Ethnicity and determinants of quality of life after prostate cancer treatment.

OBJECTIVES: To examine the quality of life (QOL) in a sample of men recently treated for localized prostate cancer to determine whether minority men are at greater risk of decrements in QOL and to identify factors that might explain disparities in QOL outcomes.
METHODS: The relationship between ethnicity and QOL was evaluated in a diverse sample of 204 men (85 non-Hispanic white, 37 African-American, and 82 Hispanic men). We also assessed associations with other factors known to be related to QOL (ie, sociodemographic, medical, and health behavior factors). Hierarchical regression analysis was used to assess the relationship between ethnicity and QOL. Factors that were anticipated to explain the ethnic differences in QOL were then added in stepwise analyses.
RESULTS: Ethnic group membership was related to QOL such that minority men had lower QOL than non-Hispanic white men. In subsequent steps, the association between ethnic group membership and QOL was partially mediated by sociodemographic, medical, and health behavior factors, with each factor adding significant incremental variance (5%, 5%, and 17%, respectively). Three variables remained significant in the final model, which explained 37% of the variance in QOL scores: medical comorbidity, physical activity, and sleep functioning.
CONCLUSIONS: Health behaviors appear to be strongly related to men's QOL after prostate cancer treatment. Intervention studies aimed at improving QOL should include a brief assessment of health behaviors and may want to incorporate intervention components designed to address physical activity and sleep functioning.