Maternal prenatal smoking and long-term gastrointestinal morbidity of the offspring: A population-based cohort analysis

Abstract

Tobacco consumption in the form of cigarette smoking is one of the most prevalent controllable risk factors for adverse health outcomes and is a known reproductive toxin. We aimed to study the effect of maternal cigarette smoking during pregnancy on the risk of long-term gastrointestinal (GI) morbidity of their offspring. A population-based cohort analysis was performed comparing long-term GI-related hospitalizations among offspring of smoking mothers compared with offspring of non-smoking mothers up to the age of 18. The analysis included all singletons born between the years 1999–2014 at a single tertiary medical center. A Kaplan-Meier survival curve was used to compare the cumulative GI morbidity, and a Cox proportional hazards model was constructed to adjust for confounders. The study population included 242,342 children who met the inclusion criteria, 2861(1.2 %) of them were born to smokers. Offspring of smoking mothers were found to have higher rates of GI-related hospitalizations (7.2 % vs. 5.4 %, p < 0.01). Furthermore, the cumulative incidence of long-term GI morbidity was higher compared with those born to non-smoking mothers (log-rank p < 0.01). Specifically, an increased risk for inflammatory bowel disease was noted (OR = 1.48, 95 % CI 1.2–1.8, P < 0.01). Using a Cox proportional hazards model, controlling for confounders including maternal age, ethnicity, maternal diabetes mellitus and hypertensive disorders of pregnancy, birth weight, prematurity and mode of delivery, the association between maternal smoking during pregnancy and long-term GI morbidity of the offspring remained significant (adjusted HR = 1.54, 95 % CI 1.3–1.8, P < 0.01). In-utero exposure to maternal smoking is associated with an increased risk for long-term GI morbidity of the offspring.