No abstract

SummaryBackground and objectives Increasing BP during maintenance hemodialysis or intradialytic hypertension is associated with increased morbidity and mortality. In hemodialysis patients, ambulatory BP measurements predict adverse cardiovascular outcomes better than in-center measurements. We hypothesized that patients with intradialytic hypertension have higher interdialytic ambulatory systolic BP than those without intradialytic hypertension. Design, setting, participants, & measurementsWe performed a case-control study in adult hemodialysis patients. Cases consisted of subjects with intradialytic-hypertension (systolic BP increase Ն10 mmHg from pre-to posthemodialysis in at least four of six treatments), and controls were subjects with Ն10 mmHg decreases from pre-to posthemodialysis in at least four of six treatments. The primary outcome was mean interdialytic 44-hour systolic ambulatory BP.Results Fifty subjects with a mean age of 54.5 years were enrolled (25 per group) among whom 80% were men, 86% diabetic, 62% Hispanic, and 38% African American. The mean prehemodialysis systolic BP for the intradialytic-hypertension and control groups were 144.0 and 155.5 mmHg, respectively. Mean posthemodialysis systolic BP was 159.0 and 128.1 mmHg, for the intradialytic-hypertension and control groups, respectively. The mean systolic ambulatory BP was 155.4 and 142.4 mmHg for the intradialytic-hypertension and control groups, respectively (P ϭ 0.005). Both daytime and nocturnal systolic BP were higher among those with intradialytic hypertension as compared with controls. There was no difference in interdialytic weight gain between groups.Conclusions Time-integrated BP burden as measured by 44-hour ambulatory BP is higher in hemodialysis patients with intradialytic hypertension than those without intradialytic hypertension.

Intradialytic hypertension is a persistent phenomenon in a subset of hemodialysis patients. Ultrafiltration rate was the only volume-related variable that differed between patients with and without persistent intradialytic hypertension.

Background/Aims: Intradialytic hypertension (IH) occurs frequently in some hemodialysis patients and increases mortality risk. We simultaneously compared pre-dialysis, post-dialysis and changes in extracellular volume and hemodynamics in recurrent IH patients and controls. Methods: We performed a case-control study among prevalent hemodialysis patients with recurrent IH and hypertensive hemodialysis controls. We used bioimpedance spectroscopy and impedance cardiography to compare pre-dialysis, post-dialysis, and intradialytic change in total body water (TBW) and extracellular water (ECW), as well as cardiac index (CI) and total peripheral resistance index (TPRI). Results: The ECW/TBW was 0.453 (0.05) pre-dialysis and 0.427 (0.04) post-dialysis in controls vs. 0.478 (0.03) and 0.461 (0.03) in IH patients (p=0.01 post-dialysis). The ECW/TBW change was -0.027 (0.03) in controls and -0.013 (0.02) in IH patients (p=0.1). In controls, pre- and post-dialysis TPRI were 3254 (994) and 2469 (529) dynes/sec/cm²/m² vs. 2983 (747) and 3408 (980) dynes/sec/cm²/m² in IH patients (p=0.002 post-dialysis). There were between-group differences in TPRI change (0=0.0001), but not CI (p=0.09). Conclusions: Recurrent intradialytic hypertension is associated with higher post-dialysis extracellular volume and TPRI. Intradialytic TPRI surges account for the vasoconstrictive state post-dialysis, but intradialytic fluid shifts may contribute to post-hemodialysis volume expansion.