Caesarean delivery, childhood asthma, and effect modification by sex: An observational study and meta-analysis

Audrey Flak Pennington, Matthew J. Strickland, Mitchel Klein, Carolyn Drews-Botsch, Craig Anthony Hansen, Lyndsey A. Darrow

Research output: Contribution to journalArticle

Abstract

Background: Numerous studies indicate caesarean delivery is associated with childhood asthma. Sex-specific associations were reported in four of these studies, and in all four studies, the estimated association between caesarean delivery and asthma was of greater magnitude among girls, although most report a lack of evidence of multiplicative interaction. Methods: We assessed potential effect modification by sex, on the additive and multiplicative scales, of the association between caesarean delivery and asthma by ages 2 through 6 in up to 17 075 racially diverse children from a retrospective birth cohort, the Kaiser Air Pollution and Pediatric Asthma (KAPPA) Study. We also conducted a random-effects meta-analysis, combining our sex-stratified results (using the odds ratio for compatibility with previous studies) with previously published results. Results: Adjusted risk differences for caesarean delivery and asthma in the KAPPA cohort were higher among girls than boys at every follow-up age. By age 5, caesarean delivery was associated with an absolute 3.8% (95% confidence interval [CI] 0.4%, 7.3%) higher asthma risk among girls and a 1.9% (95% CI −1.7, 5.4) higher risk among boys. The summary odds ratio from the meta-analysis for caesarean delivery and asthma among girls was 1.26 (95% CI 1.14, 1.39) and 1.08 (95% CI 0.98, 1.20) among boys (P = 0.036). Conclusions: Higher, but imprecise, estimates for females across five studies should motivate investigators to estimate sex-specific associations for caesarean delivery and asthma and to explore biological mechanisms or sex-dependent biases that could explain this possible heterogeneity.

LanguageEnglish
Pages495-503
Number of pages9
JournalPaediatric and Perinatal Epidemiology
Volume32
Issue number6
DOIs
Publication statusPublished - 1 Nov 2018

Keywords

  • asthma
  • caesarean delivery
  • effect modification
  • sex

ASJC Scopus subject areas

  • Epidemiology
  • Pediatrics, Perinatology, and Child Health

Cite this

Pennington, A. F., Strickland, M. J., Klein, M., Drews-Botsch, C., Hansen, C. A., & Darrow, L. A. (2018). Caesarean delivery, childhood asthma, and effect modification by sex: An observational study and meta-analysis. Paediatric and Perinatal Epidemiology, 32(6), 495-503. https://doi.org/10.1111/ppe.12510
Pennington, Audrey Flak ; Strickland, Matthew J. ; Klein, Mitchel ; Drews-Botsch, Carolyn ; Hansen, Craig Anthony ; Darrow, Lyndsey A. / Caesarean delivery, childhood asthma, and effect modification by sex : An observational study and meta-analysis. In: Paediatric and Perinatal Epidemiology. 2018 ; Vol. 32, No. 6. pp. 495-503.
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Pennington, AF, Strickland, MJ, Klein, M, Drews-Botsch, C, Hansen, CA & Darrow, LA 2018, 'Caesarean delivery, childhood asthma, and effect modification by sex: An observational study and meta-analysis', Paediatric and Perinatal Epidemiology, vol. 32, no. 6, pp. 495-503. https://doi.org/10.1111/ppe.12510

Caesarean delivery, childhood asthma, and effect modification by sex : An observational study and meta-analysis. / Pennington, Audrey Flak; Strickland, Matthew J.; Klein, Mitchel; Drews-Botsch, Carolyn; Hansen, Craig Anthony; Darrow, Lyndsey A.

In: Paediatric and Perinatal Epidemiology, Vol. 32, No. 6, 01.11.2018, p. 495-503.

Research output: Contribution to journalArticle

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T1 - Caesarean delivery, childhood asthma, and effect modification by sex

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AU - Pennington, Audrey Flak

AU - Strickland, Matthew J.

AU - Klein, Mitchel

AU - Drews-Botsch, Carolyn

AU - Hansen, Craig Anthony

AU - Darrow, Lyndsey A.

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