Long-term peri-dialytic blood pressure changes are related to mortality


 
 
 In chronic haemodialysis (HD) patients, the relationship between long-term peri-dialytic blood pressure (BP) changes and mortality has not been investigated before.
 
 
 
 To evaluate whether long-term changes in peri-dialytic BP are related to mortality and whether treatment with HD or haemodiafiltration (HDF) differs in this respect, the combined individual participant data of three randomized controlled trials, comparing HD with HDF, were used. Time-varying Cox regression and joint models were applied.
 
 
 
 During a median follow-up of 2.94 years, 609 out of 2011 patients died. As for pre-dialytic systolic BP (pre-SBP), a severe decline (≥21 mmHg) in the preceding 6 months was independently related to increased mortality (HR 1.61, p = 0.01), if compared to a moderate increase. Likewise, a severe decline in post-dialytic DBP was associated with increased mortality (adjusted HR 1.96, p < 0.0005). Vice versa, joint models showed that every 5 mmHg increase during total follow-up in pre-SBP and post-DBP was related to reduced mortality (aHRs 0.97, p = 0.01 and 0.94, p = 0.03, resp.). No interaction was observed between BP-changes and treatment modality.
 
 
 
 Severe declines in pre-SBP and post-DBP in the preceding 6 months were independently related to mortality. Therefore, peri-dialytic BP-values should be interpreted in the context of their changes and not solely as an absolute value.
