PULSE WAVE VELOCITY NON-DIPPING PATTERN IS ASSOCIATED WITH CARDIOVASCULAR MORTALITY IN HYPERTENSIVE PATIENTS UNDERGOING CHRONIC HEMODIALYISIS

Abstract

Objective: Increased arterial stiffness is established as an independent cardiovascular (CV) risk factor. Although this association was found also in patients undergoing hemodialysis (HD), reports are frequently contradictory largely because measurements were obtained shortly before or after HD. The aim of our study was to analyze circadian variations of aortic stiffness using ABPM device which provides valid measures in ambulatory conditions and association with CV mortality. Design and method: A total of 31 hypertensive patients (19 M, 12 F; averaged age 59.4) who had been on intermittent HD treatment for more than 6 months were enrolled in this study (22.6% diabetic, 16.1% smokers) and followed up for average 18.6 months. Patients received HD treatment 4 hr/session three times a week during the study period. TensioMed Arteriograph which records oscillometric BP and pulse waveforms at the brachial artery and provides valid measures of aortic BP, AIx, and PWV in ambulatory conditions was applied on non-dialysis midweek day. Control group consist of 25 healthy subjects without prior diabetes, CKD, hypertension and hyperlipidemia. Results: Systolic BP, PWV and AIx non-dipping patterns were found in 74.2%, 64.5% and 61.3% of patients. We failed to find difference in AIx dipping pattern between patients and control subjects (38.7% vs. 28.0%; p = 0.4) while PWV non-dipping pattern was significantly more frequently found in HD patients (64.5% vs. 16.0%, p < 0.001). At the end of follow-up period 13 (41.9%) patient died from CV deaths. We have not found any differences in age, dialysis parameters, comorbidity, HD therapy and laboratory parameters between survived and deceased HD patients. Differences in basal systolic and diastolic BP, PWV, AIx between survived and deceased were not statistically significant. There were no differences in number of BP and AIx non-dippers between survived and deceased patients while significantly higher number of deceased patients had PWV nocturnal non-dipping pattern (84.5% vs.50.0%, p = 0.04). Conclusions: A newly introduced ABPM devices for ambulatory recordings provide new insights on importance of arterial stiffnes for CV moratlity in patients undergoing HD. Our results showed that PWV non-dipping pattern is independently associated with CV moratily.