ASPO Abstracts
Dietary intake of nutrients involved in folate-mediated one carbon metabolism and risk for endometrial cancer
Category: Lifestyles behavior, energy balance and chemoprevention, Behavioral science and health communication
Conference Year: 2018
Abstract Body:
Purpose Studies disagree as to whether intake of nutrients involved in folate-mediated one-carbon metabolism influences endometrial cancer risk; most research comes from small case-control studies. Methods We used data from the NIH-AARP Diet and Health Study, a large prospective cohort, and Cox proportional hazards models to evaluate endometrial cancer risk associated with intake of methionine and vitamins B9 (total folate, natural folate, synthetic folate/folic acid), B2, B6, and B12. We also estimated associations by follow-up time (‰¤3 or >3 years) and by BMI (<25 or 25 kg/m2). Results During 16 years of follow-up, we identified 2,329 endometrial cancer cases among 114,414 participants. Compared to those with the lowest intakes of total folate, women consuming the highest amounts were older, had more years of education, and were less likely to be overweight/obese. Greater consumption of total folate, natural folate, B2, B6, and B12 increased risk for endometrial cancer (hazard ratios [HR] ranging from 1.14 to 1.24 for the highest quintile [Q5] versus the lowest [Q1]). Greater intakes of synthetic folate [Q5 vs. Q1: 1.38 (1.00-1.90)] and B6 [Q5 vs. Q1: 1.72 (1.26- 2.35)] increased risk for endometrial cancer when cancer diagnosis was within 3 years of baseline. Elevated risks associated with natural folate were apparent regardless of time to diagnosis. Increased risks were indicated for the highest intakes of B2, B12, and methionine among women who were overweight/obese, while null risks were suggested among normal/underweight women (p- heterogeneity 0.40, 0.11, and 0.04 respectively). Conclusions High intakes of several B-vitamins were associated with modestly increased risk for endometrial cancer, especially among women at risk for a cancer precursor, endometrial hyperplasia (i.e., women ‰¤3 years before cancer diagnosis and those who are obese). Future studies are needed to determine if dietary modification reduces cancer risk among women with hyperplasia.
Keywords: folate, endometrial cancer, B vitamins, obesity