title: 30-Day Readmissions After an Acute Kidney Injury Hospitalization.
abstract: The risk of hospital readmission in acute kidney injury survivors is not well understood. We estimated the proportion of acute kidney injury patients who were rehospitalized within 30 days and identified characteristics associated with hospital readmission.
  
  
  
  We conducted a population-based study of patients who survived a hospitalization complicated by acute kidney injury from 2003-2013 in Ontario, Canada. The primary outcome was 30-day hospital readmission. We used a propensity score model to match patients with and without acute kidney injury, and a Cox proportional hazards model with death as a competing risk to identify predictors of 30-day readmission.
  
  
  
  We identified 156,690 patients who were discharged from 197 hospitals after an episode of acute kidney injury. In the subsequent 30 days, 27,457 (18%) patients were readmitted; 15,988 (10%) visited the emergency department and 7480 (5%) died. We successfully matched 111,778 patients with acute kidney injury 1:1 to patients without acute kidney injury. The likelihood of 30-day readmission was higher in acute kidney injury patients than those without acute kidney injury (hazard ratio [HR] 1.53; 95% confidence interval [CI], 1.50-1.57). Factors most strongly associated with 30-day rehospitalization were the number of hospitalizations in the preceding year (adjusted HR 1.45 for ≥2 hospitalizations; 95% CI, 1.40-1.51) and receipt of inpatient chemotherapy (adjusted HR 1.44; 95% CI, 1.32-1.58).
  
  
  
  One in 5 patients who survive a hospitalization complicated by acute kidney injury is readmitted in the next 30 days. Better strategies are needed to identify and care for acute kidney injury survivors in the community.
authors.affiliation: Division of Nephrology, St. Michael's Hospital and the University of Toronto, Ont, Canada. Electronic address: sam.silver@utoronto.ca.
authors.forename: Samuel A
authors.initials: SA
authors.lastname: Silver
authors.affiliation: Division of Nephrology, St. Michael's Hospital and the University of Toronto, Ont, Canada; Li Ka Shing Knowledge Institute of St Michael's Hospital, University of Toronto, Ont, Canada; Institute for Clinical Evaluative Sciences, Toronto, Ont, Canada.
authors.forename: Ziv
authors.initials: Z
authors.lastname: Harel
authors.affiliation: Institute for Clinical Evaluative Sciences, Toronto, Ont, Canada.
authors.forename: Eric
authors.initials: E
authors.lastname: McArthur
authors.affiliation: Institute for Clinical Evaluative Sciences, Toronto, Ont, Canada.
authors.forename: Danielle M
authors.initials: DM
authors.lastname: Nash
authors.affiliation: Division of Nephrology, London Health Sciences Centre, Western University, Ont, Canada.
authors.forename: Rey
authors.initials: R
authors.lastname: Acedillo
authors.affiliation: Division of Nephrology, St. Michael's Hospital and the University of Toronto, Ont, Canada.
authors.forename: Abhijat
authors.initials: A
authors.lastname: Kitchlu
authors.affiliation: Institute for Clinical Evaluative Sciences, Toronto, Ont, Canada; Division of Nephrology, London Health Sciences Centre, Western University, Ont, Canada.
authors.forename: Amit X
authors.initials: AX
authors.lastname: Garg
authors.affiliation: Division of Nephrology, Stanford University School of Medicine, Palo Alto, Calif.
authors.forename: Glenn M
authors.initials: GM
authors.lastname: Chertow
authors.affiliation: Institute for Clinical Evaluative Sciences, Toronto, Ont, Canada; Department of Medicine, Mount Sinai Hospital, University of Toronto, Ont, Canada; Department of Medicine and Institute of Health Policy, Management, and Evaluation, University of Toronto, Ont, Canada.
authors.forename: Chaim M
authors.initials: CM
authors.lastname: Bell
authors.affiliation: Division of Nephrology, St. Michael's Hospital and the University of Toronto, Ont, Canada; Li Ka Shing Knowledge Institute of St Michael's Hospital, University of Toronto, Ont, Canada; Institute for Clinical Evaluative Sciences, Toronto, Ont, Canada.
authors.forename: Ron
authors.initials: R
authors.lastname: Wald
mesh_terms: D058186:Acute Kidney Injury / Q000401:mortality / Q000628:therapy*; D000368:Aged; D000369:Aged, 80 and over; D015897:Comorbidity; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008875:Middle Aged; D009864:Ontario; D010359:Patient Readmission / Q000706:statistics & numerical data*; D057216:Propensity Score; D016016:Proportional Hazards Models; D012307:Risk Factors; D013997:Time Factors
keywords: Acute kidney injury; Care transitions; Hospital readmissions; Quality of care