Background and objective: The objectives of this study were to describe the prevalence of subclinical renal dysfunction, assessed by glomerular filtration rate (GFR), and identify the associated cardiovascular risk factors in active working subjects of Spain.
Subjects and method: Data were collected in 11,582 active healthy workers (78.5% males), mean age (standard deviation) 40.2 (10.7) years, in their annual health examinations. Renal function was assessed by the GFR estimated by 3 methods: the abbreviated equation of Modification of Diet in Renal Disease (MDRD) study, the Cockroft-Gault (CG) equation and the weight/creatinine ratio. The assessment of the metabolic syndrome was done according to the modified Adult Treatment Panel III criteria.
Results: The 3 equations used for the estimation of GFR showed different values. GFR mean values were highest with the CG method (99.0 [25.0]) ml/min/1.73 m2, followed by the results of the MDRD and weigh/creatinine ratio (90.2 [18.5] ml/min/1.73 m2 and 81.2 [18.3] ml/min/1.73 m2, respectively). The prevalence of mild renal dysfunction (GFR: 60-89 ml/min/1.73 m2) ranged between 35.7% and 50.8% depending on the method applied, and the presence of moderate-severe (GFR < 60 ml/min/1.73 m2) ranged between 1.2% and 2.6%. All cardiovascular risk factors were more prevalent in the categories of worst renal function. Multivariant regression analysis showed that hypertriglyceridemia (odds ratio [OR] = 1.2), metabolic syndrome (OR = 1.2), overweight (OR = 1.2) and hypercholesterolemia (OR = 1.5) were associated independently with mild renal dysfunction. Hypercholesterolemia (OR = 1.6), hypertension (OR = 1.6), low HDL (OR = 2.4), and diabetes mellitus (OR = 3.2) were associated with moderate-severe renal dysfunction.
Conclusions: Renal subclinical dysfunction is highly prevalent and is independently associated with classical cardiovascular risk factors and metabolic syndrome.