDY

Microalbuminuria is associated with excess cardiovascular mortality in both diabetic and nondiabetic subjects. Patients with NIDDM and micro albuminuria are more insulin resistant than those without microalbumin uria, However, the relationship between insulin resistance and microal buminuria in patients with NIDDM could be due to hyperglycemia, which can cause both insulin resistance and an increase in albumin excretion rate. Little is known about microalbuminuria and insulin resistance i n nondiabetic subjects. Therefore, we examined, cross-sectionally the relationship of insulin sensitivity (S-1 x 10(-4) min(-1).mu U-1.ml(-1 )), estimated by a frequently sampled intravenous glucose tolerance te st and the minimal model and fasting plasma insulin concentration, to microalbuminuria (albumin-to-creatinine ratio greater than or equal to 2 mg/mmol) in 982 nondiabetic subjects aged 40-69 years. Altogether, 15% of the subjects had microalbuminuria, and 32% had hypertension. Su bjects with microalbuminuria had a lower degree of insulin sensitivity (means +/- SE, 1.70 +/- 0.11 vs. 2.25 +/- 0.07, P = 0.003) and higher fasting insulin concentrations (17.4 +/- 1.1 vs, 15.7 +/- 0.5 mU/l, P = 0.059) compared with subjects without microalbuminuria, In logistic regression analysis, an increasing degree of insulin sensitivity was related to a decreasing prevalence of microalbuminuria (odds ratio = 0 .86, 95% CI: 0.79-0.94, P < 0.001), Although this relationship attenua ted after adjustment for age, sex, ethnicity, hypertension, fasting gl ucose, and BMI, it still remained significant. The association between insulin sensitivity and microalbuminuria was shown not to be differen t between normotensive and hypertensive subjects. Our results suggest a relationship between insulin resistance and microalbuminuria in nond iabetic subjects that is partially dependent on blood pressure, glucos e levels, and obesity.