Background: While consuming a Mediterranean-style diet (MSD) among pregnant women is expected to affect offspring neurodevelopment, the current evidence is limited. This prospective birth cohort study aimed to explore the association of maternal MSD with neurodevelopmental disabilities (NDD) in offspring, especially among children born to mothers with overweight or obesity (OWO) and/or diabetes mellitus (DM) since they have a higher risk for oxidative stress and immune/metabolic disturbances.
Methods: We analyzed data from a subgroup of mother-child dyads enrolled in the Boston Birth Cohort. Maternal dietary information (via food frequency questionnaires, Food frequency questionnaires [FFQ]) and sociodemographic information were obtained via in-person interviews within 24 to 72 hours postpartum. Maternal clinical information and child diagnosis of NDD including autism, attention-deficit/hyperactivity disorder (ADHD), and other developmental disabilities (DD) were extracted from medical records. A Mediterranean-style diet score (MSDS) was calculated using the FFQ. The association of maternal MSDS with NDD, autism, ADHD, and other DD was evaluated using multivariable logistic regression models adjusted for pertinent covariates.
Results: This study included 3153 mother-child pairs, from which we identified diagnoses of 1362 (43.2%) NDD, including 123 (3.9%) case of autism, 445 (14.1%) ADHD, and 794 (25.2%) other DD. In the overall sample, women with a higher maternal MSDS (per standard deviation increase) were less likely to have offspring with NDD (adjusted odds ratio [OR]: 0.904, 95% confidence interval [CI]: 0.817-1.000; P value: 0.049). Using MSDS quintile 1 as the reference, being in the combined group of quintiles 3-5 was associated with a 26% lower likelihood of NDD (adjusted OR: 0.738, 95% CI: 0.572-0.951; P value: 0.019). When stratified by mothers with OWO/DM vs. without OWO/DM, the association between maternal MSDS and offspring NDD was greater in children born to mothers with OWO/DM.
Conclusions: In this prospective birth cohort, a higher maternal MSDS was associated with a lower likelihood of NDD in the offspring. Furthermore, this association of maternal MSDS with offspring NDD was greater in children born to women with OWO/DM. More studies are needed to replicate the findings and further analyze NDD subgroups and explore underlying molecular pathways.
Background: Smoking during pregnancy has been associated with reduced risk of a spectrum of hypertensive (HTN) disorders, known as the "smoking-hypertension paradox."
Objective: We sought to test potential epidemiologic explanations for the smoking-hypertension paradox.
Methods: We analyzed 8,510 pregnant people in the Boston Birth Cohort, including 4,027 non-Hispanic Black and 2,428 Hispanic pregnancies. Study participants self-reported tobacco, alcohol, cannabis, opioids, or cocaine use during pregnancy. We used logistic regression to assess effect modification by race/ethnicity, and confounding of concurrent substances on hypertensive disorders or prior pregnancy. We also investigated early gestational age as a collider or competing risk for pre-eclampsia, using cause-specific Cox models and Fine-Gray models, respectively.
Results: We replicated the paradox showing smoking to be protective against hypertensive disorders among Black participants who used other substances as well (aOR: 0.61, 95% CI: 0.41, 0.93), but observed null effects for Hispanic participants (aOR: 1.14, 95% CI: 0.55, 2.36). In our cause-specific Cox regression, the effects of tobacco use were reduced to null effects with pre-eclampsia (aOR: 0.81, 95% CI: 0.63, 1.04) after stratifying for preterm birth. For the Fine-Gray competing risk analysis, the paradoxical associations remained. The smoking paradox was either not observed or reversed after accounting for race/ethnicity, other substance use, and collider-stratification due to preterm birth.
Conclusions: These findings offer new insights into this paradox and underscore the importance of considering multiple sources of bias in assessing the smoking-hypertension association in pregnancy.