Burden and causes of hospital admissions and readmissions in patients undergoing hemodialysis and peritoneal dialysis: a nationwide study

Background High rates of hospitalization in dialysis patients impose an increasing healthcare burden. We explored and compared hospital admission rates among patients starting hemodialysis (HD) and peritoneal dialysis (PD), and investigated causes of admission/readmission in search of potentially preventable risks. Methods Observational study recruiting 8902 patients (3101 on PD) who started maintenance dialysis in Sweden between 2006 and 2016 and were followed-up for 2 years. We compared the Hazard Ratios (HR) for hospital admission and in-hospital death, and calculated the odds ratios (OR) of readmission within 30 days after discharge. Results Six thousand four hundred ninety-three (73%) patients were hospitalized at least once, and 246 admissions ended with in-hospital death. Compared with HD, patients on PD had a higher risk of hospitalization (HR 1.07; 95% CI 1.01-1.13), longer length of stay (mean difference of 2.06; 1.39-2.73 days), and higher risk of in-hospital death (HR 1.18; 1.03-1.37). Peritonitis and cardiovascular events were the most frequent causes of admission. Of 5810 patients discharged from the hospital, 1447 (25%) were readmitted and 124 (2%) died within 30 days. No differences in readmission risk were observed between dialysis modalities. There was frequently discordance between the cause of hospital admission and readmission, and we identified a consistent pattern of readmission attributed to complications from infections and their interplay with cardiovascular diseases. Conclusions Our study illustrates a high burden of hospitalization in patients on dialysis, suggests the risk of longer hospitalizations for patients on PD, and identifies cardiovascular events and infections as complications that may benefit from closer post-discharge monitoring.