DEVELOPMENT OF HEALTH-RELATED QUALITY OF LIFE FOLLOWING PROSTATE CANCER DIAGNOSIS IS ASSOCIATED WITH OPTIMISM AND SELF-EFFICACY

Purpose: Side-effects from prostate cancer (Pca) treatments are known to cause a decrease in patients’ health-related quality of life (HRQoL). Post treatment HRQoL levels are often compared to a pre-treatment baseline, though measured after diagnosis. The impact of Pca diagnosis on HRQoL has received less attention. Therefore, to investigate the consequence of Pca diagnosis on patients’ HRQoL and the association between HRQoL and personality traits, we surveyed patients before and after Pca diagnosis. Our hypothesis was that the decline in HRQoL, assumed to be caused by treatment side-effects, would already start after Pca diagnosis, rather than after treatment. Moreover, we hypothesized that personality traits are associated to the impact of Pca diagnosis on HRQoL.

Method(s): Prospective study in ten Dutch hospitals recruiting patients scheduled for prostate biopsy (N=388), from which 126 patients were later diagnosed with Pca and 262 patients served as control group without Pca. Questionnaires were filled out at biopsy (T0, N=377, response rate 97.2%) and after diagnosis, but before treatment was started (T1, N=80, response rate 63.5%). Measures included personality traits (big five, optimism, self-efficacy) and HRQoL (EORTC QLQ-C30 and prostate specific PR25-module). Analyses were performed using T-tests, ANOVA and Pearson correlations.

Result(s): At biopsy no difference was observed in HRQoL between patients later diagnosed with Pca and the control group without Pca. In Pca patients HRQoL then declined following diagnosis. Optimism was positively related to the Global health subscale at T0 (r(338)=.307, p<.001), but not anymore at T1. At T1 only self-efficacy was correlated with Global health (r(67)=.256, p=.03). The largest decline in HRQoL following Pca diagnosis was found on the role functioning subscale. 

Conclusion(s): We found evidence that the decline of HRQoL in Pca patients already starts after diagnosis rather than after treatment. In an uncertain situation like prostate biopsy, optimism seems to affect HRQoL. However, after diagnosis we found patients’ self-efficacy to be positively correlated with HRQoL. This may indicate that if a patient believes he is able to do what is needed given his situation, HRQoL is higher. Assumed no major changes have occured in patients’ physical condition in the period around Pca diagnosis, the observed decline in HRQoL may have a psycho-social cause. Interventions to improve self-efficacy in Pca patients following diagnosis could be useful.