Multilevel Risk Factors for Weight Change after Breast Cancer Diagnosis Among Black Women

Abstract

Background: Weight gain after breast cancer diagnosis increases the risk of mortality. African American/Black breast cancer survivors are more likely to have excess body weight than their White counterparts, which may contribute to their higher mortality rate. Emerging evidence suggests that post-diagnosis weight gain may result from multilevel determinants. However, no study has investigated the multilevel characteristics among Black breast cancer survivors. Objective: To evaluate associations between individual-level factors and neighborhood social and built environment factors with weight change after breast cancer diagnosis among Black women. Methods: We evaluated associations of interest among 785 women enrolled in the Women's Circle of Health Follow-Up Study (WCHFS), a longitudinal study of Black breast cancer survivors in New Jersey. Weight change was primarily based on measurements at baseline and follow-up visits (Median: 10.3 and 23.2 mo. since diagnosis, respectively). Participants were grouped into categories of stable weight (52.4%), ≥3% weight loss (20.0%), and ≥3% weight gain (27.6%). Using multivariate- adjusted multinomial logistic regression and multilevel multinomial logistic regression, we evaluated relative risk ratios (RRRs) for associations between multilevel factors and post-diagnosis weight change category. Results: Black breast cancer survivors who were older at diagnosis, had higher household income, post-menopausal status, and higher baseline BMI were less likely to gain weight compared to women with stable weight. Former smoking, higher tumor stage, and chemotherapy were associated with increased relative risk of weight gain (e.g. RRR-chemo: 1.45, 95% CI: 1.01, 2.08). Black women residing in neighborhoods in the highest tertile for density of walkable destinations had a decreased relative risk of post- diagnosis weight gain (e.g. RRR-T3 highest density vs. T1 lowest: 0.39, 95% CI: 0.20, 0.75), while those residing in neighborhoods with higher density of fast food restaurants had increased relative risk of weight gain (RRR-T3 highest density vs. T1 lowest: 1.94, 95% CI: 1.23, 3.05). Conclusion: Both individual and neighborhood factors may influence the risk of weight gain among Black women after breast cancer diagnosis.