Background: Cardiovascular disease remains the leading cause of death among patients with end-stage renal disease (ESRD). Nocturnal home hemodialysis (NHD) (5 - 6 sessions per week; 6 - 8 hours per session) is a novel form of home-based renal replacement therapy, which has been shown to improve several cardiovascular risk factors. The impact of NHD on hospitalization rate has remained unclear. We hypothesized that augmentation of small and middle molecular clearance by NHD would result in a reduction of dialysis related or cardiovascular specific hospitalizations.
Methods and results: In this controlled cohort study, we studied 32 NHD patients (age: 43 +/- 2 [mean +/- SEM]) 1 year before and 2 years after conversion to NHD and 42 CHD patients (mean age: 44 +/- 2) (matched for age, dialysis vintage and controlled for comorbidities) during the same time period. The primary outcome was the change in a composite of dialysis or cardiovascular related admissions rate before and after conversion to NHD. Secondary outcomes included changes in all cause hospitalization rate, visits to emergency, reasons and duration of hospitalization and dialysis-related biochemical parameters. During the study period, dialysis or cardiovascular-related admission rate was stable for the CHD control cohort (from 0.48 +/- 0.14 [baseline] to 0.40 +/- 0.12 [end of study] admission per patient year, p = NS). In contrast, conversion to NHD is associated with a decrease in our composite endpoint (from 0.50 +/- 0.15 to 0.17 +/- 0.06 admission per patient year, p = 0.04). Cardiovascular disease (37%) was the principal cause for hospitalization in the control population. In comparison, vascular access related admission was the primary cause of admission for the NHD cohort (56%), p = 0.001. Of the biochemical parameters, NHD is associated with a decrease in plasma phosphate (from 1.7 +/- 0.1 to 1.3 +/- 0.1 mM, p = 0.01) and an improved control of anemia (from 114 +/- 2 to 122 +/- 3 g/l, p = 0.02).
Conclusion: Conversion to NHD is associated with a decrease in dialysis and cardiovascular-related hospital admission. The clinical and mechanistic relevance in uremic patients of improved phosphate and anemia management requires further examination.