Prevalence, risk factors, and trajectories of sleep disturbance in a cohort of African-American breast cancer survivors.

PURPOSE: Sleep disturbance may be an overlooked modifiable risk factor for health disparities among African-American breast cancer survivors (AABCS). This study aimed to identify the prevalence of and risk factors for sleep disturbance in a cohort of AABCS.
METHODS: The study was conducted among participants in the Women's Circle of Health Follow-up Study, a longitudinal study of breast cancer in 10 counties in New Jersey. Cases were identified shortly after diagnosis by the New Jersey State Cancer Registry. Self-reported sleep disturbance (Pittsburgh Sleep Quality Index) and other factors (e.g., socioeconomic status, menopausal status) were assessed at pre-diagnosis (n = 637), 10 months post-diagnosis (n = 261), and 24 months post-diagnosis (n = 632). Clinical data were obtained via medical record abstraction, and height and weight were measured by study staff.
RESULTS: Most AABCS (57%) reported clinically significant sleep disturbance before diagnosis, and this rate remained largely unchanged at 10 months (53%) and 24 months post-diagnosis (61%). Average sleep disturbance scores indicated clinically significant disturbance at all three assessments (M range = 6.67-7.57). Most reported sleeping fewer than the recommended 7 hours per night at each assessment (range 57-65%). Risk factors for sleep disturbance were identified at each assessment, including pre-diagnosis (less education), 10 months post-diagnosis (lack of insurance, treatment with chemotherapy), and 24 months post-diagnosis (younger age, less education, lower income, obesity, and lymphedema). Treatment with endocrine therapy was a protective factor at 10 months post-diagnosis.
CONCLUSION: Most AABCS report clinically significant sleep disturbance from before diagnosis through 24 months post-diagnosis. These rates appear indicate AABCS experience significant sleep-related disparities.