[Prevalence and clinical characteristics of microalbuminuria in the Spanish hypertensive population].

Background And Objective: The presence of microalbuminuria (MAB) in hypertension is now considered a sign of target organ damage. The aim of this study was to determine the prevalence of MAB in the Spanish hypertensive population and to correlate the degree of urinary albumin excretion (UAE) with the severity of blood pressure (BP) elevation and the presence of other cardiovascular risk factors.

Patients And Method: Cross-sectional study of 4,952 hypertensive patients attended in primary care centres. UAE was determined in a fresh urine sample by calculating the ratio of albumin to creatinine excretion (mg/g).

Results: Median UAE was 13 mg/g (interquartile range, 4-29). The prevalence of MAB considered as a UAE between 30 and 300 mg/g was 21.4% with an additional 1.8% of patients having overt proteinuria (UAE > 300 mg/g). Compared with hypertensives without MAB, those who presented this feature exhibited significantly higher (p < 0,001) systolic and diastolic BP (146/85 vs 142/83 mmHg). The prevalence of MAB was also significantly higher (p < 0.001) in patients with other cardiovascular risk factors, such as hypercholesterolemia, smoking or a family history of early cardiovascular disease, and in those exhibiting other signs of target organ damage, such as left ventricular hypertrophy or mild renal insufficiency.

Conclusions: MAB is present in more than 20% of the hypertensive Spanish population attended in primary care centres. There is a clear correlation between MAB and both BP elevation and the presence of other cardiovascular risk factors and signs of target organ damage.