Does Pet-Keeping Modify the Association of Delivery Mode with Offspring Body Size?
Caesarean-section (CS) delivery increases risk of childhood obesity, and is associated with a distinct early-life gut microbiome, which may contribute to obesity. Household pets may alter human gut microbiome composition. We examined if pet-keeping modified the association of CS with obesity at age 2 years in 639 Wayne County Health, Environment, Allergy and Asthma Longitudinal Study birth cohort participants. Pet-keeping was defined as having a dog or cat (indoors ≥1 h/day) at child age 2 years. We used logistic regression to test for an interaction between CS and pet-keeping with obesity (BMI ≥ 95th percentile) at age 2 years, adjusted for maternal obesity. A total of 328 (51.3 %) children were male; 367 (57.4 %) were African American; 228 (35.7 %) were born by CS; and 55 (8.6 %) were obese. After adjusting for maternal obesity, CS-born children had a non-significant (P = 0.25) but elevated 1.4 (95 % CI 0.8, 2.5) higher odds of obesity compared to those born vaginally. There was evidence of effect modification between current pet-keeping and delivery mode with obesity at age 2 years (interaction P = 0.054). Compared to children born vaginally without a pet currently in the home, children born via CS without a pet currently in the home had a statistically significant (P = 0.043) higher odds (odds ratio 2.00; 95 % CI 1.02, 3.93) of being obese at age 2 years. Pets modified the CS–BMI relationship; whether the underlying mechanism is through effects on environmental or gut microbiome requires specific investigation.
KeywordsBirth cohort Childhood obesity Delivery mode Companion animals
This study was supported by the National Institutes of Health (R01 AI050681, R01 HL113010 and P01 AI089473) and the Fund for Henry Ford Hospital.
- 16.Dominguez-Bello, M. G., Costello, E. K., Contreras, M., et al. (2010). Delivery mode shapes the acquisition and structure of the initial microbiota across multiple body habitats in newborns. Proceedings of the National Academy of Sciences of the United States of America, 107(26), 11971–11975. doi: 10.1073/pnas.1002601107.CrossRefPubMedCentralPubMedGoogle Scholar
- 27.Azad, M. B., Konya, T., Maughan, H., et al. (2013). Infant gut microbiota and the hygiene hypothesis of allergic disease: Impact of household pets and siblings on microbiota composition and diversity. Allergy, Asthma, and Clinical Immunology, 9(1), 15. doi: 10.1186/1710-1492-9-15.CrossRefPubMedCentralPubMedGoogle Scholar
- 28.Fujimura, K. E., Demoor, T., Rauch, M., et al. (2014). House dust exposure mediates gut microbiome Lactobacillus enrichment and airway immune defense against allergens and virus infection. Proceedings of the National Academy of Sciences of the United States of America, 111(2), 805–810. doi: 10.1073/pnas.1310750111.CrossRefPubMedCentralPubMedGoogle Scholar
- 33.Kuczmarski, R. J., Ogden, C. L., Guo, S. S., et al. (2002). 2000 CDC growth charts for the United States: Methods and development. Vital Health Statistics, 11(246), 1–190.Google Scholar
- 37.Lovasi, G. S., Underhill, L. J., Jack, D., et al. (2012). At odds: Concerns raised by using odds ratios for continuous or common dichotomous outcomes in research on physical activity and obesity. The Open Epidemiology Journal, 5, 13–17. doi: 10.2174/1874297101205010013.CrossRefPubMedCentralPubMedGoogle Scholar
- 39.Selvin, S. (1996). Statistical analysis of epidemiologic data (2nd ed.). New York: Oxford University Press.Google Scholar
- 48.Timperio, A., Salmon, J., Chu, B., et al. (2008). Is dog ownership or dog walking associated with weight status in children and their parents? Health Promotion Journal of Australia: Official Journal of Australian Association of Health Promotion Professionals, 19(1), 60–63.Google Scholar
- 53.Collado, M. C., Isolauri, E., Laitinen, K., et al. (2010). Effect of mother’s weight on infant’s microbiota acquisition, composition, and activity during early infancy: A prospective follow-up study initiated in early pregnancy. American Journal of Clinical Nutrition, 92(5), 1023–1030. doi: 10.3945/ajcn.2010.29877.CrossRefPubMedGoogle Scholar