Prognostic value of exercise capacity among patients with treated depression: The Henry Ford Exercise Testing (FIT) Project

BackgroundExercise capacity is associated with survival in the general population. Whether this applies to patients with treated depression is not clear. HypothesisHigh exercise capacity remains associated with lower risk of all-cause mortality (ACM) and nonfatal myocardial infraction (MI) among patients with treated depression. MethodsWe included 5128 patients on antidepressant medications who completed a clinically indicated exercise stress test between 1991 and 2009. Patients were followed for a median duration of 9.4years for ACM and 4.5years for MI. Exercise capacity was estimated in metabolic equivalents of tasks (METs). Cox proportional hazards regression models were used. ResultsPatients with treated depression who achieved 12 METs (vs those achieving <6 METs) were younger (age 469 vs 61 +/- 12years), more often male (60% vs 23%), less often black (10% vs 27%), and less likely to be hypertensive (51% vs 86%), have DM (9% vs 38%), or be obese (11% vs 36%) or dyslipidemic (45% vs 54%). In the fully adjusted Cox proportional hazard regression model, exercise capacity was associated with a lower ACM (HR per 1-MET increase in exercise capacity: 0.82, 95% CI: 0.79-0.85, P<0.001) and nonfatal MI (HR: 0.92, 95% CI: 0.87-0.97, P=0.004). ConclusionsExercise capacity had an inverse association with both ACM and nonfatal MI in patients with treated depression, independent of cardiovascular risk factors. These results highlight the potential impact of assessing exercise capacity to identify risk, as well as promoting an active lifestyle among treated depression patients.