Almost 20% of breast cancer survivors experience excess weight gain, according to a study presented at ENDO 2024, the Endocrine Society's annual meeting in Boston, Mass.
The study aimed to describe weight trends and identify predictors of weight gain in breast cancer (BC) survivors. The research included 4,744 BC survivors from the Mayo Clinic Breast Cancer Registry who were followed for up to 6 years after diagnosis.
"Weight gain after breast cancer diagnosis and treatment is a common concern among survivors and poses a risk factor for breast cancer recurrence," said study author Maria Daniela Hurtado Andrade, MD.
"In addition to increasing the risk of breast cancer recurrence, weight gain increases the risk for cardiovascular disease. In breast cancer survivors, cardiovascular disease is the leading cause of death after breast cancer itself," said Dr. Hurtado Andrade, of the Mayo Clinic in Jacksonville, Fla.
The researchers analyzed data on weight at baseline, and at years 1, 4, and 6 after BC diagnosis. They identified BC survivors with weight gain greater than 10% at each of these time points and conducted univariable logistic regression analyses to identify predictors of weight gain.
Variables considered included demographics, anthropometrics, BC clinical and pathologic characteristics, BRCA1 and BRCA2 genetic mutation status, and treatment modalities. Factors associated with more than a 10% weight gain included: lower weight, younger age, advanced cancer stage, hormone-positive breast cancer, mutations of the BRCA2 gene, aggressive surgery, and chemotherapy or endocrine therapy.
The study found that the average weight change 1 year after BC diagnosis was negligible compared to baseline. However, there were small but significant average increases in weight by years 4 and 6. At year 1, 10% of BC survivors gained more than 10% of their baseline weight, increasing to 15% at year 4, and 18% at year 6.
"The variables we found to be associated with excess weight gain could be used as predictors of weight gain in this population," Dr. Hurtado Andrade said. "Identifying these patients early in the survivorship course will allow us to institute measures to prevent excess weight gain, thereby improving breast cancer and cardiovascular disease outcomes."
No conflicts of interest were disclosed.