Microalbuminuria as a predictive factor for cardiovascular events.

We tested the hypothesis that microalbuminuria screening in a general practice setting would identify high-risk nondiabetic hypertensive patients, and we measured microalbuminuria response to drug treatment. General practitioners were enrolled who had collected medical histories and performed physical examinations and routine laboratory tests in more than 11,000 untreated hypertensive, nondiabetic patients. Microalbuminuria was measured with an albumin-sensitive immunoassay test strip. The patients' mean age was 57 years, 51% were men, and mean duration of hypertension was 69 months. Twenty-five percent of patients had coronary artery disease (CAD), 17% had left ventricular hypertrophy (LVH), 5% had had a stroke, and 6% had peripheral vascular disease (PVD). Microalbuminuria was present in 32% of men and 28% of women. In patients with microalbuminuria, 31% had CAD, 24% had LVH, 6% had had a stroke, and 7% had PVD. In patients without microalbuminuria, all of these rates were significantly lower: 22%, 14%, 4%, and 5%, respectively (p < 0.001). Furthermore, in patients with CAD, LVH, stroke, or PVD, microalbuminuria was significantly greater than in patients who did not have these complications (p < 0.001). A multiple stepwise regression analysis with microalbuminuria as the dependent variable showed microalbuminuria depended on the following factors, in order of importance: systolic blood pressure, retinopathy, CAD, diastolic blood pressure, and LVH (all p < 0.0001). A multiple stepwise regression analysis with each of the concomitant diseases as the dependent variable showed that microalbuminuria was an independent and significant variable for each of the conditions. The patients were assigned to monotherapy with either angiotensin-converting enzyme (ACE) inhibitors, beta-blockers, calcium antagonists, or diuretics. All of the drugs reduced microalbuminuria, although the beta-blocker carvedilol was superior (p < 0.05). We concluded microalbuminuria is an important risk factor that can be influenced by treatment.