Psychological risk factors may moderate pharmacological treatment effects among ischemic heart disease patients. Canadian Amlodipine/Atenolol in Silent Ischemia Study (CASIS) Investigators.

BACKGROUND

Numerous research findings support the proposed connection between such psychological characteristics as stress and hostility and the manifestation of disease. However, less evidence is available concerning the role(s) psychological factors might play in the process of disease recovery.

METHODS

Eighty patients with known coronary disease and exercise-induced ischemia underwent treadmill exercise testing and 48-hour ambulatory electrocardiographic monitoring and completed a battery of standardized psychological tests assessing hostility, depression, and daily stress on four occasions during a 12-week pharmacological treatment study. After withdrawal of antiischemic drugs at baseline, patients returned for subsequent tests at 3-week intervals. During the second and third intervals, patients were prescribed one of two antiischemic medications, atenolol or amlodipine, or given a placebo. All patients were then placed on a combination treatment protocol for the 3 weeks before the final testing date.

RESULTS

The combination treatment produced highly significant benefits across all measured cardiac variables (20.3% improvement in exercise performance, 13% reduction in reported angina, 64.0% reduction in the frequency of ischemic episodes; for all, p < .01). However, results showed that high baseline levels of daily stress were associated with reliably smaller treatment effects on measures of ischemia frequency and treadmill exercise time and with a significantly greater likelihood of reporting angina after treatment (r = -0.24, -0.25, and -0.33, respectively; p <.05). In addition, high baseline hostility predicted significantly smaller diastolic blood pressure improvements (r = -0.29, p < .05).

CONCLUSIONS

These results indicate that psychological risk factors may have globally negative effects on the course of treatment and suggest particular factors that may warrant attention in trials targeting cardiac symptom reduction.