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Increased blood pressure (BP) variability (BPV) is associated with high cardiovascular risk in hemodialysis. Studies on the effects of antihypertensive drugs on BPV in hemodialysis are scarce. This study examines the effects of nebivolol and irbesartan on short-term BPV in patients with intradialytic hypertension. This randomized-cross-over study included 38 patients (age: 60.4 ± 11.1 years, male: 65.8%) with intradialytic hypertension (intradialytic-SBP increase ≥ 10 mmHg at ≥4 over 6 consecutive sessions). After the baseline evaluation, participants were randomized to nebivolol 5 mg and subsequently irbesartan 150 mg, or vice versa, with a two-week wash-out period before initiation of the second drug. Patients underwent three respective 24 h-ABPM sessions starting before a midweek-session. We calculated the standard deviation (SD), weighted SD (wSD), coefficient of variation (CV), and average real variability (ARV) of BP with validated formulas. The post-hemodialysis and 24 h-SBP and DBP levels were significantly lower after treatment with both drugs. The systolic-BPV indices were marginally lower after nebivolol but not after irbesartan compared to baseline (SD: baseline 15.70 ± 4.69; nebivolol 14.45 ± 3.37, p = 0.090; irbesartan 15.39 ± 3.85, p = 0.706; wSD: 14.62 ± 4.36 vs 13.40 ± 3.07, p = 0.053 vs 14.36 ± 3.47, p = 0.805, respectively). The diastolic-BPV indices decreased with nebivolol and increased with irbesartan, resulting in significant differences between the two drugs (SD: baseline 10.56 ± 2.50; nebivolol 9.75 ± 2.12; irbesartan 10.84 ± 1.98, between-drug p = 0.014; wSD: baseline 9.86 ± 2.12; nebivolol 9.34 ± 2.01; irbesartan 10.25 ± 2.01, between-drug p = 0.029). The diastolic-BPV during intradialytic and day-time periods was marginally lower with nebivolol than with irbesartan. During nighttime, the BPV indices were unchanged with either drug. The short-term BPV was reduced after nebivolol but not after irbesartan treatment in patients with intradialytic hypertension. These findings suggest that sympathetic-overdrive may be a major factor that affects BPV in intradialytic hypertension patients.

Background: Long-term pre-dialysis blood pressure variability (BPV) in haemodialysis patients is associated with increased cardiovascular risk. The association of the main haemodynamic culprit in dialysis, that is, short-term BPV, with outcomes has not been investigated. We examine the prognostic role of short-term BPV for mortality and cardiovascular events in this population., Methods: A total of 227 haemodialysis patients underwent 44-h ambulatory monitoring during a standard interval and were followed-up for 30.17 ± 17.70 months. We calculated SD, weighted SD (wSD), coefficient of variation (CV) and average real variability (ARV) of BP with validated formulas. The primary endpoint was first occurrence of all-cause death, non-fatal myocardial infarction or non-fatal stroke. Secondary endpoints were: (i) all-cause mortality, (ii) cardiovascular mortality and (iii) a combination of cardiovascular events., Results: Cumulative freedom from the primary endpoint was similar for quartiles of pre-dialysis and 44-h systolic BP (SBP), but was progressively longer for increasing quartiles of 44-h SBP-SD (P = 0.014), wSD (P = 0.007), CV (P = 0.031) and ARV (83.9, 71.9, 70.2 and 43.9% for quartiles 1-4; P < 0.001). Higher quartiles of 44-h SBP-ARV were associated with higher risk of all studied outcomes. Among diastolic BPV indices, 44-h diastolic BP (DBP)-CV and 44-h DBP-ARV were associated with increased risk for the composite cardiovascular outcome. In Cox regression analysis, SBP-BPV was related to the primary endpoint, independently of SBP levels and interdialytic weight gain [ARV: hazard ratio (HR) 1.115, 95% confidence interval (95% CI) 1.048-1.185]. This association become insignificant after adjustment for pulse wave velocity (PWV; HR 1.061, 95% CI 0.989-1.137), and further attenuated after additional adjustment for age, dialysis vintage, gender, comorbidities and prevalent cardiovascular disease (HR 1.031, 95% CI 0.946-1.122)., Conclusions: Increased BPV during the interdialytic interval is associated with higher risk of death and cardiovascular events, whereas ambulatory BP levels are not. This association was not independent after adjustment for PWV, other risk factors and prevalent cardiovascular disease. Short-term BPV could be a mediator promoting the adverse cardiovascular profile of haemodialysis patients., (© The Author(s) 2018. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.)

Background: Increased arterial stiffness and aortic blood pressure (BP) are independent predictors of cardiovascular outcomes in end-stage renal disease. The 3-day interdialytic interval is associated with elevated risk of cardiovascular morbidity and mortality in haemodialysis. This study investigated differences in ambulatory aortic BP and arterial stiffness between the second and third day of the long interdialytic interval., Methods: Ambulatory BP monitoring with Mobil-O-Graph monitor (IEM, Stolberg, Germany) was performed in 55 haemodialysis patients during a 3-day interval. Mobil-O-Graph records oscillometric brachial BP and pulse waves and calculates aortic BP and augmentation index (AIx) as measure of wave reflections, and pulse wave velocity (PWV) as measure of arterial stiffness., Results: Ambulatory aortic systolic blood pressure (SBP) and diastolic blood pressure (DBP) were higher during the third versus second interdialytic day (123.6 ± 17.0 versus 118.5 ± 17.1 mmHg, P < 0.001; 81.5 ± 11.8 versus 78 ± 11.9 mmHg, P < 0.001, respectively). Similar differences were noted for brachial BP. Ambulatory AIx and PWV were also significantly increased during the third versus second day (30.5 ± 9.9 versus 28.8 ± 9.9%, P < 0.05; 9.6 ± 2.3 versus 9.4 ± 2.3 m/s, P < 0.001, respectively). Differences between Days 2 and 3 remained significant when day-time and night-time periods were compared separately. Aortic SBP and DBP, AIx and PWV showed gradual increases from the end of dialysis session onwards. Interdialytic weight gain was a strong determinant of the increase in the above parameters., Conclusions: This study showed significantly higher ambulatory aortic BP, AIx and PWV levels during the third compared with the second interdialytic day. These findings support a novel pathway for increased cardiovascular risk during the third interdialytic day in haemodialysis., (© The Author 2015. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.)