Prenatal antimicrobial use and early-childhood body mass index.

BACKGROUND/OBJECTIVES: Growing evidence suggests that antibiotic use is associated with childhood body mass index (BMI), potentially via mechanisms mediated by gut microbiome alterations. Less is known on the potential role of prenatal antimicrobial use in offspring obesity risk. We examined whether prenatal antibiotic or antifungal use was associated with BMI at the age of 2 years in 527 birth cohort participants. METHODS/SUBJECTS: Antimicrobial use was obtained from the prenatal medical record. Height and weight were measured at the age of 2 years. Overweight/obesity was defined as a BMI ⩾85th percentile. RESULTS: A total of 303 (57.5%) women used antibiotics and 101 (19.2%) used antifungals during pregnancy. Prenatal antifungal use was not associated with child BMI at the age of 2 years. In the fully adjusted model, prenatal antibiotic use was associated with a 0.20±0.10 (P=0.046) higher mean BMI Z-score at the age of 2 years. Associations between prenatal antibiotic use and childhood BMI varied by trimester of exposure, with first or second-trimester exposure more strongly associated with larger BMI at the age of 2 years for both BMI Z-score (interaction P=0.032) and overweight/obesity (interaction P=0.098) after covariate adjustment. CONCLUSIONS: Prenatal antibiotic, but not antifungal, use is associated with larger BMI at the age of 2 years; associations were stronger for antibiotic exposures in earlier trimesters. Future studies examining whether these associations are due to alterations in the maternal and/or infant microbiome are necessary. Children who are overweight at the age of 2 years are at higher risk for being overweight as they age; prenatal antibiotic use is a potentially modifiable exposure that could reduce childhood obesity.

Asthma, body mass, gender, and Hispanic national origin among 517 preschool children in New York City.

BACKGROUND: Striking differences in asthma prevalence have been reported among Hispanic adults and children living in different cities of the USA. Prevalence is highest among those of Puerto Rican and lowest among those of Mexican origin. We hypothesized that body size would mediate this association. METHODS: Parents of children in New York City Head Start programs completed a questionnaire including demographic factors, health history, a detailed history of respiratory conditions, lifestyle, and home environment. Children's height and weight were measured in home visits. Logistic regression was used to model the association of asthma with body mass index percentile (<85th percentile, gender/age specific vs>or=85th percentile, gender/age specific), national origin, and other factors. RESULTS: Of 517 children at mean age of 4.0 +/- 0.6 years, 34% met the study criteria for asthma, and 43% were above the 85th percentile. Asthma was strongly associated with non-Mexican national origin, male gender, allergy symptoms, and maternal asthma, and marginally with body size. The odds of asthma among boys of non-Mexican origin was 5.9 times that among boys of Mexican origin [95% confidence interval (CI): 2.9-12.2]; the comparable odds ratio (OR) among girls was 1.8 (95% CI: 0.9-3.6). Body mass was associated with asthma among girls [OR = 2.0 (95% CI: 1.1-3.7)], but not boys [OR = 1.4 (95% CI: 0.8-2.6)]. CONCLUSIONS: The association of asthma with both body mass and national origin was gender-specific among the children in our study. Ours is one of the first studies to report on pediatric asthma in different Hispanic populations in the same city, by gender.

Preliminary studies on the effect of moderate physical activity on blood levels of glutathione.

Molecular epidemiological approaches are being used to study how physical activity may protect against cancer. Prior epidemiological data suggest that physical activity protects against lung cancer; however, interpretation of these data is complicated by potential confounding by smoking. Glutathione (GSH) detoxifies cigarette smoke carcinogens and the paper tests whether physical activity levels are associated with blood GSH levels. Study subjects were enrolled in a chemoprevention trial testing whether antioxidant micronutrient supplementation reduces genetic damage from cigarette smoking. Physical activity data were collected by questionnaire from 178 subjects at 12 months of follow-up in the trial. Total GSH (tGSH), which is the sum of free and protein-bound GSH and glutathione disulfide levels, was measured using the 5,5'-dithiobis-(2-nitrobenzenoic acid) colormetric assay with red blood cell samples collected at the 12-month time point. In multivariate linear regression analyses that controlled for gender and cigarettes smoked per day, tGSH was positively associated with hours per week of moderate intensity activity (beta=0.005, p=0.02). Hours per week of vigorous intensity activity were unassociated with tGSH and the effect of moderate activity remained after control for vigorous activity. The results are consistent with prior research showing differential effects of moderate and vigorous activity and suggest a mechanism through which physical activity may influence lung cancer risk.