Weight change trajectory in women with breast cancer receiving chemotherapy and the effect of different regimens

Aims and objectives To investigate the trajectory of weight change in Taiwanese women with breast cancer after starting chemotherapy and the impact of chemotherapy regimens on weight change while controlling for age, menopausal status, body mass index, lymph node involvement and changes in habits of dietary fat intake and exercise. Background Weight gain after adjuvant chemotherapy in women with breast cancer has negative impact on health outcomes. Design Longitudinal, clinical observational study. Methods Weights were repeatedly measured in 147 women with breast cancer stages I–III. Hierarchical linear modelling was used to analyse these longitudinal data. Results The overall pattern of weight change was a cubic form beginning with a mean of 56·9 kg before chemotherapy. It gradually increased to 59·4 kg at 8·5 months after the first chemotherapy followed by a decrease to 58·5 kg at 21·5 months. During the last 2·5 months, weight increased slightly and never returned to the initial level. After controlling for confounders, steeper weight change was observed among women receiving cyclophosphamide, methotrexate and fluorouracil. The highest weight gain in the cyclophosphamide, methotrexate and fluorouracil group was 2·9 kg (5%) vs. 0·9 kg (1%) in the anthracycline‐based group. Conclusion The trajectory of body weight change within two years after chemotherapy shows a trend of gradual ascent, followed by a small decline and a slight increase in the last 2·5 months. The chemotherapy regimen can predict the trend after controlling for other confounders; women on cyclophosphamide, methotrexate and fluorouracil have a steeper weight change. Relevance to clinical practice Nurses can inform women with breast cancer about the expected changes in body weight after chemotherapy to reduce their uncertainty. Future studies on effective interventions to minimise chemotherapy‐induced weight gain are needed.