A comprehensive list of sociodemographic, dietary and lifestyle factors has limited predictive power in determining RBC folate concentrations maximally protective against neural tube defects

Optimal maternal folate status is associated with a reduction in the occurrence of neural tube defects (NTD). Socio‐demographic and lifestyle factors collected as part of the Canadian Health Measures and the National Health and Examination Surveys account for less than 30% of the variation in RBC folate concentration, a measure of tissue stores. Using a comprehensive literature‐derived list of potential predictors of folate status, our aim was to re‐evaluate maternal socio‐demographic, dietary and lifestyle factors associated with a RBC folate maximally protective against NTD (≥906 nmol/L) to determine the feasibility of developing a tool that could be used by health clinicians to predict RBC folate ≥906 nmol/L. A Block food frequency questionnaire, and detailed additional questions on: dietary sources of folate; folic acid and B12 supplement intake; education; ethnicity; income; birth status; age, smoking; and alcohol use were collected from 101 women of reproductive age. Mean RBC folate was 849.9±264.6 nmol/L as determined by microbial assay; 39% had RBC folate concentrations ≥906 nmol/L. Only higher folic acid supplement intake had a positive association (OR=2.6; 95% CI 1.38, 4.9) with RBC folate ≥906 nmol/L while low alcohol intake was negatively associated (OR=0.3; 95% CI 0.09, 1.0). We conclude that use of a comprehensive list of factors did not improve the prediction of RBC folate protective against NTD. Grant Funding Source : CIHR (218776), NSERC (46513), and Hospital for Sick Children RTC Matching Funds Program (BH)