Weight change and its correlates among breast cancer survivors.

We assessed weight change from diagnosis to approximately 18 mo after cancer diagnosis and evaluated its correlates in a large, population-based, cohort study of women diagnosed with stage 0-IV breast cancer. A total of 4,561 cases with weight information 1 yr prior to diagnosis, at diagnosis, and at the 18-mo postdiagnosis interview were included in the study. Multinomial logistic regression models were conducted to examine the association of weight change from diagnosis to 18 mo after diagnosis with sociodemographic, clinical, and lifestyle factors. The mean weight change from diagnosis to 18 mo after diagnosis was a gain of 1.7 kg (median: 2.0). Overall, 61% of women gained weight, 27% gained 2-5 kg, and 24% gained ≥5 kg, while approximately 14% lost >2 kg during the 18-mo postdiagnosis period. Greater weight gain was significantly related to younger age, premenopausal status, mixed receptor status, more advanced disease stage, prediagnosis weight loss, higher dietary intake, and cigarette smoking. Women with obesity and serious comorbidity were more likely to lose weight. Moderate exercise was not significantly related to weight change. Weight gain is common among breast cancer survivors. Sociodemographic, clinical, and lifestyle factors are related to weight change. Appropriate intervention strategies should be developed.