Medical claims may not be enough to assess clinical outcomes in research trials

May 24, 2017 – According to DCRI researchers, while medical claims may be a reasonable resource to assess myocardial infarction (MI) and stroke outcomes, caution is still needed.

A recent study by DCRI researchers published May 24 in JAMA Cardiology found that one-year post-MI rates of recurrent MI, stroke and bleeding were lower when identified by medical claims than when adjudicated by physicians. The study also observed that the accuracy of medical claims in identifying events was, at best, modest for MI and stroke, using physician adjudication as gold standard, and lower for bleeding events.

“Pragmatic clinical trials have proposed use of readily-available data, such as patient medical claims, to assess clinical events, but the accuracy of billed diagnoses in identifying potential events is unclear,” said DCRI Fellow Patricia Guimaraes, MD, lead author of the study. According to Guimaraes, previous studies on the topic have all been limited to patients older than 65 years as they use data from Medicare.

“We wanted to take advantage of the TRANSLATE-ACS data–a study that included post-MI patients of all ages–and explore whether medical claims can accurately assess cardiovascular and bleeding events in an all-aged post-MI population,” Guimaraes said.

TRANSLATE-ACS, or Treatment with Adenosine Diphosphate Receptor Inhibitors: Longitudinal Assessment of Treatment Patterns and Events after Acute Coronary Syndrome, was an observational, longitudinal study led by the DCRI and the American College of Cardiology Foundation. It examined post-discharge care patterns and treatment adherence of 12,365 patients enrolled at 233 U.S. hospitals, and evaluated the safety, effectiveness, and healthcare costs of antiplatelet therapy use among contemporary acute MI patient populations treated with percutaneous coronary intervention.

For the JAMA study, DCRI researchers obtained medical claims data for all rehospitalizations occurring within a year of the index acute MI in patients enrolled in the TRANSLATE-ACS study. They identified recurrent MI, stroke, and bleeding events based on diagnosis and procedure codes in the acquired medical bills. These clinical events were independently signed off by physicians based on medical record review.

“Our results suggest that we need to be cautious about using medical claims as the only method of event ascertainment, especially for bleeding events,” Guimaraes said. “Medical claims have limited accuracy in identifying bleeding events, which suggests the need for an alternative approach to ensure good safety surveillance in cardiovascular studies.”

According to Guimaraes, to improve the accuracy of events collected through existing billing claims, the coding algorithms used to find events can be further developed.

“We can ensure a broad search for events as done in the TRANSLATE-ACS study and ascertain events through different methods to avoid missing or over/under-classifying events,” she said.

In addition to Guimaraes, other authors included Arun Krishnamoorthy, Lisa A. Kaltenbach, Kevin J. Anstrom, Mark B. Effron, Daniel B. Mark, Patrick L. McCollam, Linda Davidson-Ray, Eric D. Peterson and Tracy Y. Wang.