Abstract B25: Understanding Racial Differences in Health-Related Quality of Life in a Diverse, Population-Based Cohort of Breast Cancer Survivors in North Carolina
Authors: Pinheiro Laura C. , Samuel Cleo A. , Reeder-Hayes Katherine E. , Wheeler Stephanie B. , Olshan Andrew F. , Reeve Bryce B. 
Published: March 2017

Objective: There are over 3 million women in the United States living with breast cancer or who have a history of breast cancer. As the number of women undergoing treatments and surviving breast cancer grows, characterizing changes in health-related quality of life (HRQOL) is critical to ensuring patient-centered breast cancer care. Breast cancer risk and burden varies systemically between Black and White women. Black women are more likely to be diagnosed at younger ages and with more aggressive breast cancer tumors. Although racial disparities in HRQOL are well documented, less is known about differences in HRQOL at distinct phases of breast cancer care. Our objective was to assess racial disparities in HRQOL between active treatment and survivorship phases of the breast cancer care continuum.

Methods: The study used data from the third phase of the Carolina Breast Cancer Study (CBCS-III). CBCS-III enrolled 3,000 women in North Carolina aged 20-74 years diagnosed with invasive, pathologically confirmed breast cancer between 2008 and 2013. HRQOL assessments occurred 5- and 25-months after diagnosis, respectively, representing distinct phases of care. The Functional Assessment of Cancer Therapy for Breast Cancer and the Functional Assessment of Chronic Illness Therapy for Spiritual Well-Being measured HRQOL. We implemented three approaches (Institute of Medicine, Residual Direct Effect and interactive effects of race and socioeconomic factors) to assessing racial disparities to better understand if racial disparities in HRQOL changes existed and to identify potential mediators of disparities in HRQOL. Analysis of covariance models assessed racial differences in changes in HRQOL between active treatment and survivorship. Adjusted models included demographic, socioeconomic, tumor and treatment characteristics.

Results: The cohort included 2,142 Non-Hispanic White (52%) and Black (48%) women with breast cancer who completed both HRQOL assessments. During active treatment, White women reported significantly better physical and functional HRQOL than Black women, but spiritual HRQOL was 2 points higher for Black women. At 25-months post-diagnosis, White women reported HRQOL scores well above U.S norms across physical, social, emotional and functional well-being domains. Black women, however, continued to report physical well-being scores 1.2 points below the U.S norm and 2.3 points below their White breast cancer counterparts. Once demographic, socioeconomic, tumor and treatment characteristics were adjusted for, racial differences narrowed and were not considered clinically meaningful.

Conclusions: Racial differences in physical and functional HRQOL may be mediated by socioeconomic factors. Psychosocial and spiritual HRQOL seem well supported, mitigating negative effects of breast cancer care, especially among Black women. These results inform opportunities for improving the quality and equity of supportive services for women with breast cancer.

Citation Format: Laura C. Pinheiro, Cleo A. Samuel, Katherine E. Reeder-Hayes, Stephanie B. Wheeler, Andrew F. Olshan, Bryce B. Reeve. Understanding Racial Differences in Health-Related Quality of Life in a Diverse, Population-Based Cohort of Breast Cancer Survivors in North Carolina. [abstract]. In: Proceedings of the Ninth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2016 Sep 25-28; Fort Lauderdale, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2017;26(2 Suppl):Abstract nr B25.