MODIFIABLE RISK FACTORS FOR OROFACIAL CLEFTS AMONG HISPANIC AND NON-HISPANIC INDIVIDUALS IN THE UNITED STATES

Background: Orofacial clefts (OFC) are a common birth defect in the United States (US) and prevalence varies by Hispanic ethnicity. The effect of several modifiable exposures, like maternal dietary patterns, remain largely unexplored, and recognized risk factors have only been established in primarily non-Hispanic White (NHW) cohorts. We utilized data from the National Birth Defects Prevention Study (NBDPS), a population-based case-control study, to better understand the effect of maternal diet on OFC and the impact of other OFC risk factors on Hispanics in the US.Methods: To assess the impact of maternal diet, we used a Latent Class Analysis to identify unknown dietary patterns among the NBDPS population. We used these patterns in crude and adjusted logistic regression to estimate the odds of OFC for each class. To assess the impact of risk factors specific to Hispanics, we performed crude and adjusted logistic models for 15 established risk factors among Hispanic NBDPS participants. We estimated average adjusted population attributable fractions (aaPAFs) for the 6 most established risk factors. aaPAFs were stratified by acculturation to partially account for cultural heterogeneity within this population. aaPAFs were also created for NHW NBDPS participants to provide context for results. Results: A dietary pattern with a relatively higher intake of fruits, vegetables, fish, and dark bread significantly reduced the odds of all OFC phenotypes, when compared to a diet with a relatively higher intake of white bread, chips, and soda, and lower intake of fruits and vegetables. This comparison was true of patterns derived for both the full (Aim 1) and Hispanic (Aim 2) NBDPS population. Among Hispanic individuals, secondhand smoke was associated with a larger increase in OFC than smoking. Diet was associated with the largest aaPAF for most phenotypes, regardless of Hispanic ethnicity. Most aaPAFs varied by acculturation although estimates were imprecise. Conclusions: The persistent effect of maternal diet in both populations and the unique trends observed in our Hispanic risk factor profile warrants further investigation. Additional focus on modifiable risk factors for OFC, and their specific influence on Hispanics, may inform public health prevention priorities and increase efficacy of current prevention strategies.Doctor of Philosoph