title: Trends in hospitalizations among medicare survivors of aortic valve replacement in the United States from 1999 to 2010.
abstract: BACKGROUND
  Mortality rates after aortic valve replacement have declined, but little is known about the risk of hospitalization among survivors and how that has changed with time.
  
  
  METHODS
  Among Medicare patients who underwent aortic valve replacement from 1999 to 2010 and survived to 1 year, we assessed trends in 1-year hospitalization rates, mean cumulative length of stay (average number of hospitalization days per patient in the entire year), and adjusted annual Medicare payments per patient toward hospitalizations. We characterized hospitalizations by principal diagnosis and mean length of stay.
  
  
  RESULTS
  Among 1-year survivors of aortic valve replacement, 43% of patients were hospitalized within that year, of whom 44.5% were hospitalized within 30 days (19.2% for overall cohort). Hospitalization rates were higher for older (50.3% for >85 years), female (45.1%), and black (48.9%) patients. One-year hospitalization rate decreased from 44.2% (95% confidence interval, 43.5 to 44.8) in 1999 to 40.9% (95% confidence interval, 40.3 to 41.4) in 2010. Mean cumulative length of stay decreased from 4.8 days to 4.0 days (p < 0.05 for trend); annual Medicare payments per patient were unchanged ($5,709 to $5,737; p = 0.32 for trend). The three most common principal diagnoses in hospitalizations were heart failure (12.7%), arrhythmia (7.9%), and postoperative complications (4.4%). Mean length of stay declined from 6.0 days to 5.3 days (p < 0.05 for trend).
  
  
  CONCLUSIONS
  Among Medicare beneficiaries who survived 1 year after aortic valve replacement, 3 in 5 remained free of hospitalization; however, certain subgroups had higher rates of hospitalization. After the 30-day period, the hospitalization rate was similar to that of the general Medicare population. Hospitalization rates and cumulative days spent in hospital decreased with time.
authors.affiliation: Center for Outcomes Research and Evaluation, Yale-New Haven Hospital, New Haven, Connecticut; Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut.
authors.forename: Karthik
authors.initials: K
authors.lastname: Murugiah
authors.affiliation: Department of Biostatistics, Harvard School of Public Health, Boston, Massachusetts.
authors.forename: Yun
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Leon H. Charney Division of Cardiology, Department of Medicine, New York University School of Medicine, New York, New York.
authors.forename: John A
authors.initials: JA
authors.lastname: Dodson
authors.affiliation: Center for Outcomes Research and Evaluation, Yale-New Haven Hospital, New Haven, Connecticut.
authors.forename: Sudhakar V
authors.initials: SV
authors.lastname: Nuti
authors.affiliation: Center for Outcomes Research and Evaluation, Yale-New Haven Hospital, New Haven, Connecticut; Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut.
authors.forename: Kumar
authors.initials: K
authors.lastname: Dharmarajan
authors.affiliation: Center for Outcomes Research and Evaluation, Yale-New Haven Hospital, New Haven, Connecticut.
authors.forename: Isuru
authors.initials: I
authors.lastname: Ranasinghe
authors.affiliation: Department of Health Policy and Management, Yale School of Public Health, New Haven, Connecticut; Department of Economics, Yale University, New Haven, Connecticut; Institution for Social and Policy Studies, Yale University, New Haven, Connecticut.
authors.forename: Zack
authors.initials: Z
authors.lastname: Cooper
authors.affiliation: Center for Outcomes Research and Evaluation, Yale-New Haven Hospital, New Haven, Connecticut; Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut; Department of Health Policy and Management, Yale School of Public Health, New Haven, Connecticut; Robert Wood Johnson Foundation Clinical Scholars Program, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut. Electronic address: harlan.krumholz@yale.edu.
authors.forename: Harlan M
authors.initials: HM
authors.lastname: Krumholz
mesh_terms: D000368:Aged; D001021:Aortic Valve / Q000601:surgery*; D005260:Female; D019918:Heart Valve Prosthesis Implantation; D006760:Hospitalization / Q000639:trends*; D006801:Humans; D008297:Male; D006278:Medicare; D011183:Postoperative Complications / Q000453:epidemiology*; D017741:Survivors; D013997:Time Factors; D014481:United States