IMPACT OF BLOOD PRESSURE VARIABILITY ON CARDIOVASCULAR MORTALITY IN CHRONIC KIDNEY DISEASE PATIENTS

Abstract

Objective: It is well known that blood pressure (BP) variability is associated with development of target-organ damage and adverse cardiovascular outcome in hypertensive patients. However, the impact of BP variability (BPV) on cardiovascular outcome in chronic kidney disease patients (CKD) is unclear. Aim of the study was to examine the impact of home BPV on cardiovascular mortality in chronic kidney disease patients. Design and method: A total of 137 CKD patients, referred for evaluation at the Hypertension Unit of our department, underwent home BP monitoring. Participants were instructed to take duplicate morning and evening measurements in the sitting position, after 5-min sitting rest and with 1 min between measurements for 7 working days. The average home BP value of the morning, evening and all measurements was analyzed. Home BPV was quantified by using standard deviation (SD), coefficient of variation (CV) and morning minus evening BP values. Median follow-up for fatal cardiovascular events was 3 years. Statistical analysis was performed by means of cox regression analysis. Results: The study population consisted of 102 men (75%). Mean age was 70 years, mean office BP was 142/76 mmHg and mean home BP was 137/74 mmHg. During follow-up, there were 12 fatal cardiovascular events. The multivariate Cox regression analyses revealed that the SD of systolic home BP was an independent predictor of cardiovascular mortality (HR: 1.19, 95%CI 1.02–1.38, p = 0.022) after adjustment for age, sex, history of diabetes mellitus and hyperlipidemia, smoking, antihypertensive treatment and mean systolic home BP. Conclusions: Home BPV is an independent predictor of cardiovascular mortality in CKD patients