Objectives: To determine the relationship between depression scores and (1) anginal indices during exercise including time to onset of angina, duration of angina, and severity of angina and (2) beta-endorphin at rest and in response to exercise.
Design: Prospective clinical trial.
Setting: Tertiary-care university hospital.
Patients: Fifty-eight patients with documented coronary artery disease and exercise-induced ischemia.
Outcome measures: Anginal indices during exercise (time to onset of angina, duration of angina, severity of angina); hemodynamic measures (systolic blood pressure, heart rate, rate pressure product) at rest, at onset of angina and at peak exercise; and plasma beta-endorphin levels at rest and immediately after exercise.
Results: Twenty-two of 58 patients had typical angina and electrocardiographic change indicating myocardial ischemia during exercise. There was a positive correlation between depression scores and duration of angina and a negative correlation between depression scores and time to onset of angina. Among patients with angina during exercise, systolic blood pressure increased to a greater extent in patients with high depression scores. Patients with high depression scores had higher resting beta-endorphin levels.
Conclusions: Patients with depressed mood had greater perception of anginal pain than nondepressed patients, which cannot be explained by differences in the severity of ischemia. Possible mechanisms include an alteration in beta-endorphin regulation or differences in baroreceptor stimulation.