Temporal trends in the utilization of diagnostic testing and treatments for cardiovascular disease in the United States, 1993-2001

Background - Rates of invasive testing and treatment for coronary artery disease have increased over time. Less is known about trends in the utilization of noninvasive cardiac testing for coronary artery disease. The objective of this study was 2-fold: to explore temporal trends in the utilization of noninvasive and invasive cardiac services in relation to changes in the prevalence of cardiac disease, and to examine whether temporal increases have been targeted to potentially underserved populations. Methods and Results - We performed an annual cross-sectional population-based study of Medicare patients from 1993 to 2001. We identified stress testing, cardiac catheterization, and revascularization procedures, as well as hospitalizations for acute myocardial infarction, during each year and calculated population-based rates for each using the total fee-for-service Medicare population as the denominator and adjusting for age, gender, and race. We observed marked growth in the utilization rates of cardiac services over time, with relative rates nearly doubling for most services. Acute myocardial infarction hospitalization rates have remained stable over the study period. Although rates of all procedures except coronary artery bypass increased in all subgroups, differences in rates of cardiac testing and treatment between nonblack men and other subgroups persisted over time. Conclusions - Temporal increases in the use of noninvasive and invasive cardiac services are not explained by changes in disease prevalence and have not succeeded in narrowing preexisting treatment differences by gender and race. Such increases, although conferring benefit for some, may expose others to risk and cost without benefit.