title: Use of intensive care services and associated hospital mortality after Massachusetts healthcare reform*.
abstract: OBJECTIVE
  To use the natural experiment of health insurance reform in Massachusetts to study the impact of increased insurance coverage on ICU utilization and mortality.
  
  
  METHODS
  Population-based cohort study.
  
  
  METHODS
  Massachusetts and four states (New York, Washington, Nebraska, and North Carolina) that did not enact reform.
  
  
  METHODS
  All nonpregnant nonelderly adults (age 18-64 yr) admitted to nonfederal acute care hospitals in one of the five states of interest were eligible, excluding patients who were not residents of a respective state at the time of admission.
  
  
  METHODS
  We used a difference-in-differences approach to compare trends in ICU admissions and outcomes of in-hospital mortality and discharge destination for ICU patients.
  
  
  RESULTS
  Healthcare reform in Massachusetts was associated with a decrease in ICU patients without insurance from 9.3% to 5.1%. There were no significant changes in adjusted ICU admission rates, mortality, or discharge destination. In a sensitivity analysis excluding a state that enacted Medicaid reform prior to the study period, our difference-in-differences analysis demonstrated a significant increase in mortality of 0.38% per year (95% CI, 0.12-0.64%) in Massachusetts, attributable to a greater per-year decrease in mortality postreform in comparison states (-0.37%; 95% CI, -0.52% to -0.21%) compared with Massachusetts (0.01%; 95% CI, -0.20% to 0.11%).
  
  
  CONCLUSIONS
  Massachusetts healthcare reform increased the number of ICU patients with insurance but was not associated with significant changes in ICU use or discharge destination among ICU patients. Reform was also not associated with changed in-hospital mortality for ICU patients; however, this association was dependent on the comparison states chosen in the analysis.
authors.affiliation: 1Division of Pulmonary, Allergy and Critical Care, Hospital of the University of Pennsylvania, Philadelphia, PA. 2Department of Anesthesiology, Columbia University, New York, NY. 3Leonard Davis Institute of Health Economics, University of Pennsylvania, Philadelphia, PA. 4Center for Health Equity Research and Promotion, Philadelphia VA Medical Center, Philadelphia, PA. 5Division of Traumatology, Surgical Critical Care and Emergency Surgery, Department of Surgery, Hospital of the University of Pennsylvania, Philadelphia, PA. 6Center for Policy Research, Department of Emergency Medicine, Hospital of the University of Pennsylvania, Philadelphia, PA. 7CRISMA Center, Department of Critical Care Medicine, University of Pittsburgh, Pittsburgh, PA. 8Division of Pulmonary and Critical Care Medicine, University of Michigan, Ann Arbor, MI. 9Center for Healthcare Outcomes and Policy, University of Michigan, Ann Arbor, MI.
authors.forename: Sarah M
authors.initials: SM
authors.lastname: Lyon
authors.forename: Hannah
authors.initials: H
authors.lastname: Wunsch
authors.forename: David A
authors.initials: DA
authors.lastname: Asch
authors.forename: Brendan G
authors.initials: BG
authors.lastname: Carr
authors.forename: Jeremy M
authors.initials: JM
authors.lastname: Kahn
authors.forename: Colin R
authors.initials: CR
authors.lastname: Cooke
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D018166:Health Care Reform / Q000706:statistics & numerical data*; D017052:Hospital Mortality / Q000639:trends*; D006801:Humans; D019458:Insurance Coverage / Q000706:statistics & numerical data*; D007348:Insurance, Health / Q000706:statistics & numerical data*; D007362:Intensive Care Units / Q000706:statistics & numerical data*; D008297:Male; D008404:Massachusetts; D008875:Middle Aged; D010343:Patient Admission / Q000706:statistics & numerical data; D010351:Patient Discharge / Q000706:statistics & numerical data; D012959:Socioeconomic Factors; D055815:Young Adult