Author + information
- Published online September 4, 2017.
- Joseph A. Ladapo, MD, PhD∗ (, )
- John M. Pfeifer, MD,
- Alana A. Choy-Shan, MD,
- James M. Pitcavage, MSPH and
- Brent A. Williams, PhD
- ↵∗David Geffen School of Medicine at UCLA, Department of Medicine, Division of General Internal Medicine and Health Services Research, 911 Broxton Avenue, 1st Floor, Los Angeles, California 90024
Approximately 4 million stable patients in the United States undergo cardiac stress testing or other imaging tests for suspected ischemic heart disease (IHD) each year (1). Despite wide recognition of the importance of patient-centered care and engagement, little is known about how the beliefs and preferences of patients influence management decisions. We sought to examine whether the beliefs and preferences of patients explain variations in follow-up management.
We surveyed adult patients (18 years or older) without diagnosed IHD who underwent initial evaluation for IHD with stress testing with imaging or coronary computed tomographic angiography (CTA) between November 1, 2013 and February 28, 2015 at Geisinger Health System (Mount Pocono, Pennsylvania). Geisinger’s institutional review board approved the study.
To assess the understanding of the initial test results of the patients, we asked, “What was the result of your stress test (or CTA)?” and, “From your understanding, was that a normal or abnormal result?” (normal or OK, abnormal or not OK, or don’t know). Patients were considered to understand their test result if there was concordance between the survey response of the patient and the test findings from the chart review. To assess the preferences of patients about their initial test, we asked, “How important did you think getting the stress test (or CTA) was for your health?” (not at all important, only a little bit important, somewhat important, very important, or don’t know). To assess the preferences of patients about follow-up care, we asked, “Thinking very generally about your health care, which of the following statements is the most true” (I always or almost always, usually, sometimes, or rarely get the follow-up care my doctor recommends). Patients were considered to have strong preferences for follow-up if they reported always and/or almost always completing recommended follow-up.
All analyses accounted for the effects of selection and nonresponse weights, and survey design, with stratification by initial test results and presence or absence of follow-up tests and/or procedures. We estimated logistic regression models to examine the association between receipt of follow-up tests and/or procedures and the beliefs and preferences of patients while controlling for sociodemographic and clinical variables. Analyses were performed using svy commands in Stata version 14.1 (StataCorp, College Station, Texas).
Of the 351 patients surveyed (of 604 contacted; participation rate: 58%), mean age was 57.4 years (interquartile range: 50 to 74 years), 48.8% were women, and 49.2% of parents completed no more than a high school education. The proportion of patients that reported experiencing angina before testing was 36.1%; of these patients, 38.0% reported that angina limited their daily activities.
Initial stress test or CTA results were positive in 10.6% (n = 115); 27.9% of patients did not feel their initial test was important for their health, 18.2% did not have an accurate understanding of their test result, and 38.2% did not have strong preferences for completing recommended follow-up.
Subsequent tests or procedures were performed in 11.8% of patients (4.6% after a normal test, 72.5% after an abnormal test). During follow-up, 3.0% of patients received additional noninvasive cardiac stress testing or CTA, 9.4% were referred for cardiac catheterization, and 3.3% underwent coronary revascularization. In adjusted analyses, patients who had an accurate understanding of their initial test result were less likely to undergo follow-up tests and/or procedures if the initial test was negative and more likely to undergo follow-up tests and/or procedures if the initial test was positive (Table 1). There was no significant association with patient beliefs about test importance or preferences for follow-up.
We found that, among patients with suspected IHD, patterns of subsequent testing and procedures were partially explained by whether patients understood their initial test result. To the best of our knowledge, this is the first study to assess the understanding of patients of stress test and/or CTA results, and their preferences about follow-up tests and/or procedures. Our study is not the first to demonstrate an inverse association between patient knowledge and intensity of care, although this was only found in patients with a negative initial test result (89% of the cohort).
Our study provides supportive evidence for policies designed to improve patient knowledge and literacy. For example, a provision of the Affordable Care Act affords funding for the development of patient decision aids in support of shared decision-making, and decision aid interventions often improve patient knowledge in addition to yielding other benefits.
Limitations include the fact that our study was single-center and retrospective, and errors or inaccuracies in self-reporting, including those related to discordant understanding and angina, could affect our results. CTA use was sparse, whereas stress echocardiography was predominant, and patients who participated in the survey might have differed substantially from patients who did not.
In conclusion, among patients with suspected IHD, patterns of subsequent testing and procedures were partially explained by whether patients understood their initial test result. Overall, follow-up test rates in this population were low, but policies to reduce variation in cardiovascular testing or minimize preference-sensitive tests and procedures may be enhanced by increasing patient knowledge.
The authors are grateful to the study participants for their contributions, and thank Jessica M. Runge for her help with data collection. Dr. Ladapo had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Please note: This research was funded by the National Heart, Lung, and Blood Institute (K23 HL116787; J.A. Ladapo, PI). The authors have reported that they have no relationships relevant to the contents of this paper to disclose.
- 2017 American College of Cardiology Foundation