Maternal nicotine dependence and prenatal smoking and their association with mental disorders among offspring from the community

Abstract

diagnosed with autistic spectrum disorders (ICD-9CM=299.0X) were initially identified (boys: 3470; girls: 714), followed by the selection of 1:4 control children via matching criteria of offspring's birth year/month, gender, maternal age at delivery, and residential region (boys: 13,878; girls: 2856). History of maternal infection through three trimesters of pregnancy was obtained through outpatient care utilization records, and type of infection was further classified by organ/disease (e.g., respiratory, urinary, and genital tracts) and microorganism (i.e., virus and bacteria). Conditional logistic models were employed to evaluate the risk estimates, with simultaneous adjustment for maternal characteristics (e.g., history of mental disorders, autoimmune diseases, and complication at/after delivery), children's factors (e.g., mental retardation), and antibiotics use due to infection. Results: Pooled analyses demonstrated that genital infection (adjusted odds ratio [aOR]: 1.22; 95% Confidence Interval [95% CI]: 1.03–1.45) and bacterial infection (aOR: 1.19; 95% CI: 1.03–1.37) in the third trimester were associated with increased risk of autism. Further comparison on autistic children by gender suggested that girls were more likely to have mental retardation (15.41% vs. 11.01%, Pb.001), neonatal infections (5.88% vs. 3.54%, Pb .01), and complications at/after delivery (6.02% vs. 4.29%, Pb .5) than boys. Influenza infection during the third trimester (aOR: 3.25; 95% CI: 1.33–7.95) may increase the risk of autism for girls, whereas for boys, perinatal genital infection seems more salient (aOR: 1.21; 95% CI: 1.01–1.47). Conclusions: Our study suggested that perinatal infection, especially in the third trimester, may be associated with increased occurrence of autistic spectrum disorders and such association may also vary by infectious agents and system organs involved. Future research on the role of infection, the mechanism underlying the development of autism, and possible sex variation in such pathways should be addressed.