Prognostic importance of clinic and home blood pressure recordings in patients with chronic kidney disease

Abstract

Blood pressure (BP) measured only in the clinic substantially misclassifies hypertension in patients with chronic kidney disease (CKD). The role of out-of-clinic recordings of BP in predicting end-stage renal disease (ESRD) and death in patients with CKD is unknown. A prospective cohort study was conducted in 217 Veterans with CKD. BP was measured at home and in the clinic by 'routine' and standardized methods. Patients were followed over a median of 3.5 years to assess the end points of total mortality, ESRD or the composite outcome of ESRD or death. Home BP was 147.0±21.4/78.3±11.6 mmHg and clinic BPs were 155.2±25.6/84.7±14.2 mmHg by standardized method and 144.5±24.2/75.4±14.7 mmHg by the 'routine' method. The composite renal end point occurred in 75 patients (34.5%), death in 52 patients (24.0%), and ESRD in 36/178 patients (20.2%). One standard deviation (s.d.) increase in systolic BP increased the risk of renal end point by 1.27 (95% confidence interval (CI) 1.01-1.60) for routine clinic measurement, by 1.69 (95% CI 1.32-2.17) for standardized clinic measurement and by 1.84 (95% CI 1.46-2.32) for home BP recording. One s.d. increase in home systolic BP increased the risk of ESRD by 1.74 (95% CI 1.04-2.93) when adjusted for standardized clinic systolic BP, proteinuria, estimated glomerular filtration rate, and other risk factors. In patients with CKD, BPs obtained at home are a stronger predictor of ESRD or death compared to BPs obtained in the clinic. Systolic home BP is an independent predictor for ESRD. © 2006 International Society of Nephrology.