Effects of acute mental stress and exercise on inflammatory markers in patients with coronary artery disease and healthy controls

Abstract

Physical and mental stressors result in increased inflammation markers in populations free of coronary artery disease (CAD). However, inflammatory responses to mental and exercise challenges have not been established in patients with CAD. This study investigated the responses of inflammatory markers, including C-reactive protein (CRP), interleukin-6 (IL-6), and soluble intercellular adhesion molecule-1, in patients with CAD after successful elective percutaneous coronary intervention (n = 36, 59 +/- 8 years of age, 33% women) and healthy controls without a history of CAD (n = 28, 54 +/- 10 years of age, 36% women). Increases in inflammatory markers were examined in response to mental challenge tasks (anger recall and mental arithmetic) and treadmill exercise. Stress echocardiography was used to rule out stress-induced ischemia as a possible confounding factor. Results showed that CRP increased significantly to mental challenge and exercise (p values <0.01), and CRP responses were higher in patients with CAD than in controls (change in mental arithmetic 0.19 +/- 0.11 vs 0.01 +/- 0.03 mg/L, p = 0.003; change in exercise 0.57 +/- 0.11 vs 0.08 +/- 0.0.03 mg/L, p = 0.001). Increased norepinephrine responses were related to larger CRP and IL-6 increases to mental challenge tasks (p values <0.05). Exercise elicited increased CRP, IL-6, and soluble intercellular adhesion molecule-1 levels (p values <0.01), and these responses were larger than with mental challenge tasks (p values <0.05). In conclusion, mental stress and exercise induce increased levels of inflammatory markers in patients with CAD. These stress-induced increases are larger than in healthy subjects, occur in the absence of myocardial ischemia, and are related to the neurohormonal stress response.