Association of microalbuminuria with carotid intima-media thickness and coronary artery disease--a cross-sectional study in Western India

Microalbuminuria, a slightly elevated albumin excretion in the urine, is considered a novel atherosclerotic risk factor, both in diabetics subjects and in general population. Carotid intima-media thickness assessed non-invasively by a B-mode ultrasound has been recently shown to be an early marker for atherosclerosis. This study aims at determining the role of microalbuminuria as an atherosclerotic risk factor and its association with coronary artery disease. We measured the urine microalbumin excretion and carotid intima-media thickness (IMT) in 301 subjects, with or without evidence for coronary artery disease (CAD). Microalbuminuria was diagnosed if urinary excretion of albumin exceeded 20 microgm/ml. Of the 301 subjects (age group--30-80 years) recruited for the study, 194 were males, 107 females. One hundred amd eighteen subjects had evidence of CAD as diagnosed by documented hospitalization with myocardial infarction or acute coronary syndrome, coronary angiography when feasible or non-invasive cardiac evaluation. One hundred and sixty three subjects had diabetes mellitus. Microalbuminuria was detected in 74 subjects (24.6%). Prevalence of subjects with increased IMT was higher among subjects with microalbuminuria compared to normoalbuminuria (42% vs 21.4%, p < 0.003). Prevalence of CAD was significantly higher among diabetic subjects with microalbuminuria compared to those with normoalbuminuria (Diabetic subjects: 58% vs 31.9%, p = 0.002, Non-diabetic subjects: 41.7% vs 37.7%, p = 0.718). Multivariate logistic regression analysis using carotid intimal medial thickness as a dependent variable revealed a statistically significant association with microalbuminuria in diabetic subjects (p = 0.027). We conclude that microalbuminuria shows a strong association with increased carotid intimal medial thickening and coronary artery disease in diabetic subjects in this Western Indian population.