Blood pressure management in patients receiving renal replacement therapy

Which blood pressure metrics should be used in patients on dialysis?

Remarkable progress has recently been achieved in blood pressure (BP) control based on key research findings in the general population. It has been observed that maintaining BP slightly lower than previously recommended goals leads to better clinical outcomes, provided that patients can tolerate it. Previously, BP control targets for dialysis patients were extrapolated from studies conducted on the general population. However, dialysis patients are considered a distinct group with unique characteristics, which makes defining appropriate BP targets a matter of debate. Several observational studies measuring BP in hemodialysis (HD) patients within dialysis units have shown that lower peridialysis BP (pre-, post-, and interdialytic BP) is associated with worse clinical outcomes. However, this association is likely confounded by factors specific to dialysis patients. The relationship between BP and mortality appears to be more linear in patients with fewer underlying cardiovascular diseases and longer survival. Recent studies have indicated that BP measurements taken outside of dialysis sessions, such as standardized BP on nondialysis days, home BP, and ambulatory BP monitoring between HD sessions, are more predictive of clinical outcomes. Due to the varied effects of dialysis-related treatment practices on BP, there is a lack of data from large-scale clinical trials. As a result, it is challenging to provide strong recommendations for BP targets directly applicable to dialysis patients. This review addresses various factors influencing BP in dialysis patients, including the establishment of individualized target BP levels and discussions on maintenance strategies, while incorporating a recent literature review.

Seasonal variation and predictors of intradialytic blood pressure decline: a retrospective cohort study

The risk factors for intradialytic systolic blood pressure decline remain poorly understood. We aimed to identify clinical and laboratory predictors of the intradialytic systolic blood pressure decline, considering its seasonal variation. In a retrospective cohort of 47,219 hemodialysis sessions of 307 patients undergoing hemodialysis over one year in three dialysis clinics, the seasonal variation and the predictors of intradialytic systolic blood pressure decline (predialysis systolic blood pressure--nadir intradialytic systolic blood pressure) were assessed using cosinor analysis and linear mixed models adjusted for baseline or monthly hemodialysis-related variables, respectively. The intradialytic systolic blood pressure decline was greatest and least in the winter and summer, respectively, showing a clear seasonal pattern. In both models adjusted for baseline and monthly hemodialysis-related parameters, calcium channel blocker use was associated with a smaller decline (-4.58 [95% confidence interval (CI), -5.84 to -3.33], P < 0.001; -3.66 [95% CI, -5.69 to -1.64], P < 0.001) and α blocker use, with a greater decline (3.25 [95% CI, 1.53-4.97], P < 0.001; 3.57 [95% CI, 1.08-6.06], P = 0.005). Baseline and monthly serum phosphorus levels were positively correlated with the decline (1.55 [95% CI, 0.30-2.80], P = 0.02; 0.59 [95% CI, 0.16-1.00], P = 0.007), and baseline and monthly normalized protein catabolic rates were inversely correlated (respectively, -22.41 [95% CI, -33.53 to -11.28], P < 0.001; 9.65 [95% CI, 4.60-14.70], P < 0.001). In conclusion, calcium channel blocker use, α blocker avoidance, and serum phosphorus-lowering therapy may attenuate the intradialytic systolic blood pressure decline and should be investigated in prospective trials.