title: Trajectories of Risk for Specific Readmission Diagnoses after Hospitalization for Heart Failure, Acute Myocardial Infarction, or Pneumonia.
abstract: BACKGROUND
  The risk of rehospitalization is elevated in the immediate post-discharge period and declines over time. It is not known if the extent and timing of risk vary across readmission diagnoses, suggesting that recovery and vulnerability after discharge differ by physiologic system.
  
  
  OBJECTIVE
  We compared risk trajectories for major readmission diagnoses in the year after discharge among all Medicare fee-for-service beneficiaries hospitalized with heart failure (HF), acute myocardial infarction (AMI), or pneumonia from 2008-2010.
  
  
  METHODS
  We estimated the daily risk of rehospitalization for 12 major readmission diagnostic categories after accounting for the competing risk of death after discharge. For each diagnostic category, we identified (1) the time required for readmission risk to peak and then decline 50% from maximum values after discharge; (2) the time required for readmission risk to approach plateau periods of minimal day-to-day change; and (3) the extent to which hospitalization risks are higher among patients recently discharged from the hospital compared with the general elderly population.
  
  
  RESULTS
  Among >3,000,000 hospitalizations, the yearly rate of rehospitalization was 67.0%, 49.5%, and 55.3% after hospitalization for HF, AMI, and pneumonia, respectively. The extent and timing of risk varied by readmission diagnosis and initial admitting condition. Risk of readmission for gastrointestinal bleeding/anemia peaked particularly late after hospital discharge, occurring 10, 6, and 7 days after hospitalization for HF, AMI, and pneumonia, respectively. Risk of readmission for trauma/injury declined particularly slowly, requiring 38, 20, and 38 days to decline by 50% after hospitalization for HF, AMI, and pneumonia, respectively.
  
  
  CONCLUSIONS
  Patterns of vulnerability to different conditions that cause rehospitalization vary by time after hospital discharge. This finding suggests that recovery of various physiologic systems occurs at different rates and that post-discharge interventions to minimize vulnerability to specific conditions should be tailored to their underlying risks.
authors.affiliation: Section of Cardiovascular Medicine, Department of Internal Medicine, Yale School of Medicine, New Haven, CT, United States of America.|Center for Outcomes Research and Evaluation, Yale-New Haven Hospital, New Haven, CT, United States of America.|Department of Health Policy and Management, Yale School of Public Health, New Haven, CT, United States of America.|Robert Wood Johnson Foundation Clinical Scholars Program, Department of Internal Medicine, Yale School of Medicine, New Haven, CT, United States of America.
authors.forename: Harlan M
authors.initials: HM
authors.lastname: Krumholz
authors.affiliation: Center for Outcomes Research and Evaluation, Yale-New Haven Hospital, New Haven, CT, United States of America.
authors.forename: Angela
authors.initials: A
authors.lastname: Hsieh
authors.affiliation: Center for Outcomes Research and Evaluation, Yale-New Haven Hospital, New Haven, CT, United States of America.
authors.forename: Rachel P
authors.initials: RP
authors.lastname: Dreyer
authors.affiliation: Center for Outcomes Research and Evaluation, Yale-New Haven Hospital, New Haven, CT, United States of America.
authors.forename: John
authors.initials: J
authors.lastname: Welsh
authors.affiliation: Section of Cardiovascular Medicine, Department of Internal Medicine, Yale School of Medicine, New Haven, CT, United States of America.|Center for Outcomes Research and Evaluation, Yale-New Haven Hospital, New Haven, CT, United States of America.
authors.forename: Nihar R
authors.initials: NR
authors.lastname: Desai
authors.affiliation: Section of Cardiovascular Medicine, Department of Internal Medicine, Yale School of Medicine, New Haven, CT, United States of America.|Center for Outcomes Research and Evaluation, Yale-New Haven Hospital, New Haven, CT, United States of America.
authors.forename: Kumar
authors.initials: K
authors.lastname: Dharmarajan
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D018588:Fee-for-Service Plans / Q000706:statistics & numerical data; D005260:Female; D006333:Heart Failure / Q000175:diagnosis*; D006760:Hospitalization / Q000706:statistics & numerical data*; D006761:Hospitals; D006801:Humans; D008297:Male; D006278:Medicare / Q000706:statistics & numerical data; D009203:Myocardial Infarction / Q000175:diagnosis*; D010351:Patient Discharge / Q000706:statistics & numerical data; D010359:Patient Readmission / Q000706:statistics & numerical data*; D011014:Pneumonia / Q000175:diagnosis*; D012306:Risk; D013997:Time Factors; D014481:United States