When exercise tests are used to assess a patient’s heart health, it’s important to consider a patient’s sex, according to a recent study that found sex-specific risk scores help better identify patients at increased risk for death.
Published in JAMA Cardiology, this study questioned the accuracy of standard risk scores in estimating mortality risk-based exercise stress tests.
According to authors, exercise testing is recommended to assess the health of patients with known or suspected heart disease. During stress tests, patients exercise on a bike or treadmill to help doctors see how their heart responds to added workload. The results are very telling, as limited exercise capability and poor results are associated with poorer outcomes and prognosis. However, experts worry that current risk scores used to interpret stress test results may be outdated, as they don’t consider sex in their calculations.
To test the accuracy of risk scores, experts conducted a study with two large cohorts from the Cleveland Clinic Foundation and Henry Ford Hospital. Together, these cohorts included more than 109,000 adults who underwent exercise testing between 1991 and 2013. Researchers collected information on patients’ health and lifestyle upon enrollment and tracked key outcomes, including death, for roughly 7–10 years.
Their goal was to compare three different calculations of mortality risk—the Duke Treadmill Score, the Lauer nomogram and a new, sex-specific calculation developed for this study. The first two scores have been widely used to predict mortality risk based on exercise testing, but were developed largely in male populations. However, the new score builds upon past calculations, while accounting for sex-related differences known to affect health and outcomes.
Not surprisingly, researchers found that the sex-specific calculation was more accurate in predicting mortality risk than the standard score. After analysis, the sex-specific risk score helped accurately predict mortality risk in 79% of women and 81% in men. In comparison, the Duke Treadmill score and Lauer nomogram were only 70–75% accurate. Authors also note that the sex-specific score helped better identify patients with high mortality risk than the other two scores.
Based on findings, authors conclude that their new sex-specific risk calculations outperform traditional risk scores used with exercise stress tests. They have made their sex-specific risk calculator readily available online for both patients and providers. Authors hope that the online calculator will be used to assess prognosis and emphasize the importance of exercise for heart health.