Background: Although the deleterious impact of psychological distress on patients with coronary heart disease (CHD) is recognized, few studies have examined the influence of change in psychological distress on health outcomes over time. This study investigated whether three common manifestations of distress (depression, anxiety, and perceived stress) and their changes predicted the decline in physical functioning in CHD patients over 12 months. In addition, perceived social support was examined as a buffer of psychological distress or a direct predictor of physical functioning.
Methods: Participants were 255 CHD patients with a mean age of 63 (SD = 8.65) years, including 208 men and 47 women. Psychological distress and physical functioning were assessed at baseline, 6 months and 12 months. Hierarchical regression analyses were conducted to examine the influences of psychological factors on physical functioning over 12 months. All models were adjusted for baseline physical functioning, age, gender, marital status, education, BMI, and length of participation at a wellness center.
Results: For each psychological distress variable (depression, anxiety, or perceived stress), both the baseline (βs = - 0.19 to - 0.32, ps = 0.008 to < 0.001) and its respective change over time (βs = - 0.17 to - 0.38, ps = 0.020 to < 0.001) independently and significantly predicted greater decline in physical functioning at 6 and 12 months, after adjusting for covariates. Perceived social support predicted greater improvement in physical functioning at 12 months (β = 0.13, p = 0.050), but it did not buffer impact of psychological distress.
Conclusions: Findings underscore the importance of monitoring various forms of psychological distress continuously over time for CHD patients.
Keywords: Anxiety; Coronary heart disease; Depression; Perceived social support; Perceived stress; Physical functioning.