Abstract 19882: The Effect of High Functional Aerobic Capacity on Cardiovascular Mortality in Patients With Diabetes Undergoing a Symptom-Limited Exercise Stress Test: A Long-Term Follow-up Study
Introduction: High Functional Aerobic Capacity (FAC) measured during symptom-limited treadmill ECG stress testing (TMET) has been associated with lower cardiovascular (CV) mortality, but little is known of this protective effect in people with diabetes mellitus (DM).
Hypothesis: We tested the hypothesis that a high FAC in patients with DM would have a similar CV mortality compared to patients without DM overall, regardless of coronary artery disease (CAD) history.
Methods: We conducted a longitudinal historical cohort study of consecutive patients with clinically indicated TMET from 1993 to 2006, and followed-up until 2015 using the National Death Index to ascertain survival status and cause of death. We examined the relationship between %FAC and CV mortality. %FAC was calculated as percent of age-sex achieved TMET time on the Bruce protocol and relative to the predicted time. We used Cox proportional hazard models that compared patients with DM at different levels of FAC and patients without DM regardless of FAC.
Results: The cohort included 43,637 patients, 69% male, mean age (SE) 54.3 (0.05) years, of which 3,268 had DM and 6,663 had CAD. After a median follow-up of 16.7 (0.01) years, 402 patients with DM and 1,751 without DM died of CV causes, unadjusted HR 3.03, 95% CI (2.72-3.38), p= <0.001. Mean %FAC was lower in patients with DM compared to those without DM [78.7(0.40) % vs 95.0 (0.11) % p=<0001]. Patients with DM and FAC ≥120% had similar CV mortality rates to all patients without DM. (See Table). In a model excluding those with CAD history, results were similar; HR 1.08, 95% CI (0.26-2.81), p=0.08. As FAC increased, CV mortality decreased; [HR 0.78, per each 10% increase in FAC, p=<0001].
Conclusion: Patients with DM and FAC ≥120% did not appear to be at increased CV mortality risk compared to patients without DM, regardless of CAD history. A high FAC may offset the increased risk for CV mortality attributed to DM, underscoring the importance of exercise as a protective lifestyle.
- Exercise tests and training
- Diabetes Mellitus
- Cardiovascular disease prevention
- Cardiorespiratory fitness
Author Disclosures: J.R. Medina-Inojosa: None. M. Jimenez Navarro: None. J. Rodriguez: None. V. Somers: None. A. Thomas: None. R. Squires: None. F. Lopez-Jimenez: None.
- © 2016 by American Heart Association, Inc.