Aortic stiffness, left ventricular hypertrophy and weekly averaged blood pressure (WAB) in patients on haemodialysis

Background. In haemodialysis (HD) patients, no consensus has been reached with regard to the desired blood pressure (BP) level and when or how BP should be monitored. Moreover, BP variability over a period of 1 week has not been well studied in HD patients. Methods. The present study is an observational study that comprised 101 HD patients (65 males and 36 females). We used daily home blood pressure (HBP) monitoring to record a total of 20 points of BP over a period of 1 week, including measurements of the wake-up and night BPs; this was in addition to the BP recorded before and after each HD session that occurred three times a week. The average of these 20 BP measurements was defined as the weekly averaged blood pressure (WAB). Finally, we studied the relationship between the WAB and left ventricular hypertrophy (LVH) or aortic stiffness measured by baPWV. Results. The systolic (142.5 +/- 19.5 mmHg) and diastolic (.78.8 +/- 9.9 mmHg) WABs were almost consistent with the wake-up BP on the day after the midweek dialysis session (R-2 = 0.709 and 0.775, respectively). The WAB showed significant positive correlations with the left ventricular mass index (LVMI) (R = 0.387, P < 0.001) and baPWV (R = 0.226, P < 0.05), whereas the predialysis systolic BP did not show a significant positive correlation with the LVMI. Conclusion. The WAB is a useful marker for evaluating the BP of HD patients and correlates well with the LVMI or baPWV.