Predialysis systolic blood pressure correlates strongly with mean 24-hour systolic blood pressure and left ventricular mass in stable hemodialysis patients

This study used a 24-h ambulatory blood pressure (ABP) monitor to study the relationship between dialysis room-measured blood pressures (BP) and mean 24-h systolic and diastolic ambulatory BP (SABP and DABP) with left ventricular mass (LV) in a group of 35 stable hemodialysis patients. Predialysis and postdialysis systolic and diastolic blood pressure data were collected for the 12 dialysis treatments before the wearing of the ABP device, and the means of these values are reported. All patients were maintained on the same antihypertensive medications for 3 months before the study and had a stable hematocrit value of 30 +/- 3% during this time period. There was no difference detected between daytime and nighttime ABP, SABP was a mean of 4.7 mm Hg below predialysis systolic BP (P = 0.004) and DABP was a mean of 3.7 mm Hg below predialysis diastolic BP. There was a strong correlation between SABP and predialysis systolic BP (r = 0.67, P = 0.0001); however, postdialysis diastolic BP correlated better with DABP than did predialysis diastolic BP. In addition, LV mass correlated with SABP (r = 0.35, P = 0.03) and predialysis systolic BP (r = 0.35, P = 0.03). There was no apparent correlation between either pre- or postdialysis diastolic BP with LV mass. It was concluded that predialysis systolic BP and postdialysis diastolic BP correlates strongly with SABP and DABP. Furthermore, predialysis systolic BP correlates with LV mass in hemodialysis patients. If the deleterious effects of hypertension in this patient population are to be avoided, it is the predialysis systolic BP that needs to be controlled: it is insufficient to be satisfied with good postdialysis BP control, if patients are hypertensive before beginning dialysis.