Cardiovascular risks of dipping status and chronic kidney disease in elderly Japanese hypertensive patients

Chronic kidney disease (CKD) increases the risk of cardiovascular events and is often associated with the nondipping pattern of blood pressure (BP). We evaluated ambulatory BP, CKD, and the incidence of cardiovascular events in 811 older hypertensive patients. CKD and the dipping pattern increased the risk of cardiovascular events independent of the 24-hour systolic BP level (CKD: hazard ratio [HR], 2.37; 95% confidence interval [CI], 1.24-4.54; nondippers: HR, 2.16; 95% CI, 1.19-3.91; extreme dippers: HR, 2.38; 95% CI, 1.17-4.83). However, after adjustment for covariates that included CKD, the risk in nondippers was insignificant (HR, 1.83; 95% CI, 0.998-3.34; P=.051), while the risk in extreme dippers remained (HR, 2.59; 95% CI, 1.26-5.32; P=.009) (CKD: HR, 1.81; 95% CI, 0.93-3.54; P=.081). Patients with CKD have an increased risk of cardiovascular events. CKD and other cardiovascular risk factors may account for some of the increased risk in nondippers, but it does not explain the higher risk in extreme dippers.