Effects of Comedy on the Health-Related Quality of Life of Cancer Survivors and Its Associations With the Big Five Personality Traits: A Post Hoc Analysis.

Introduction: This study is a post hoc analysis of a single-arm trial to determine whether daily viewing of comedy videos for four weeks improves health-related quality of life (HRQOL) and oxidative stress in cancer survivors (UMIN-CTR 000044880). There are no reports of personality traits affecting HRQOL improvement. The purpose of this post hoc analysis was to identify associations with personality traits that may improve HRQOL.

Methodology: This analysis compared the baseline scores on the Ten-Item Personality Inventory-Japanese version (TIPI-J) for personality traits in Functional Assessment of Cancer Therapy-G (FACT-G) groups with improved or worsened scores. This grouping was based on the results of previous studies. In addition, the EuroQOL 5 dimension 3 level (EQ-5D-3L), Hospital Anxiety and Depression Scale (HADS) score, biological antioxidant potential (BAP), reactive oxygen metabolite-derived compounds, oxidative stress index, and potential antioxidant potential were assessed for each group. Items related to oxidative stress were tested using t-tests, while other items were tested using Friedman's analysis of variance.

Results: Forty-three participants completed the analysis (FACT-G improved [up group], = 25; FACT-G decreased [down group], = 18). No significant differences in the TIPI-J items existed between the two groups. Significant items for oxidative stress in the FACT-G up group were BAP (= 0.04, Cohen's = 0.32) and potential antioxidant capacity (= 0.02, Cohen's = 0.41). In the FACT-G down group, the significant item was potential antioxidant capacity ( = 0.03, Cohen's​​​​​​​ = 0.46). The FACT-G up group had significant changes over time in the scores of the EuroQOL Visual Analog Scale (EQ-VAS;  = 21.151 [df = 4]; < 0.01), HADS-anxiety (χ = 24.579 [df = 4]; < 0.01), and HADS-depression (χ = 29.068 [df = 4]; < 0.01).

Conclusions: Our results suggested that cancer survivors' personality traits did not influence the effects of viewing comedy. It has been suggested that the group with increased FACT-G may have had an improvement in the EQ-VAS, HADS, and potential antioxidant capacity independent of FACT-G.