Background and objectives: Epidemiological data on the incidence and prevalenc e of cardiovascular disease in chronic renal failure are scant. The objective of the present study is to assess the relationship between renal function, measure d by the estimated glomerular filtration rate, and the presence of early or esta blished cardiovascular disease, in a population of hypertensives from primary ca re. Patients and methods: Cross-sectional, multicentre study carried out in primary care c entres all over Spain. Hypertensive subjects, older than 55 years, were included . In all of them a structured interview including cardiovascular risk factors or disease was performed. Blood pressure was measured following a standard procedu re, and serum biochemistry and an electrocardiogram were obtained. Renal functio n was estimated using the abbreviated MDRD(Modification of Diet in Renal Disease Study Group) equation. For each glomerular filtration rate stratum the odds rat io and 95%confidence interval(CI) of left ventricular hypertrophy or cardiovasc ular disease were calculated, adjusted by confounding variables. Results: A tota l of 13 687 patients(mean age 68.1 years, women 55.4%, diabetics 30.6%, body m ass index 28.6 kg/m2) were included. Of these, 26.4%had established cardiovascu lar diseases and 20.3%electrocardiographic left ventricular hypertrophy. The av erage serum creatinine was 1.01 mg/dl, creatinine clearance 70.0 ml/min, and glo merular filtration rate 74.0 ml/min per 1.73 m2. Thirty-three patients(0.24%) had glomerular filtration rate< 5 ml/min per 1.73 m2; 89(0.65%) from 15 to 29; 3745(27.36%) from 30 to 59; 7798(56.97%) from 60 to 89; and 2019(14.75%) high er than 89 ml/min per 1.73 m2. In a multiple regression analysis, after adjustin g by age, sex, body mass index, diabetes, systolic and diastolic blood pressure, and smoking, a lower glomerular filtration rate was associated with a higher pr evalence of left ventricular hypertrophy. Likewise, a reduction in the glomerula r filtration rate was also associated with a higher prevalence of cardiovascular disease. Conclusions: In hypertensive patients from primary care, the prevalenc e of cardiovascular disease is inversely proportional to the level of renal func tion. Estimated glomerular filtration is easy to determine and complements evalu ation of the hypertensive patient. Background and Objectives: Epidemiological data on the incidence and prevalence of cardiovascular disease in chronic renal failure are scant. The objective of the present study is to assess the relationship between renal function, measure d by the estimated glomerular filtration rate, and the presence of early or esta blished cardiovascular disease, in a population of hypertensives from primary ca re. Patients and methods: Cross-sectional, multicentre study carrying out in primary care c entres all over Spain. Hypertensive subjects, older than 55 years, were included. In all of them a structured interview including cardiovascular risk factors or disease was performed. Blood pressure was measured following a standard procedu re, and serum biochemistry and an electrocardiogram were obtained. Renal functio n was estimated using the abbreviated MDRD (Modification of Diet in Renal Disease Study Group) equation. For each glomerular filtration rate stratum the odds rat io and 95% confidence in Results: A tota l of 13 687 patients (mean age 68.1 years, women 55.4%, diabetics 30.6%, body m ass index 28.6 kg / m2) were included. 26.4% had established cardiovascu-lar diseases and 20.3% electrocardiographic left ventricular hypertrophy. The av erage serum creatinine was 1.01 mg / dl, creatinine clearance 70.0 ml / min and glomalular filtration rate 74.0 ml / min per 1.73 m2 Thirty-three patients (0.24%) had glomerular filtration rate <5 ml / min per 1.73 m2; 89 (0.65%) from 15 to 29; 3745 (27.36%) from 30 to 59; from 60 to 89; and 2019 (14.75%) high er than 89 ml / min per 1.73 m2. In a multiple regression analysis, after adjustin g by age, sex, body mass index, diabetes, systolic and diastolic blood pressure, and smoking , a lower glomerular filtration rate was associated with a higher pr evalence of left ventricular hypertrophyn the glomerula r filtration rate was also associated with a higher prevalence of cardiovascular disease. Conclusions: In hypertensive patients from primary care, the prevalenc e of cardiovascular disease is inversely proportional to the level of renal func tion. and complements evalution of the hypertensive patient.