Higher cortisol predicts less improvement in verbal memory performance after cardiac rehabilitation in patients with coronary artery disease

Objective. While physical activity can improve verbal memory performance in subjects with coronary artery disease (CAD), there is large variability in response. Elevated cortisol production has been suggested to negatively affect verbal memory performance, yet cortisol concentrations have not been assessed as a predictor of response to exercise intervention in those with CAD. Methods. CAD patients participating in a one-year cardiac rehabilitation program were recruited. Memory was assessed with the California Verbal Learning Test second edition at baseline and one year. Cortisol was measured from a 20 mg, 3.0 cm hair sample collected at baseline. Results. In patients with CAD (n = 56, mean ± SD age = 66 ± 11, 86% male), higher cortisol (hair cortisol concentrations ≥ 153.2 ng/g) significantly predicted less memory improvement (F 1, 50 = 5.50, P = 0.02) when controlling for age (F 1, 50 = 0.17, P = 0.68), gender (F 1, 50 = 2.51, P = 0.12), maximal oxygen uptake (F 1, 50 = 1.88, P = 0.18), and body mass index (F 1, 50 = 3.25, P = 0.08). Conclusion. Prolonged hypothalamic pituitary adrenal axis activation may interfere with exercise-related improvements in memory in CAD.