Patterns, correlates, and prognostic significance of quality of life following breast cancer

OBJECTIVE: To describe quality of life (QOL) over a 12-month period among women with breast cancer, consider the association between QOL and overall survival (OS), and explore characteristics associated with QOL declines. METHODS: A population-based sample of Australian women (n=287) with invasive, unilateral breast cancer (Stage I+) was observed prospectively for a median of 6.6 years. QOL was assessed at 6, 12, and 18 months post-diagnosis, using the Functional Assessment of Cancer Therapy, Breast (FACT-B+4) questionnaire. Raw scores for the FACT-B+4 and subscales were computed and individuals were categorized according to whether QOL declined, remained stable or improved between 6 and 18 months. Kaplan-Meier and Cox proportional hazards survival methods were used to estimate OS and its associations with QOL. Logistic regression models identified factors associated with QOL decline. RESULTS: Within FACT-B+4 subscales, between 10% and 23% of women showed declines in QOL. Following adjustment for established prognostic factors, emotional well-being and FACT-B+4 scores at 6 months post-diagnosis were associated with OS (p<0.05). Declines in physical (p<0.01) or functional (p=0.02) well-being between 6 and 18 months post-diagnosis were also associated significantly with OS. Receiving multiple forms of adjuvant treatment, a perception of not handling stress well and reporting one or more other major life events at 6 months post-diagnosis were factors associated with declines in QOL in multivariable analyses. CONCLUSIONS: Interventions targeted at preventing QOL declines may ultimately improve quantity as well as quality of life following breast cancer.