Weight change patterns among breast cancer survivors: results from the Shanghai breast cancer survival study.

In a population-based cohort study of 5,014 women with stage 0-III breast cancer, we evaluated weight change patterns from diagnosis to 6, 18, and 36 months post-diagnosis. Patients were recruited to the study approximately 6 months after cancer diagnosis between 2002 and 2006 and followed through 36 months post-diagnosis. The medians of weight change from diagnosis to 6, 18, and 36 months post-diagnosis were 1.0, 2.0, and 1.0 kg, respectively. Approximately, 26% of survivors gained > or =5% of their at-diagnosis body weight during the first 6 months after diagnosis, while 37% and 33% of women gained the same percentage of weight at 18 and 36 months post-diagnosis. More weight gain was observed among women who had a more advanced disease stage, were younger, had lower body mass index at diagnosis, were premenopausal, or received chemotherapy or radiotherapy during the first 6 months after cancer diagnosis. Multivariate analyses indicated that age at diagnosis, body size, comorbidity, and disease stage independently predicted weight gain from diagnosis to 36 months post-diagnosis. In summary, weight gain is common over the first 3 years after breast cancer diagnosis among Chinese women. More research is needed to investigate measures to prevent weight gain in breast cancer survivors.