Long-term prognosis with home hemodialysis. A comparison with other renal replacement therapies

Sammanfattning: Background: The annual mortality for patients on dialysis is high even if it has decreased from 30 % in 1991 to 18 % in 2016. It is mainly caused by an increased cardiovascular and infectious morbidity. Previous studies have reported improved survival for patients with home hemodialysis (HHD). However, patients starting HHD are younger and healthier compared to patients starting other dialysis modalities. The aims of this thesis are to investigate the survival of Swedish patients starting with HHD as initial RRT, to analyse the major non-modifiable factors predicting survival and to study whether there is a benefit beyond patient selection in patient survival, health care utilization and subsequent renal graft survival for patients starting HHD compared with patients starting IHD or PD. An additional aim is to compare the effect on some modifiable risk factors between HHD and IHD. Methods:The studies in this thesis are retrospective observational studies based on data from patient records in study I and II and data from Swedish Renal Registry and the Swedish Inpatient Registry in study III and IV. In study I patients starting HHD at Lund University hospital 1971-1998 were included. In study II patients starting HHD at Lund University hospital 1983-2002 were matched with patients starting IHD at Malmö General Hospital. In study III and IV, all Swedish patients starting HHD during 1991-2012 were matched with patients starting IHD and PD. Matching was performed according to sex, age, Davies Comorbidity Index in study II, Charlson comorbidity index in study III-IV and date of start of dialysis, Results:The annual mortality for patients starting HHD in Lund was 4.9 %. Age, comorbidity and decade of start of HHD had a significant impact on survival. For patients younger than 60 years without comorbidies, subsequent renal transplantations did not have a significant impact on survival. (Study I)Patients starting HHD have a significant superior median survival, 18.5 years, compared with patients starting IHD, 11.9 years, or PD, 15.0 years (Study III).Patients starting HHD have less health care consumption measured as hospital admissions compared with IHD and PD. This advantage is partly caused by less admissions with cardiovascular diagnoses compared IHD and less admissions with infectious disease diagnoses and longer dialysis technique survival compared with PD. (Study IV).There was no significant difference in subsequent renal graft surival after HHD compared to IHD or PD (Study III). Contributing modifiable factors to the improved prognosis for patients on HHD are less prescribed antihypertensives and diuretics, as indirect measures of improved fluid balance, and lower phosphate levels, compared to patients on IHD. (Study II)Conclusion: Patients starting HHD as initial RRT exhibit an improved long-term prognosis beyond differences in patient selection, a superior survival and less health care utilization, compared with patients starting IHD or PD. The results of this thesis are strong incentives for increased use of HHD for patients on maintenance dialysis.