1. Assessing the effect of cesarean section on Crohn’s Disease
Pascale Gagnon1
1. Interdisciplinary School of Health Science, University of Ottawa
INTRODUCTION
METHODS
RESULTS
Objective
to evaluate the effect of caesarean delivery on the subsequent development of Crohn's disease in developed countries.
Background
Crohn’s Disease (CD) is an Inflammatory Bowel Disease (IBD) characterize by a dysbiosis of the bowel.
Incidence of CD is increasing in developed countries
Cesarean section (CS) used to be a urgent procedure due to pregnancy complication. CS is also increasing in developed countries.
Rationale
Hygiene Hypothesis
Early colonisation of the bowel
Perinatal risk factors associated with inflammatory and autoimmune diseases: pregnancy and first years of life exposures associated with asthma and type 1 diabetes.
How does CS could increase CD risk: vaginal delivery first expose the new born to vaginal tract bacteria while CS is likely to expose him to atypical bacteria.
Why this review is important: CS and CD are increasing only in developed countries. study findings are conflicting.
Exclusion Criteria
Mothers with IBD
No distinction between CD and others IBD
Analysis
8 studies were included : 4 case-control and 4 cohort (figure 1)
The assessment of methodological quality
was based of the two systematic reviews
published in ,10.
Data extraction was done and potential bias were listed. The quality of the studies depend on the statistical analysis made to reduce those potential bias (table 1).
Different outcomes measurements could lead to misclassification
Not all reviews adjusted values for potential bias
Socioeconomic status (ES) (selection bias, response bias)
elective vs acute CS (difference in the procedure)
Breastfeeding
CONCLUSION & DISCUSSION
The overall studies demonstrate no significant association between CS and CD.
Two studies find a statistically significant association between CS and 1,4
Six studies demonstrated no significant associations2,3,5,6,7,8
Three studies find a significant increasing risk of CD for the boys delivered by CS 1,3,7
Two studies divided CS intervention in elective CS and acute CS. However, they find opposites results 4,8
Potential bias and limitation
SES could induce potential bias
Response bias
Selection bias for case-control studies
Misclassification bias
due to self-report questionnaires
Diagnosis criteria for CD are very similar to ulcerative colitis (UC)
others
Further research:
Evaluate the risk of CD associate with elective CS vs acute CS
Understanding the mechanism leading to the increased risk of CD among boys delivered by CS
Investigate the impact of SES on CD
RESULTS
Odd ratio were calculated with 95% CI for evaluating the risk of CD associated with CS.
Raw data were not always available.
Studies characteristics and statistical analysis are showed in table 2
Two systematic review/meta-analysis (not included in the systematic review) had opposites findings. However, there were limitations and methodological mistakes in both9,10
All studies adjusted values for the most plausible confounders (age, gender, smoking, family history of IBD, preterm of birth)
Three studies were done with pediatric populations: high heterogeneity and different statistical analysis
METHODS
Study Design
Structured review / Literature review
Search Strategy
PUBMED
Key words: Crohn’s disease,
Inflammatory bowel disease,
cesarean section, caesarean,
mode of delivery, perinatal
Peer reviewed
Inclusion Criteria
RCTs, case-control and cohort studies
Complete medical data of perinatal context
Confirmed diagnosis of CD (ICD codes: K50.0-K50.9; histologic and/or radiologic tests)
Developed countries populations (for a better quality assessment and control of confounding)
REFERENCES
Andersen V, Erichsen R, Froslev T, Sorensen H & Ehrenstein V. (2013). Differential risk of ulcerative colitis and Crohn’s disease among boys and girls after cesarean delivery. Inflamm Bowel Dis,
Decker E, Engelmann G, Findeisen A, Gerner P, Laass M, Ney D, et al. (2010). Cesarean delivery is associated with celiac disease but not inflammatory bowel disease in children. Pediatrics, 125, 1433–1440.
Malmborg P, Bahmanyar S, Grahnquist L, Hildebrand H, Montgomery S. (2012). Cesarean section and the risk of pediatric Crohn’s disease. Inflamm Bowel Dis, 18,703–708.
Ponsonby AL, Catto-Smith AG, Pezic A, Dupuis S, Halliday J, Cameron D, et al. (2009). Association between earlylife factors and risk of child-onset Crohn’s disease among Victorian children born : a birth cohort study. Inflamm Bowel Dis, 15, 858–866.
Roberts SE, Wotton CJ, Williams JG, Griffith M, Goldacre MJ. (2011). Perinatal and early life risk factors for inflammatory bowel disease. World J Gastroenterol, 17, 743–749.
Sonntag B, Stolze B, Heinecke A, Luegering A, Heidemann J, Lebiedz P, et al. (2007). Preterm birth but not mode of delivery is associated with an increased risk of developing inflammatory bowel disease later in life. Inflamm Bowel Dis, 13, 1385–1390
Bernstein C-N., Banerjee, A., Targownik, L-E., Singh, H., Ghia, J-E., Burchill, C., Chateau, D. & Roos, L-L. (2016). Cesarean Section Delivery Is Not a Risk Factor for Development of Inflammatory Bowel Disease: A Population-based Analysis. Clinical Gastroenterology and Hepatology, 14(1), 50
Kristensen,K. & Henriksen, L. Cesarean section and disease associated with immune function. The Journal of Allergy and Clinical Immunology, 137(2),
Li,Y., Yun, T. et all. (2014). Cesarean delivery and risk of inflammatory bowel disease: a systematic review and meta-analysis. Scandinavian Journal of Gastroenterology, 49(7),
Bruce A. et all. (2014). Mode of Delivery and Risk of Inflammatory Bowel Disease in the Offspring: Systematic Review and Meta-analysis of Observational Studies. Inflammatory bowel diseases, 20(2),
Higgins. (2008). Cochrane Handbook for Systematic Reviews of Interventions. England: Iley-Blackwell.
ACKNOWLEDGEMENTS
I would like to thanks Dr. Jacques Gagnon for the methodological advise and the moral support provided during this project.