The frequency, magnitude and timing of post-diagnosis body weight gain in Dutch breast cancer survivors

To evaluate the association between systemic treatments and post-diagnosis weight gain in breast cancer patients during longer follow-up periods, we conducted a retrospective cohort study (n = 271). Information on adjuvant systemic treatments and repeated body weight measurements was obtained from medical records, and analysed using multi-level regressions.During the first year, a mean weight change of +2.0 kg (SD 4.9) was observed. Overall, 29% of all breast cancer patients had gained 5 kg or more in body weight during total follow-up (median: 3 years). In multi-level analyses, women who received combined systemic treatment gained significantly more weight as compared with women who received no systemic treatment (4.5 kg versus 2.0 kg at 5 years post-diagnosis, p < 0.05).Significant weight gain occurs in breast cancer patients in the Netherlands during the first year post-diagnosis. After the first year, further weight gain mainly occurs in women who receive chemotherapy in combination with endocrine therapy.