[The value of Cockcroft-Gault equation for the screening of decreased renal function in patients with systemic arterial hypertension]. / Valor da equação Cockcroft-Gault na triagem de função renal reduzida em pacientes com hipertensão arterial sistêmica.

ABSTRACT

INTRODUCTION: Arterial hypertension is a worldwide public health problem and one of the major risk factors for chronic kidney disease development. METHODS: In order to compare the Cockcroft-Gault (CG) equation with serum creatinine and 24-hour creatinine clearance (CrCl) for the screening of reduced renal function, a cross-sectional study of 198 hypertensive patients was undertaken at a basic health unit. The demographic, nutritional, and clinical laboratory data were analyzed. Renal function was assessed by serum creatinine and 24hour CrCl. Glomerular filtration rate (GFR) was also estimated according to Cockcroft-Gault equation. RESULTS: The patients had a mean age of 60.6 ± 11.6 years-old, and 73.7% were female. The prevalence of serum creatinine > 1.2 mg/dL was 7.6% and the prevalence of GFR < 60 mL/minute was 24.2%, when evaluated by the CrCl and CG equation. Reduced GFR was observed in older male patients, with lower body mass index, normal values of fasting blood glucose, and higher levels of serum uric acid and of systolic blood pressure. DISCUSSION: The prevalence of decreased renal function among hypertensive patients varies considerably, depending on the laboratory investigation used. CG-estimated CrCl has shown to be more accurate than serum creatinine for assessing GFR. CONCLUSIONS: CG-estimated CrCl was highly similar to 24-hour CrCl, proving to be a reliable primary care screening test for the early diagnosis of renal impairment in hypertensives.