Survival on four compared with three times per week haemodialysis in high ultrafiltration patients: an observational study

Abstract

Background The harm caused by the long interdialytic interval in three-times-per-week haemodialysis regimens (3×WHD) may relate to fluid accumulation and associated high ultrafiltration rate (UFR). Four-times-per-week haemodialysis (4×WHD) may offer a solution, but its impact on mortality, hospitalization and vascular access complications is unknown. Methods From the AROii cohort of incident in-centre haemodialysis patients, 3×WHD patients with a UFR >10 mL/kg/h were identified. The hazard for the outcomes of mortality, hospitalization and vascular access complications in those who switched to 4×WHD compared with staying on 3×WHD was estimated using a marginal structural Cox proportional hazards model. Adjustment included baseline patient and treatment characteristics with inverse probability weighting used to adjust for time-varying UFR and cardiovascular comorbidities. Results From 10 637 European 3×WHD patients, 3842 (36%) exceeded a UFR >10 mL/kg/h. Of these, 288 (7.5%) started 4×WHD and at baseline were more comorbid. Event rates while receiving 4×WHD compared with 3×WHD were 12.6 compared with 10.8 per 100 patient years for mortality, 0.96 compared with 0.65 per year for hospitalization and 14.7 compared with 8.0 per 100 patient years for vascular access complications. Compared with 3×WHD, the unadjusted hazard ratio (HR) for mortality on 4×WHD was 1.05 [95% confidence interval (CI) 0.78–1.42]. Following adjustment for baseline demographics, time-varying treatment probability and censoring risks, this HR was 0.73 (95% CI 0.50–1.05; P = 0.095). Despite these adjustments on 4×WHD, the HR for hospitalization remained elevated and vascular access complications were similar to 3×WHD. Conclusions This observational study was not able to demonstrate a mortality benefit in patients switched to 4×WHD. To demonstrate the true benefits of 4×WHD requires a large, well-designed clinical trial. Our data may help in the design of such a study.

Patient Preferences for Longer or More Frequent In-Center Hemodialysis Regimens: A Multicenter Discrete Choice Study

“…A third of patients in our study had been approached about more intensive regimens and real world data suggests around 3.5% subsequently receiving four times a week dialysis and 18% receiving 4.5hrs 3xW in clinical practice. 12,13 Discrepancies between real-world use and predicted uptake could relate to observed and unobserved differences in the cohorts approached, patient interpretation of the choice scenario or the J o u r n a l P r e -p r o o f statistical models. To tackle the long interdialytic interval, the fourth session should ideally be scheduled during this period, although some patients may wish to preserve a 2-day gap.…”

“…This ensured sufficient experience of in-center HD to consider and relate to the scenario and aligned with the informing studies in which the majority of patients who received these treatments had been dialyzing in excess of 1 year. 12 , 13 The exclusion criteria were an existing diagnosis of malignancy (because patients with a limited life expectancy may not be offered these regimens and may have their treatment shortened toward the end of life), 12 or the presence of a formal diagnosis of cognitive impairment in the medical notes, or the presence of cognitive impairment as assessed by the dialysis nursing staff or the researcher conducting the questionnaire.…”

“…The questionnaire booklet begins by asking participants to consider a scenario where they were an in-center HD patient who after 2 years of treatment had developed high ultrafiltration rates and significant fatigue. In the scenario, the staff at the dialysis unit hypothetically offer them these treatments: longer sessions (4.5 hours) provided 3 times per week, 12 more frequent (4 times per week) 4-hour duration HD, 13 or remaining on the current 4 hours provided 3 times per week (an opt-out choice). The questionnaire then asks the participant to consider which HD regimen they would select in this scenario 12 times.…”

“…In order to predict acceptance, existing evidence between attributes and the treatment regimens being offered informed the attribute and level selection. 7 , 12 , 13 , 17 , 18 Each of the 12 DCE questions included a labeled description of longer, 4-times-a-week, and continuing 3-times-a-week HD and the attributes associated with them for that particular DCE choice set. Table 1 shows an example of the attributes presented to the patient for the third DCE choice set, which illustrates the range of levels each attribute could take: survival (9, 10, 12, or 14 years), quality of life (you feel the same; you feel better), fluid restriction (you can drink the same; you can drink more), hospitalization (once a year; once every 2 years), and access complications (no change; more complications).…”

“…11 We present a DCE conducted across five centres in the United Kingdom, designed to elicit patient preferences towards longer session length as part of a three times a week dialysis schedule, four times a week haemodialysis, or remaining on the standard three times a week regimen, all delivered in-centre. 12,13 Accounting for individual patient characteristics which influence these preferences, we estimate the acceptance of these more intensive regimens in the presence of benefits and harms identified in the literature for a prevalent population and specific groups.…”