Prevalence of abnormal urinary albumin excretion in elderly people: a Spanish survey

HERMEX is a population-based study, which tries to evaluate the prevalence of cardiovascular risk factors in the population of Extremadura, Spain. This report provides the data concerning albuminuria in the elderly people recruited in the survey.

3,402 subjects were randomly selected from the database of the Health Care System of Extremadura. The final sample included 2,813 subjects (mean age 51.2 years, 53.5 % female). Urinary albumin excretion rate (UAER) in the first morning urine sample was analyzed. Albuminuria was diagnosed when UAER (albumin-to-creatinine ratio) was ≥ 22 mg/g in men or ≥ 31 mg/g in women.

The prevalence of abnormal UAER in the elderly population was 10.9 % (microalbuminuria: 8.9 %; overt proteinuria: 1.8 %). The younger subjects showed a lower prevalence of microalbuminuria (3.4 %, p < 0.001). Elderly patients showed a higher prevalence of cardiovascular risk factors than the younger ones. The elderly had higher systolic blood pressure and pulse pressure than the younger ones. Furthermore, the elderly subjects had lower plasma levels of HDL cholesterol, but higher triglycerides, glucose, creatinine, and glycosylated hemoglobin; no differences were found for total and LDL cholesterol. When the prevalence of causes of microalbuminuria was compared between age groups, we found a sharp increase in diabetic and, especially, hypertensive patients in the elderly group. The multivariate analysis showed an independent association of microalbuminuria with systolic blood pressure and plasma creatinine.

A high prevalence of abnormal UAER in elderly people was detected in a randomly selected sample of Spanish general population. In most elderly patients, microalbuminuria was associated with high blood pressure and, less frequently, with diabetes mellitus.