Is it better to cultivate positive affect or optimism? Predicting improvements in medical adherence following a positive psychology intervention in patients with acute coronary syndrome

Objective: Adherence to health behaviors following an acute coronary syndrome (ACS) is strongly associated with superior prognosis. Both optimism and positive affect may play important roles in such adherence. However, the relationship between changes in these constructs in the context of positive psychology interventions (PPIs) and adherence to health behaviors is not fully understood. Accordingly, we aimed to examine these relationships among a cohort of post-ACS patients receiving a PPI. Method: Post-ACS participants who received a PPI during a factorial trial (N=128) completed self-report measures of positive affect and optimism, along with the Medical Outcomes Study Specific Adherence Scale items for diet, physical activity, and medication adherence, over 16 weeks. The baseline and longitudinal effects of positive affect and optimism-representing changes in those constructs-on adherence were analyzed using mixed effects regression models. Results: Positive affect, but not optimism, was longitudinally associated with greater overall adherence to health behaviors (positive affect: beta=0.057, p=.006; optimism: beta=0.032, p=.36), with the effect driven by physical activity adherence (positive affect: beta=0.040, p=.004; optimism: beta=0.005, p=.83). Conclusion: Changes in positive affect may be more strongly associated with post-ACS adherence than optimism; this could have important implications for the development of PPIs to promote adherence.