Prescription patterns of dialysate potassium and potassium binders and survival on haemodialysis—the French Renal Epidemiology and Information Network registry

Background Management of potassium disorders in patients on haemodialysis (HD) is complex. We studied prescription patterns of dialysate potassium and potassium binders, and their associations with patient survival. Methods This national registry-based study included 25 629 incident adult patients alive after 3 months of HD from 2010 through 2013 and followed-up through 31 December 2014. We used Cox proportional hazard models to estimate multiadjusted mortality hazard ratios (HRs) associated with time-dependent exposure to facility-level dialysate potassium concentrations and patient-level potassium binder exposure. Results Almost all dialysis units used, and generally most often, dialysate potassium concentrations of 2 mmol/L. During this period, use of concentrations <2 mmol/L tended to decrease and those ≥3 mmol/L to increase. In 2014, 9% of units used a single dialysate formula, 41% used two and 50% three or more. The most frequent combinations were 2 and 3 mmol/L (40%), and <2, 2 and 3 mmol/L (37%). Compared with patients on HD in units using only one dialysate formula, those in units using two or three had adjusted mortality HRs of 0.91 [95% confidence interval (CI) 0.82–1.01] and 0.84 (0.75–0.93), respectively. Potassium binders were prescribed for 37% of all patients at baseline. Adjusted mortality HRs associated with doses <4, 4–8 and ≥8 g/day versus none were 1.22 (95% CI 1.04–1.51), 0.6 (0.54–0.66) and 0.25 (0.24–0.33), respectively. Conclusions Diversity in facility-level use of dialysate potassium concentrations and potassium binder use at an appropriate dose appear to be associated with better survival in HD patients.