Effect of physician specialty on use of necessary coronary angiography

Objectives. This study sought to determine whether having cardiologist as regular source of care influences likelihood of undergoing necessary coronary angiography. Background. An important element of the current health policy debate is the respective roles of primary care and specialist physicians. However, there are few dat on interspecialty differences in quality of care for patients with ischemic heart disease. Methods. We contacted 243 patients by telephone (response rate 72%) who had positive (or very positive) exercise stress test results and met additional clinical criteri for necessary coronary angiography. Study patients were randomly sampled from those undergoing exercise stress testing at one university and three public hospitals in Los Angeles between January 1, 1990 and June 30, 1991. Patients were asked whether they had regular source of care during the time after their exercise stress test and, if so, whether that provider was cardiologist or cardiology clinic. Results. Among survey responders, 47% underwent necessary coronary angiography within 3 months of exercise testing and 61% within 12 months. After adjustment for sociodemographics and clinical presentation, patients with cardiologist as regular source of care were more likely than all other patients to have undergone necessary angiography within 3 months (52% vs. 38%, p = 0.05) and within 12 months (74% vs. 44%, p = 0.0001) of the exercise test. At 3 months, there was trend toward more pronounced effect of ongoing cardiologic care within the public hospitals compared with the private hospital (p = 0.09 for interaction between hospital types). Conclusions. Patients with cardiologist as regular source of care were more likely than all other patients to undergo clinically necessary coronary angiography within both 3 and 12 months of exercise stress testing.