Maternal smoking during pregnancy and ADHD: a comprehensive clinical and neurocognitive characterization

Nicotine Tob Res. 2013 Jan;15(1):149-57. doi: 10.1093/ntr/nts102. Epub 2012 Apr 22.


Introduction: Evidence from epidemiological studies has consistently shown an association between maternal smoking during pregnancy (MSDP) and attention-deficit/hyperactivity disorder (ADHD). The objective of this study is to test the hypothesis that children with ADHD exposed to MSDP show a distinctive clinical and neurocognitive profile when compared with unexposed children.

Methods: Four hundred and thirty-six children diagnosed with ADHD were stratified by exposure to MSDP and compared with regard to severity of illness, comorbidity, IQ, and executive function as assessed by a battery of neuropsychological tests. All comparisons were adjusted for socioeconomic status, ethnicity, mother's age at child's birth, and maternal alcohol consumption during pregnancy.

Results: Exposed children had more severe behavioral problems with greater externalizing symptoms and more conduct and oppositional defiant disorder items, lower verbal IQ, and a sluggish cognitive profile on the Continuous Performance Test (CPT). Linear regression analyses revealed a dose-response relationship between the average number of cigarettes smoked per day during pregnancy and verbal IQ, CPT omission errors T score and several other clinical variables.

Conclusions: These results suggest that MSDP is associated with a more severe form of ADHD, characterized by more severe clinical manifestations and poorer neuropsychological performance. This phenotypic signature associated with MSDP may help to identify a more homogenous subgroup of children with ADHD.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Alcohol Drinking
  • Attention Deficit Disorder with Hyperactivity / epidemiology
  • Attention Deficit Disorder with Hyperactivity / psychology*
  • Child
  • Female
  • Humans
  • Intelligence Tests
  • Linear Models
  • Male
  • Maternal Age
  • Neuropsychological Tests
  • Pregnancy
  • Prenatal Exposure Delayed Effects*
  • Smoking / adverse effects*
  • Social Class