title: Impact of Expanded Insurance Coverage on Racial Disparities in Vascular Disease: Insights From Massachusetts.
abstract: OBJECTIVE
  To evaluate the impact of health insurance expansion on racial disparities in severity of peripheral arterial disease.
  
  
  BACKGROUND
  Lack of insurance and non-white race are associated with increased severity, increased amputation rates, and decreased revascularization rates in patients with peripheral artery disease (PAD). Little is known about how expanded insurance coverage affects disparities in presentation with and management of PAD. The 2006 Massachusetts health reform expanded coverage to 98% of residents and provided the framework for the Affordable Care Act.
  
  
  METHODS
  We conducted a retrospective cohort study of nonelderly, white and non-white patients admitted with PAD in Massachusetts (MA) and 4 control states. Risk-adjusted difference-in-differences models were used to evaluate changes in probability of presenting with severe disease. Multivariable linear regression models were used to evaluate disparities in disease severity before and after the 2006 health insurance expansion.
  
  
  RESULTS
  Before the 2006 MA insurance expansion, non-white patients in both MA and control states had a 12 to 13 percentage-point higher probability of presenting with severe disease (P < 0.001) than white patients. After the expansion, measured disparities in disease severity by patient race were no longer statistically significant in Massachusetts (+3.0 percentage-point difference, P = 0.385) whereas disparities persisted in control states (+10.0 percentage-point difference, P < 0.001). Overall, non-white patients in MA had an 11.2 percentage-point decreased probability of severe PAD (P = 0.042) relative to concurrent trends in control states.
  
  
  CONCLUSIONS
  The 2006 Massachusetts insurance expansion was associated with a decreased probability of patients presenting with severe PAD and resolution of measured racial disparities in severe PAD in MA.
authors.affiliation: *Department of Surgery, Massachusetts General Hospital, Boston, MA †Department of Medicine, Massachusetts General Hospital, Boston, MA ‡National Bureau of Economic Research, Cambridge, MA.
authors.forename: Andrew P
authors.initials: AP
authors.lastname: Loehrer
authors.forename: Alexander T
authors.initials: AT
authors.lastname: Hawkins
authors.forename: Hugh G
authors.initials: HG
authors.lastname: Auchincloss
authors.forename: Zirui
authors.initials: Z
authors.lastname: Song
authors.forename: Matthew M
authors.initials: MM
authors.lastname: Hutter
authors.forename: Virendra I
authors.initials: VI
authors.lastname: Patel
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D016208:Databases, Factual; D018166:Health Care Reform; D006297:Health Services Accessibility / Q000191:economics* / Q000706:statistics & numerical data; D054624:Health Status Disparities; D054625:Healthcare Disparities / Q000191:economics / Q000208:ethnology* / Q000706:statistics & numerical data; D006801:Humans; D019458:Insurance Coverage / Q000331:legislation & jurisprudence* / Q000706:statistics & numerical data; D007348:Insurance, Health / Q000331:legislation & jurisprudence* / Q000706:statistics & numerical data; D016014:Linear Models; D008404:Massachusetts / Q000453:epidemiology; D008875:Middle Aged; D015999:Multivariate Analysis; D058991:Patient Protection and Affordable Care Act; D058729:Peripheral Arterial Disease / Q000191:economics / Q000208:ethnology* / Q000628:therapy; D012189:Retrospective Studies; D020379:Risk Adjustment; D012720:Severity of Illness Index; D055815:Young Adult