Multilevel Factors for Adiposity Change in a Population-Based Prospective Study of Black Breast Cancer Survivors

Abstract

Purpose: Unfavorable weight change after breast cancer diagnosis increases the risk of mortality, but individual and neighborhood risk factors affecting postdiagnosis weight and body fat changes are unclear among Black women, who have higher rates of obesity and mortality than any other racial/ethnic group.

Methods: Adiposity changes during the period approximately 10 months-24 months after diagnosis were evaluated among 785 women diagnosed between 2012 and 2018 and enrolled in the Women's Circle of Health Follow-Up Study, a population-based prospective cohort of Black breast cancer survivors in New Jersey. Multilevel factors for weight and fat mass change (with gain or loss defined as a relative difference of 3% or more, and considering whether changes were intentional or unintentional) were estimated using multivariable polytomous logistic regressions and multilevel models.

Results: Adiposity gain was prevalent: 28% and 47% gained weight and body fat, respectively, despite a high baseline prevalence of overweight or obesity (86%). Risk factors for fat mass gain included receiving chemotherapy (relative risk ratio: 1.59, 95% CI, 1.08 to 2.33) and residing in neighborhoods with a greater density of fast-food restaurants (relative risk ratio comparing highest with lowest tertile: 2.18, 95% CI, 1.38 to 3.46); findings were similar for weight gain. Only 9% of women had intentional weight loss, and multilevel risk factors differed vastly from unintentional loss.

Conclusion: Both individual and neighborhood factors were associated with adiposity change among Black breast cancer survivors. Residential environment characteristics may offer clinically meaningful information to identify cancer survivors at higher risk for unfavorable weight change and to address barriers to postdiagnosis weight management.

FIG 1.

Multilevel risk factors for weight gain and fat mass gain among Black breast cancer survivors. See Appendix Tables A3 and A4 for weight change–related results not included in Figure 1. For individual-level and clinical factors, multivariable polytomous logistic regressions were adjusted for age, baseline BMI, household income, smoking status, and chemotherapy. For neighborhood-level factors, multivariable multilevel polytomous logistic regressions additionally adjusted for nSES, %Black residents, fast-food restaurant density, and physical activity facility density. For menopausal status, tumor stage, and walkability under study, the model was not adjusted for age, chemotherapy, and nSES, respectively, because of collinearity concerns. AJCC, American Joint Committee on Cancer; BMI, body mass index; HER2, human epidermal growth factor receptor 2; nSES, neighborhood socioeconomic status; Ref, reference; RRR, relative risk ratio; USD, US dollars.

FIG 2.

Multilevel risk factors for unintentional and intentional weight loss among Black breast cancer survivors. Other factors under study were not associated with unintentional or intentional weight loss (data not shown). For individual-level and clinical factors, multivariable polytomous logistic regressions were adjusted for age, baseline BMI, household income, smoking status, and chemotherapy. For neighborhood-level factors, multivariable multilevel polytomous logistic regressions were additionally adjusted for nSES, %Black residents, fast-food restaurant density, and physical activity facility density. For menopausal status, tumor stage, and walkability under study, the model was not adjusted for age, chemotherapy, and nSES, respectively, because of collinearity concerns. For %Black residents, the first two tertiles were combined because of the small sample size in T1. AJCC, American Joint Committee on Cancer; BMI, body mass index; HER2, human epidermal growth factor receptor 2; BMI, body mass index; nSES, neighborhood socioeconomic status; Ref, reference; RRR, relative risk ratio; USD, US dollars.