Whittle J, Conigliaro J, Good CB, Joswiak M.
Do patient preferences contribute to racial differences in cardiovascular procedure use?
J Gen Int Med 1997;12(5):267-73.

A frequently given potential explanation for the repeated findings of lower rates of coronary revascularization procedures among blacks in comparison to whites is “patient choice” – specifically, the higher relative rate of black refusal to accept physician recommendations, presumably due to race-determined beliefs, uncertainties or suspicions. This study is important because it is one of the very few that explores whether race-linked beliefs (or other variables) are in fact the significant predictors of patient refusal.

Whittle et al. conducted a cross-sectional survey to determine whether patient preferences for the use of revascularization differ between black and white male patients treated at the Pittsburgh VA Medical center. The survey included questions on the patient’s age, race, educational level, employment status, living arrangements, health status, and familiarity with revascularization. The familiarity variable was measured by “asking participants to report how many family members or friends had undergone coronary artery bypass grafting (CABG), their own estimate of operative mortality of CABG, and their self-reported familiarity with CABG.”

The univariate comparison indicated that whites were more likely to agree to undergo procedures than their black counterparts. For example, when coronary artery angioplasty (PTCA) was recommended, 52% of blacks answered positively compared to 70% of whites. When CABG was the recommended procedure, 65% of blacks and 76% of whites agreed with the recommendation. However, when race was “forced into other [multivariate] models, it did not approach statistical significance.” Rather, measures of familiarity with the procedure were the “most important predictors of attitude toward revascularization.” The question with the strongest predictive value considered the respondent’s ability to estimate the risk of the procedure in question (black/white odds ratio for CABG was 3.79, 95% CI: 2.5-6.30; odds ratio for PTCA was 2.52, 95% CI: 1.37-4.77.) Thus, “much of the black-white difference in patient preferences seemed to be explained by questions that addressed familiarity with the procedure.” The racial differences in preference also differed when race of the interviewer was factored in as a variable. Black patients were considerably more likely to accept recommendations for angioplasty and CABG when the interviewer was black; whereas, the race of the interviewer had no effect on white patients’ responses. When the interviewer was black, the differences in the responses of blacks and whites were smaller.

This study has significant implications for physician-patient communication and for physician and patient education. The investigators conclude that “clinicians should be careful to assess baseline levels of familiarity with procedures when discussing recommendations with patients.” The need for clinician awareness regarding the potential for race-related trust issues was also demonstrated.

There are three noteworthy limitations of this study. First, the scenarios presented to the patients were hypothetical and, as the authors suggest, “actual decision making, for example in the setting of an acute ischemic event, might be considerably different as this situation would presumably lead to marked changes in one’s perceived susceptibility to disease, as well as its seriousness.” Second, a “convenience” sample was used as opposed to a true random sample. The patients interviewed were those arriving early for their scheduled appointment who therefore had the time to be interviewed. This may well be an unrepresentative sample of the population. Third, the study did not address “whether increasing familiarity with the procedures would have led to changes in attitudes.”