Risk Factors for Development of Microalbuminuria in Diabetic and Nondiabetic Normoalbuminuric Hypertensives with High or Very High Cardiovascular Risk – A Twelve-Month Follow-Up Study

Abstract

Aims: To investigate risk factors for progression to microalbuminuria in normoalbuminuric hypertensive patients. Methods: In a longitudinal study, 173 previously treated normoalbuminuric hypertensive patients with high cardiovascular risk (70% diabetics) were evaluated at study entry and after 12 months. Levels of urinary albumin excretion (UAE; study entry and end of study) were compared between patients remaining normoalbuminuric (RNA) and progressors to non-normoalbuminuric (NNA) levels. Results: Out of 173 patients (59 ± 13 years), 12% evolved to NNA levels. At baseline, NNA and RNA groups did not differ in age, sex, diabetes, lipids, blood pressure (BP), drug therapy, or glomerular filtration rate. In comparison with RNA patients, the NNA group showed higher hypertension duration, greater UAE and percentage of patients with UAE ≥10 mg/g creatinine (76.2 vs. 45.4%) at study entry and higher BP levels (158/92 ± 25/10 vs. 143/83 ± 20/12 mm Hg) at study end (all p < 0.05). Logistic regression analysis identified absolute UAE values at study entry and study end variation of BP and cholesterol as independent contributors to the increase in the log odds of developing microalbuminuria. Conclusions: Normoalbuminuric hypertensives with UAE within the upper two thirds of normal range are 3 times as likely to develop microalbuminuria after 1 year. A poor BP and lipid control are also associated with increased risk of microalbuminuria.