What is the evidence that microalbuminuria is a predictor of cardiovascular disease events?

Abstract

This review describes recently published studies evaluating the association between microalbuminuria and the development of cardiovascular disease events either in the presence of diabetes or hypertension, or in the population as a whole. Prospective studies confirm that microalbuminuria is predictive, independently of classical risk factors, of cardiovascular disease events and all-cause mortality within groups of patients with diabetes or hypertension and in the general population. However, these studies suggest that levels of albuminuria below the conventional cutoff point definition of microalbuminuria are significantly associated with cardiovascular morbidity and mortality. The pathophysiological mechanism underyling this association is still uncertain. Data from recent intervention studies suggest that treatment with angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers, as well as intensive multi-factorial intervention including behaviour modification and targeted pharmacotherapy in patients with microalbuminuria, offers significant reduction in cardiovascular and renal morbidity in people with albuminuria. Future absolute risk prediction scores for primary cardiovascular events could include microalbuminuria as a modifiable risk factor. The association between levels of albuminuria and cardiovascular outcomes in individuals within the normoalbuminuric range questions the current categorical definition of microalbuminuria. Intensive multifactorial interventions, including the use of agents that affect the renin-angiotensin pathway, are effective in reducing cardiovascular risk in patients with microalbuminuria and diabetes or hypertension.