Central blood pressure and cardiovascular outcomes in chronic kidney disease

Background and objectives Central BP measurements provide noninvasive measurement of aortic BP; our objectives were to examine the association of central and brachial BP measurements with risk of cardiovascular outcomes and mortality in patients with CKD and to determine the role of central BP measurement in conjunction with brachial BP in estimating cardiovascular risk. Design, setting, participants, &measurements Inaprospective, longitudinal study (the Chronic Renal Insufficiency Cohort), central BP was measured in participants with CKD using the SphygmoCorPVx System. Cox proportional hazards models were used for analyses. Results Mean age of the participants (n=2875) was 60 years old. After a median follow-up of 5.5 years, participants in the highest quartile of brachial systolic BP (≥138 mm Hg) were at higher risk for the composite cardiovascular outcome (hazard ratio, 1.59; 95% confidence interval, 1.17 to 2.17; c statistic, 0.76) but not all-cause mortality (hazard ratio, 1.28; 95% confidence interval, 0.90 to 1.80) compared with those in the lowest quartile. Participants in the highest quartile of central systolic BP were also at higher risk for the composite cardiovascular outcome (hazard ratio, 1.69; 95% confidence interval, 1.24 to 2.31; c statistic, 0.76) compared with participants in the lowest quartile. Conclusions We show that elevated brachial and central BP measurements are both associated with higher risk of cardiovascular disease outcomes in patients with CKD. Measurement of central BP does not improve the ability to predict cardiovascular disease outcomes or mortality in patients with CKD compared with brachial BP measurement.