Background: Prevalences of NTDs are typically 50-100% greater among Hispanic women compared to non-Hispanic Whites. This article examines whether markers of acculturation such as "language preference" allow the identification of high-risk groups within the Hispanic population. It also examines whether known NTD risk factors explain observed differences in risk among Hispanic women who are more and less acculturated.
Methods: This population-based case-control study of deliveries in selected California counties from 1999-2003 included 337 NTD cases and 626 nonmalformed, liveborn controls.
Results: Relative to less acculturated US-born Hispanic women (i.e., women who preferred reading and speaking Spanish), other subgroups (i.e., US-born Hispanic women who preferred English, foreign-born Hispanic women regardless of "language preference", and non-Hispanic White women) had approximately twofold increased risks of spina bifida. Only the less acculturated foreign-born women (i.e., women with a preference for Spanish) had substantially increased risk of anencephaly (OR 1.7; 95% CI 0.9, 3.4). Adjustment for several NTD risk factors (maternal intake of folic acid-containing supplements, dietary folate intake, body mass index, food insecurity, stressful life events, smoking, alcohol intake, education, income, and neighborhood education and poverty) resulted in modest or no reductions in most of the ORs.
Conclusions: The explanation for variability in NTD risks among Hispanic and non-Hispanic White women therefore likely extends beyond most known NTD risk factors.