Changes in Weight and Body Composition Among Women With Breast Cancer During and After Adjuvant Treatment: A Prospective Follow-up Study

BACKGROUND: Antineoplastic adjuvant treatment for breast cancer can cause changes in women's weight and body composition and influence their general health and survival.

OBJECTIVE: The aim of this study is to investigate the extent and patterns of change in weight and body composition after current standard adjuvant antineoplastic treatment for breast cancer.

METHODS: Data on weight and body composition from 95 women with breast cancer Stage I to III were obtained during 18 months on a bioelectric impedance analyzer. Changes and odds ratio (OR) were calculated by a linear mixed model and logistic regression.

RESULTS: At 18 months, there was an increase in weight of 0.9 kg (95% confidence interval [CI], 0.3-1.5; P = .003) and an average positive association of 0.35 kg/cm increased waist circumference (95% CI, 0.29-0.42 kg; P < .0001). Relative weight changes ranged from -12.7% to 20.5%. Weight gains related to increased body fat were observed mainly in premenopausal women receiving chemotherapy (1.4 kg; 95% CI, 0.4-2.4; P = .007). For menopausal status, OR was 2.9 (95% CI, 1.14-7.1; P = .025), and for chemotherapy, OR was 2.6 (95% CI, 1.03-6.41; P = .043). The OR for weight loss in Stage III breast cancer was 12.5 (95% CI, 1.21-128.84; P = .034) and 4.3 (CI, 1.07-17.24; P = .40) for comorbidity.

CONCLUSIONS: Results demonstrate that weight changes in a pooled sample are overestimated. However, premenopausal women receiving anthracycline-based chemotherapy show a tendency toward a body composition with increasing fat mass.

IMPLICATIONS FOR PRACTICE: A scheduled assessment of changes in weight and body composition is relevant at 18 months after treatment. To compare future studies, common measuring and cutoff points are needed.