Purpose: To determine the effect of patient refusal on racial and sex differences in the use of coronary angiography and in outcomes among elderly patients with acute myocardial infarction.
Subjects and methods: We included Medicare beneficiary patients admitted to hospitals performing coronary angiography from February 1994 through July 1995. In-hospital use and refusal of coronary angiography were determined, and adjusted for patient, hospital, and physician characteristics.
Results: Of 124,691 patients, 53,671 (43%) underwent angiography during hospitalization and 2881 (2.3%) refused. Patients refusing angiography were more likely to be female (odds ratio [OR] = 1.37; 95% confidence interval [CI]: 1.23 to 1.53), black (OR = 1.26 vs. whites; 95% CI: 1.02 to 1.56), and older (OR = 2.25 per 10-year increase; 95% CI: 2.05 to 2.43) than patients who underwent angiography. Angiography use was lower in blacks (OR = 0.78; 95% CI: 0.72 to 0.83) than in whites, and lower in women (OR = 0.83; 95% CI: 0.80 to 0.86) than in men. Increased refusal explained 6% (95% CI: -3% to 15%) of the difference in angiography use between whites and blacks, and 16% (95% CI: 10% to 22%) of the difference between men and women. After adjustment for patient characteristics, refusal of angiography was not associated with worse survival at 1 year (OR = 0.99; 95% CI: 0.82 to 1.20).
Conclusion: Among Medicare beneficiaries, elderly female and black patients are more likely to refuse angiography than are male and white patients. However, patient refusal is uncommon and accounts for only a small fraction of the racial and sex differences in use of angiography after myocardial infarction.