Atherosclerosis profile and microalbuminuria in essential hypertension

Whether microalbuminuria (MA) is the result of intrarenal hemodynamic changes induced by increased systemic blood pressure (BP) or a marker of capillary leakiness at the glomerular level that reflects more generalized atherosclerotic vascular damage is still debated. To address this question, 319 patients without diabetes, 154 men and 165 women aged 57 +/- 8.6 years (range, 37 to 73 years), but with essential hypertension (EH) never treated with drugs were enrolled onto the study. Using a multiple linear regression analysis, we analyzed the prevalence of MA and its relationship with BP level as well as with other risk factors for the development of atherosclerosis. MA was present in 40% of the population studied. A univariable analysis of ambulatory BP monitoring measurements showed that only 24-hour systolic BP (P = 0.04), daytime systolic BP (P = 0. 02), and 24-hour daytime and nighttime systolic BP load (P < 0.01) predicted the presence of MA, whereas all BP variability parameters significantly predicted it. Multivariable analysis showed that only a positive family history of hypertension (P < 0.001), BMI (P < 0. 001), glucose (P < 0.001), and 24-hour systolic BP coefficient of variation (P < 0.001) independently predicted MA. In summary, the prevalence of MA in our group of patients with EH was high, presumably as a consequence of the older mean age of the population and the selection criteria. Besides being a marker of concomitant cardiovascular damage, MA was associated with a worse pattern of atherosclerotic risk factors. Although its pathophysiological meaning remains to be completely clarified, MA seems to be more related to other atherosclerosis risk factors and presumably reflects a more diffuse vascular injury.