Over one-third of breast cancer survivors experience upper extremity disability. Black women present with factors associated with greater upper extremity disability, including: increased body mass index (BMI), more advanced disease stage at diagnosis, and varying treatment type compared with Whites. No prior research has evaluated the relationship between race and upper extremity disability using validated tools and controlling for these factors. Data were drawn from a survey study among 610 women with stage I-III hormone receptor positive breast cancer. The disabilities of the arm, shoulder and hand (QuickDASH) is an 11-item self-administered questionnaire that has been validated for breast cancer survivors to assess global upper extremity function over the past 7 days. Linear regression and mediation analysis estimated the relationships between race, BMI and QuickDASH score, adjusting for demographics and treatment types. Black women (n = 98) had 7.3 points higher average QuickDASH scores than White (n = 512) women (p < 0.001). After adjusting for BMI, age, education, cancer treatment, months since diagnosis, and aromatase inhibitor status, Black women had an average 4-point (95 % confidence interval 0.18-8.01) higher QuickDASH score (p = 0.04) than White women. Mediation analysis suggested that BMI attenuated the association between race and disability by 40 %. Even several years post-treatment, Black breast cancer survivors had greater upper extremity disability, which was partially mediated by higher BMIs. Close monitoring of high BMI Black women may be an important step in reducing disparities in cancer survivorship. More research is needed on the relationship between race, BMI, and upper extremity disability.
Keywords: Black/African-American; Breast cancer; Disability; Philadelphia, Pa; Upper extremity function.