Abstract P1-10-04: Racial and ethnic differences in weight gain during and after chemotherapy among women with early-stage breast cancer
Authors: Wu R , Crew KD 
Published: May 2019

Abstract
Objective
Clinically significant weight gain of ≥5% from baseline has been commonly reported during chemotherapy treatment for early stage breast cancer and persisting after completion. Based on the known poorer outcomes associated with weight gain after a breast cancer diagnosis, we evaluated differential weight gain by race/ethnicity as a potential explanation for disparities in breast cancer clinical outcomes among racial/ethnic minorities compared to non-Hispanic white women.
Methods
We conducted a retrospective cohort study among women diagnosed with stage I-III breast cancer between 2007 and 2016, who received chemotherapy at Columbia University Medical Center (CUMC) in New York, NY. We extracted data on demographics, clinical characteristics, chemotherapy regimens, and height/weight from the electronic health records. Our main exposure variable of interest was race/ethnicity. The outcome variable was dichotomized as ≥5% weight gain or stable weight (defined as &lt;5% weight gain or loss/≥5% weight loss) from baseline at 3, 6, 12, and 18 months after initiating chemotherapy. We used multinomial logistic regression analyses to determine the association between race/ethnicity and weight gain before and after adjusting for confounders.
Results
Among 789 evaluable women, median age was 55 years (range, 19-92) and the study cohort was racially/ethnically diverse: 39.8% non-Hispanic white, 30.4% Hispanic, 18.0% non-Hispanic black, 10.4% Asian, and 1.4% other. Mean baseline body mass index (BMI) was highest among black women (30.7 kg/m2 ± 7.0), followed by Hispanic (29.4 kg/m2 ± 5.2), non-Hispanic white (27.9 kg/m2 ± 6.9), and Asian (25.5 kg/m2 ± 5.4) women. The proportion of women with ≥5% weight gain increased over time with 13.6% at 3 months, 15.2% at 6 months, 19.0% at 12 months, and 23.6% at 18 months. Compared to non-Hispanic whites, Asian women had a 63% lower odds of ≥5% weight gain (95% Confidence Interval [CI]: 0.15-0.92) at 3 months after initiating chemotherapy. No statistically significant associations were found between other racial/ethnic groups and ≥5% weight gain. Factors associated with weight gain after chemotherapy included younger age at diagnosis, lower baseline BMI, longer duration of chemotherapy, and having Medicaid insurance coverage.
Conclusions
Race/ethnicity was not significantly associated with weight gain after chemotherapy among women with early stage breast cancer. Socioeconomic status (SES) rather than race/ethnicity may be a contributing factor in disparities in weight gain and breast cancer clinical outcomes. Future weight loss programs should target younger, pre-menopausal women and those with lower SES.
Citation Format: Wu R, Crew KD. Racial and ethnic differences in weight gain during and after chemotherapy among women with early-stage breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-10-04.