Lifestyle Patterns and Sleep Disturbance Among Black Breast Cancer Survivors: Results from the Women's Circle of Health Follow-Up Study.

BACKGROUND: African American/Black breast cancer (BC) survivors experience higher rates of sleep disturbance than their White counterparts, which may contribute to worse survival and quality of life; however, whether adherence to cancer-related lifestyle guidelines (adiposity, physical activity, and diet) is associated with post-diagnosis sleep disturbance in Black women remains unexplored. We evaluated whether adherence to World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) recommendations was associated with lower risk of sleep disturbance in a population-based cohort of Black BC survivors, the Women's Circle of Health Follow-Up Study. METHODS: Pre-diagnosis lifestyle factors were assessed during home visits among 682 participants. Lifestyle pattern scores were calculated using the WCRF/AICR scoring system (range: 0-7; higher scores indicating greater adherence). Sleep disturbance was assessed ∼2 years post-diagnosis using the Pittsburgh Sleep Quality Index, with a score >5 indicating sleep disturbance. Robust Poisson regression estimated relative risks (RRs) and 95% confidence intervals (CIs) for associations between lifestyle pattern scores and sleep disturbance. RESULTS: The mean (SD) pre-diagnosis lifestyle pattern score was 3.0 (1.1), and 59.8% of survivors had post-diagnosis sleep disturbance. Compared with women in the lowest quartile of lifestyle pattern score (0-2.25), those in the highest quartile (≥4) had a 21% lower risk of sleep disturbance (RR = 0.79, 95% CI: 0.65, 0.97) after multivariable adjustment. Higher lifestyle pattern scores were associated with better domain scores for subjective sleep quality, sleep disturbance, and daytime dysfunction. CONCLUSION: Adherence to cancer-related lifestyle guidelines may reduce the risk of sleep disturbance among Black BC survivors.