Not All Insurance Is Equal: Differential Treatment and Health Outcomes by Insurance Coverage Among Nonelderly Adult Patients With Heart Attack

BACKGROUND: The Affordable Care Act has provided health insurance to a large portion of the uninsured in the United States. However, different types of health insurance provide varying amounts of reimbursements to providers, which may lead to different types of treatment, potentially worsening health outcomes in patients covered by low‐reimbursement insurance plans, such as Medicaid. The objective was to determine differences in access, treatment, and health outcomes by insurance type, using hospital fixed effects. METHODS AND RESULTS: We conducted a multivariate regression analysis using patient‐level data for nonelderly adult patients with acute myocardial infarction in California from January 1, 2001, to December 31, 2014, as well as hospital‐level information to control for differences between hospitals. The probability of Medicaid‐insured and uninsured patients having access to catheterization laboratory was higher by 4.50 and 3.75 percentage points, respectively, relative to privately insured patients. When controlling for access to percutaneous coronary intervention facilities, however, Medicaid‐insured and uninsured patients had a 4.24– and 0.85–percentage point lower probability, respectively, in receiving percutaneous coronary intervention treatment compared with privately insured patients. They also had higher mortality and readmission rates relative to privately insured patients. CONCLUSIONS: Although Medicaid‐insured and uninsured patients with acute myocardial infarction had better access to catheterization laboratories, they had significantly lower probabilities of receiving percutaneous coronary intervention treatment and a higher likelihood of death and readmission compared with privately insured patients. This provides empirical evidence that treatment received and health outcomes strongly vary between Medicaid‐insured, uninsured, and privately insured patients, with Medicaid‐insured patients most disproportionately affected, despite having better access to cardiac technology.