Differences in the effect of patients' socioeconomic status on the use of invasive cardiovascular procedures across health insurance categories

OBJECTIVES: This study evaluated the effect of patients' socioeconomic status on use of coronary angiography, bypass grafting, and angioplasty across health insurance categories. METHODS: Multiple logistic regression was used to compute the odds of receiving each procedure among 206 233 ischemic heart disease patients residing in urban California zip codes from 1991 through 1993. RESULTS: Residents of high socioeconomic status areas were more likely (odds ratios [ORs] = 1.20-1.41) and residents of low socioeconomic status areas were less likely (ORs = 0.79-0.84) than residents of middle socioeconomic status areas to undergo each procedure. These effects were common among Medicare and health maintenance organization patients and uncommon for privately insured and uninsured patients. CONCLUSIONS: The effect of socioeconomic status varies across health insurance categories.