Potential role of perceived discrimination and sociodemographics on racial disparities in breast cancer symptom burden.

Abstract

Adjuvant endocrine therapy reduces breast cancer recurrence, but symptom burden contributes to nonadherence, particularly among Black women. We examined how patient sociodemographic factors and perceived discrimination are associated with symptoms and Black-White differences in symptoms during early treatment course of adjuvant endocrine therapy. We conducted a post hoc analysis using survey data collected at study enrollment in the THRIVE trial from November 15, 2018, to June 11, 2021, among women with early-stage breast cancer. Symptom burden was assessed by the Functional Assessment of Cancer Therapy-Endocrine Subscale within 8 weeks of adjuvant endocrine therapy initiation. Covariates included sociodemographic and clinical information and perceived discrimination. Multivariable regressions and Kitagawa-Oaxaca-Blinder decomposition evaluated how these patient characteristics are associated with Black-White differences in symptoms. Among 272 participants, 35.7% self-identified as Black and 64.3% as White. Black women reported more symptoms (lower Functional Assessment of Cancer Therapy-Endocrine Subscale scores) than White women (60.7 vs 64.3, P = .004) and similar discrimination scores (5.44 vs 5.54, P = .17). Experiencing less discrimination (ie, each unit increase in discrimination score, 1.93, 95% confidence interval [CI] = 0.08 to 3.78), older age groups (65-83 vs 30-49 years: 4.84, 95% CI = 1.15 to 8.54), and higher income (≥400% vs <200% federal poverty level = 5.72, 95% CI = 2.12 to 9.33) was associated with lower symptom burden. Decomposition analyses attributed 84.6% of Black-White symptom differences to patient characteristics, with income explaining the largest proportion, while perceived discrimination did not explain symptom burden differences. Black women experienced higher early symptoms during adjuvant endocrine therapy. Although perceived discrimination was associated with greater symptom burden, it did not clinically or statistically significantly explain Black-White differences in symptoms. Income explained the largest portion of Black-White symptom differences. Addressing income inequality is essential for equitable symptom management.