Race and Patient-reported Symptoms in Adherence to Adjuvant Endocrine Therapy: A Report from the Women's Hormonal Initiation and Persistence Study

Adjuvant endocrine therapy (AET) improves outcomes in women with hormone receptor-positive (HR⁺) breast cancer. Suboptimal AET adherence is common, but data are lacking about symptoms and adherence in racial/ethnic minorities. We evaluated adherence by race and the relationship between symptoms and adherence.

The Women's Hormonal Initiation and Persistence study included women diagnosed with nonrecurrent HR⁺ breast cancer who initiated AET. AET adherence was captured using validated items. Data regarding patient (e.g., race), medication-related (e.g., symptoms), cancer care delivery (e.g., communication), and clinicopathologic factors (e.g., chemotherapy) were collected via surveys and medical charts. Multivariable logistic regression models were employed to calculate odds ratios and 95% confidence intervals (CIs) associated with adherence.

Of the 570 participants, 92% were privately insured and nearly one of three were Black. Thirty-six percent reported nonadherent behaviors. In multivariable analysis, women less likely to report adherent behaviors were Black (vs. White; OR, 0.43; 95% CI, 0.27-0.67; P < 0.001) and with greater symptom burden (OR, 0.98; 95% CI, 0.96-1.00; P < 0.05). Participants more likely to be adherent were overweight (vs. normal weight) (OR, 1.58; 95% CI, 1.04-2.43; P < 0.05), sat ≤ 6 hours a day (vs. ≥6 hours; OR, 1.83; 95% CI, 1.25-2.70; P < 0.01), and were taking aromatase inhibitors (vs. tamoxifen; OR, 1.91; 95% CI, 1.28-2.87; P < 0.01).

Racial differences in AET adherence were observed. Longitudinal assessments of symptom burden are needed to better understand this dynamic process and factors that may explain differences in survivor subgroups.

Future interventions should prioritize Black survivors and women with greater symptom burden.