Physicians working in states that imposed damage caps for malpractice claims were less likely to perform invasive coronary angiography and percutaneous coronary intervention (PCI) than colleagues in no-cap states, according to a new study in JAMA Cardiology.
“These findings provide evidence that physicians who face lower malpractice risk tolerate greater clinical uncertainty in testing for and treating CAD (coronary artery disease),” wrote the researchers, led by Steven A. Farmer, MD, PhD, with George Washington University.
This is not necessarily a bad thing, the authors noted. Physicians may turn to “marginally beneficial” tests and treatments out of fear of malpractice liability—a strategy Farmer et al. termed “defensive medicine.” Imaging studies and invasive diagnostic tests are expensive examples of defensive medicine, and some experts feel they are overused.
“Because unrecognized CAD can have catastrophic outcomes, with missed acute myocardial infarction an important cause of malpractice lawsuits, physicians are understandably cautious in their testing and intervention decisions,” the researchers wrote.
In this study, Farmer and colleagues examined the behavior of 36,647 physicians in nine states that implemented malpractice damage caps between 2002 and 2005, and compared their willingness to perform tests and interventions for CAD to more than 39,000 clinicians in states without malpractice caps. These caps substantially reduced the amount of money a plaintiff could collect in a malpractice suit.
Physicians operating with lower malpractice risk were 24 percent less likely to use angiography as a first diagnostic test and were 7.8 percent more likely to use noninvasive stress testing. They were also 21 percent less likely to order a subsequent angiography after stress testing and were 23 percent less likely to perform revascularization—with fewer PCIs being the primary driver of that trend.
“Physicians substantially altered their approach to coronary artery disease testing and follow-up after initial ischemic evaluations following adoption of damage caps,” Farmer et al. wrote. “They performed a similar number of ischemic evaluations but conducted fewer initial left heart catheterizations, referred fewer stress-tested patients for left heart catheterizations, and referred fewer patients for revascularization.”
The authors noted the precap referral rates were similar between the groups, suggesting the policy change had a direct impact. This could have implications as hospitals and payers try to limit unnecessary procedures to align with new value-based payment models, they said.
“A core issue for these models is provider resistance to changing established practice patterns,” Farmer and colleagues wrote. “Our study suggests that physicians who face lower malpractice risk may be less concerned with that risk, and thus more receptive to new care delivery strategies associated with alternate payment models.”
One limitation of the study is it only included Medicare fee-for-service patients 65 and older. Physicians may make different referral decisions for younger patients or those on different insurance plans, the authors noted.