Predictors of weight gain in a cohort of premenopausal early breast cancer patients receiving chemotherapy.

ABSTRACT

AIM: In breast cancer patients, post chemotherapy weight gain is linked with increased risk of cancer recurrence. We prospectively studied a cohort of premenopausal women receiving contemporary chemotherapy following a diagnosis of breast cancer to examine factors predicting weight increase. METHODS: Between May 2005 and January 2008, 523 patients from the Prospective Outcomes in Sporadic versus Hereditary (POSH) breast cancer study entered this sub-study comparing weight prior to chemotherapy and weight and waist/hip measurements 12-months following chemotherapy. RESULTS: Data from 380 patients were available. Mean (standard deviation [SD]) pre-treatment body mass index (BMI) was 26.3 (5.6) kg/m2; 30% women gained > 5% body weight during the study period. Lower BMI at diagnosis predicted greater subsequent post treatment weight gain (4.3% relative weight gain for those in the 1st quartile of BMI compared to 0.8% for those in the 4th quartile; r = -0.22; p < 0.001). No link to chemotherapy regimens, cigarette smoking, previous parity or chemotherapy induced amenorrhoea was noted. A total of 44% of women had central obesity (post-treatment waist measurement of ≥88 cm). CONCLUSIONS: Almost a third of premenopausal patients receiving adjuvant chemotherapy for breast cancer will gain clinically significant weight and over 40% will have central obesity 12-months following diagnosis. A greater weight gain is predicted by lower pretreatment BMI.