Association of optimism and social support with health-related quality of life among Australian women cancer survivors – A cohort study

Aim: Large-scale studies investigating health-related quality of life (HRQL) in cancer survivors are limited. This study aims to investigate HRQL and its relation to optimism and social support among Australian women following a cancer diagnosis. Methods: Data were from the Australian Longitudinal Study on Women's Health, a large cohort study (n = 14,715; born 1946-51), with 1428 incident cancer cases ascertained 1996-2017 via linkage to the Australian Cancer Database. HRQL was measured using the Short Form-36 (median 1.7 years post-cancer-diagnosis). Multivariable linear regression was performed on each HRQL domain, separately for all cancers combined, major cancer sites, and cancer-free peers. Results: Higher optimism and social support were significantly associated with better HRQL across various domains in women with and without a cancer diagnosis (p < 0.05). Mean HRQL scores across all domains for all cancer sites were significantly higher among optimistic versus not optimistic women with cancer (p < 0.05). Adjusting for sociodemographic and other health conditions, lower optimism was associated with reduced scores across all domains, with greater reductions in mental health (adjusted mean difference (AMD) = -11.54, p < 0.01) followed by general health (AMD = -11.08, p < 0.01). Social support was less consistently related to HRQL scores, and following adjustment was only significantly associated with social functioning (AMD = -7.22, p < 0.01) and mental health (AMD = -6.34, p < 0.01). Conclusions: Our findings highlight a strong connection between optimism, social support, and HRQL among cancer survivors. Providing psychosocial support and addressing behavioral and socioeconomic factors and other health conditions associated with optimism and social support may improve HRQL.