The longitudinal association of optimism with quality of life after percutaneous coronary intervention for coronary heart disease; The THORESCI study

BACKGROUND: Positive psychological factors such as optimism are predictive of favorable clinical outcomes in patients with cardiac disease. Evidence suggests that trait optimism can vary over time, especially after a coronary event. We therefore examined whether the level and change in optimism across the one-year time period after percutaneous coronary intervention (PCI) were associated with changes in quality of life (QoL) over time. The analyses were adjusted for negative psychological functioning and health behavior adherence as potential explanatory factors.

METHODS: Patients who underwent PCI (n = 1759, 21 % female, mean age = 64 ± 10 years) filled out a psychological survey including positive (optimism; LOT-R) and negative psychological factors (depression (PHQ9) and anxiety (GAD7)), QoL (WHOQOL-BREF), and health behavior adherence (MOS-GAS) at inclusion and one year later (n = 1474). Data were analyzed using hierarchical linear mixed modeling with time-varying predictors and covariates.

RESULTS: Optimism levels increased from baseline (Mean BL = 7.6 (SD = 2.1) to 1-year follow-up in 43 % of the patients, whereas optimism decreased in 36 %; r intraclass = 0.53). Optimism was associated with a higher level of overall QoL (B = 1.96, se = 0.09, p < .001) and more positive 1-year change in QoL (B = 0.55, se = 0.09, p < .001), adjusting for demographic and clinical covariates, with similar findings for all subdomains. Adding depression and anxiety (both significant negatively correlated with of QoL) explained part of the associations of optimism with physical, psychological and environmental QoL, but not with social QoL. Health behavior adherence was significantly correlated with most QoL components, but adherence did not affect the association between optimism and QoL.

CONCLUSION: These data indicate marked individual differences in the magnitude of changes in optimism following PCI. Both higher levels and increases in optimism were associated with higher and improving QoL. Depression and anxiety, but not health behavior adherence, explained part of this relationship. Optimism might be an important psychological factor to address in cardiac rehabilitation.