Maternal smoking patterns during pregnancy and childhood and offspring risk of suicidal ideation and attempt

• In Event: Diverse Mechanisms in the Development of Internalized Distress and Self-Harm

Abstract

Background. Prevention of suicidal ideation and attempt in youth is a crucial public health concern. Studies supporting a developmental model of suicide risk6,7 show that such vulnerability may arise during pregnancy and early childhood via exposure to adversities that can impact children’s neurodevelopment. Exposure to maternal smoking during pregnancy is widely recognized as a potential risk factor for adverse childhood neurodevelopmental outcomes. However, few studies investigated the association between maternal smoking during pregnancy and offspring suicide risk, none considering the contribution of smoking exposure after childbirth.
Objective. To investigate associations between maternal smoking patterns during the pre- and post-natal periods and adolescent suicidal ideation and attempt.
Method. We used group-based trajectory modeling to identify longitudinal patterns of maternal smoking from the prenatal period the end of childhood (children’s age 12 years, 10 assessments) among participants in the Québec Longitudinal Study of Child Development (N=1623). We estimated associations between smoking patterns and self-reported adolescent suicidal ideation and attempt (ages 13-20). Background confounding factors (e.g., socioeconomic, familial, mental health) were controlled using propensity score inverse-probability weighting (IPW).
Results. Participants reporting suicidal ideation and attempt were 9.3% and 8.4%, respectively. We identified four maternal smoking patterns (Figure 1): no/low (66.5%), increasing (5.5%), decreasing (9.3%), persistent (18.5%). Background variables were significantly different across the four maternal smoking patterns, but propensity score IPW successfully balanced such differences (Figure 2). In unadjusted logistic regression, we found that children exposed to patterns of persistent (OR=2.92, CI=1.99-4.30) and increasing (OR=2.06, CI=1.13-3.74) maternal smoking were more likely to attempt suicide, compared to non-exposed children. However, accounting for confounding factors using IPW fully explained the association between increasing smoking and suicide attempt (OR=0.95, CI=0.39-2.09) but only reduced the association between persistent exposure and suicide attempt (OR=2.30, CI=1.04-4.99). No increased suicide attempt risk was found for children of mothers with a decreased smoking pattern. We found no associations for suicidal ideation. In complementary analyses, no association was found between maternal smoking heaviness at each specific time point and suicide attempt, suggesting that the observed association between persistent smoking patterns and suicide attempt was not attributable to heavy exposure during a sensitive period (e.g., pregnancy), but rather to the cumulative exposure over time.
Conclusions. Offspring of mothers who smoked persistently and heavily prenatally and postnatally were at increased risk of suicide attempt in adolescence. Future studies should elucidate biological and psychosocial mechanisms potentially at play in these associations.

Authors

• Massimiliano Orri, University of Bordeaux
  Presenting Author

• Nicholas Chadi, University of Montreal
  Non-Presenting Author

• Marilyn N Ahun, Harvard University
  Non-Presenting Author

• Jean Richard Seguin, Université de Montréal
  Non-Presenting Author

• Richard E. Tremblay, University of Montreal
  Non-Presenting Author

• Michel Boivin, Universite Laval
  Non-Presenting Author

• Gustavo Turecki, McGill University
  Non-Presenting Author

• Marie-Claude Geoffroy, McGill University
  Non-Presenting Author

• Sylvana M Côté, Université de Montréal (UdeM)
  Non-Presenting Author