ROME (FRONTLINE MEDICAL NEWS) – Cardiorespiratory fitness provided strong and graded protection against all-cause mortality and nonfatal MI in a study of more than 5,000 patients treated for depression, Amjad M. Ahmed, MD, reported at the annual congress of the European Society of Cardiology.

“These results highlight the importance of assessing fitness to identify risk as well as promoting an active lifestyle in patients with depression,” said Dr. Ahmed of Abdulaziz University for Health Sciences in Riyadh, Saudi Arabia.

He presented a retrospective analysis of participants in the Henry Ford Exercise Testing (FIT) Project. The project included 69,885 consecutive physician-referred patients who underwent Bruce protocol treadmill exercise testing during 1991-2009, making this the largest study of physical fitness to date. Participants were then followed for a median of 11.5 years.

This analysis focused on the 5,128 subjects who were on antidepressant medication at the time of their treadmill test. Their baseline cardiorespiratory fitness, as estimated by achieved peak metabolic equivalents (METs) on the treadmill, varied inversely with their risks of acute MI and all-cause mortality in the years to come. However, the less fit a patient was, the greater the burden of traditional cardiovascular risk factors. For example, the prevalence of hypertension was 86% in patients who achieved fewer than 6 METs, 75% in those who achieved 6-9 METs, 62% in depressed patients who reached 10-11 METs, and 51% in those who achieved 12 METs or more.

For this reason, Dr. Ahmed and coinvestigators performed a Cox multivariate regression analysis adjusted extensively for potential confounders, including age, sex, race, cardiovascular risk factors, known coronary artery disease, the use of cardiovascular medications, and the reason for the referral for stress testing.

When an achieved MET below 6 was used as the reference standard, for every 1 MET above 6 that patients achieved, their adjusted risk of all-cause mortality decreased by 18%, and the risk of nonfatal MI fell by 8%.

Session cochair Martin Halle, MD , pointed out what he viewed as a major limitation of the study.

“You didn’t follow their physical fitness over time, so you can’t say that increasing their METs would bring a better prognosis,” said Dr. Halle, professor and chairman of the department of preventive and rehabilitative sports medicine at the Technical University of Munich.

Dr. Ahmed reported having no financial conflicts of interest related to the Henry Ford FIT Project.