Metabolic Syndrome and the Risk of Chronic Renal Disease in a Hypertensive Population

Abstract

The metabolic syndrome (MS) has been related to the development of renal disease in different populations. Our aim was to study the association of MS with chronic renal disease a hypertensive population. We did the study between a population of 1231 patients attended in our Hypertension Unit with a previous diagnosis of essential hypertension we selected 581 (51.6% males), with a age of 56,8 ± 13,7 years, and basal normal renal function (estimated glomerular filtration rate [e-GFR] calculated by MDRD formula >60/ml/min/1.73m2) and without microalbuminuria (albumin/creatinine ratio <22 mg/gr males and <30 mg/gr females). MS was defined according ATP-III criteria. 310 patients (52%) accomplished for MS criteria and 17 (13%) had type 2 diabetes mellitus. Basal e-GFR was 87.6 ± 18 /ml/min./1.73m2 and basal microalbuminuria 6.5 ± 5.8 mg/gr creatinine. After 4.2 years of follow-up 102 patients (17.3%) developed microalbuminuria: 72 (12.2%) in the group with MS and 30 (5%) in the group without it. 46 patients (7%) developed chronic renal insufficiency: 27 (4, 5%) in whose with MS and 19 (3,2%) in whose without it. In the multivariate analysis the odds ratio (adjusted for age, gender, e-GFR body mass index and treatment with angiotensin system inhibitors), for the development of microalbuminuria was 2.3 (95% CI: 1.36–3.31, p = 0.001) in the group wit MS with respect to the group without it. Excluding diabetics patients this risk decreased but remain significant (OR = 1.88, 95% CI: 1.19–2.98, p = 0.005). Between the MS criteria just fasting glucose predicted the development of microalbuminuria ((OR = 1.82, 95% CI: 1.1–2.9, p = 0.012). The evolution to chronic renal insufficiency did not show differences between the two groups (OR = 1.14, 95% CI: 0.63–2.06, p = 0.66). In conlusión, in our hypertensive population the presence of MS doubled the risk for the development of microalbuminuria, even after excluding diabetics patients. However the risk of chronic renal insufficiency was not higher in the MS group, probably as a consequence of a follow-up period too short in relation to a well preserved basal renal function.