Prevalence of chronic kidney disease in community-dwelling elderly and associated cardiovascular risk factors

Background: Chronic kidney disease is a major public health problem in developed countries. The incidence of patients on dialysis is increasing progressively in the last years. The ageing population and increasing incidence of diabetes and hypertension are the main causes. Moreover, the level of kidney function is now recognised as a major risk factor for cardiovascular disease, even in mild cases. There is a great unaware about the prevalence of mild to moderate chronic kidney disease in the general population. The aim of the present study was to know the kidney function level in our general population over 64 years old, and the associated cardiovascular risk. Methods: This is an epidemiological descriptive cross-sectional study, obtained by a representative random sampling of the population over 64 years living in the reference area of our Hospital. The glomerular filtration rate was estimated by the Cockroft-Gault formula and the MDRD equations. Kidney function has been classified by the K/DOQI stages. We examined the univariate and multivariate association between the estimated glomerular filtration rate and the presence of cardiovascular events. Results: We analysed 253 subjects aged 65 to 93 years (mean 72 +/- 5.4). Present comorbidities were: HTA 64%, dislipemia 29%, diabetes 14%, active smokers: 10% of men, 1,5% of women. A previous cardiovascular event was present in 11% of patients (15% of men; 6,8% of women). A serum creatinin level over 1,3 and 1,5 mg/dl was present in 3,8% of women and 8% of men respectively. Nevertheless, chronic kidney insufficiency (estimated clreatinie clearance less than 60 mlx') was present in 31-49% relying on the utilised formula. In addition to age, sex, and diabetes, an independent graded association was observed between reduced glomerular filtration rate and the existence of cardiovascular events. Conclusions: We have confirmed a high prevalence of renal insufficiency among elderly people, usually not detected by the isolated plasma creatinin concentration This aspect is important for cardiovascular stratification risk and medical decisions (diagnostic and/or therapeutic). The level of glomerular filtration rate is independently associated with cardiovascular events.