WASHINGTON—What is the association between exercise capacity and the risk of major adverse cardiovascular events (MACEs)?

A study published in the journal Mayo Clinic Proceedings sought to determine that in veterans treated at two VAMCs—in the nation’s capital and Palo Alto, CA.1

The study, led by researchers from the DCVAMC and Georgetown University School of Medicine, both in Washington, and the Arnold School of Medicine at the University of South Carolina in Columbia, performed a symptom-limited exercise tolerance test to assess exercise capacity in 20,590 U.S. veterans. Among the participants were 12,975 blacks and 7,615 whites, averaging 58.2 years old.

None of the veterans had a history of MACE or evidence of ischemia at the time of or before their exercise tolerance test.

The researchers established quintiles of cardiorespiratory fitness (CRF) categories based on age-specific peak metabolic equivalents (METs) achieved. They also defined the age-specific MET level associated with no risk for MACE (hazard ratio [HR], 1.0) and formed four additional CRF categories based on METs achieved below—least fit and low fit—and above—moderately fit and highly fit—that level.

During follow-up of a median of 11.3 years, 2,846 veterans experienced MACEs. With the CRF-MACE association inverse and graded, the risk declined precipitously for those with a CRF level of 6.0 METs or higher.

When considering CFR categories based on the age-specific MET threshold, results indicate that the risk increased for those in the two CFR categories below that threshold, HR, 1.95 and HR 1.41, for the least-fit and low-fit individuals, respectively. At the same time, it decreased for those above it—HR, 0.77 and HR, 0.57, for moderately fit and highly fit, respectively.

“Increased CRF is inversely and independently associated with the risk for MACE,” study authors conclude. “When an age-specific MET threshold was defined, the risk for MACE increased significantly for those below that threshold and decreased for those above it.”

  1. Kokkinos PF, Faselis C, Myers J, Narayan P, Sui X, Zhang J, Lavie CJ, Moore H, Karasik P, Fletcher R. Cardiorespiratory Fitness and Incidence of Major Adverse Cardiovascular Events in US Veterans: A Cohort Study. Mayo Clin Proc. 2016 Nov 19. pii: S0025-6196(16)30587-0. doi: 10.1016/j.mayocp.2016.09.013. [Epub ahead of print] PubMed PMID: 27876315