Childhood ADHD Linked to Secondhand Smoke. Children exposed to tobacco smoke at home are up to three times more likely to have attention deficit hyperactive disorder (ADHD) as unexposed kids, according to a new study from Spain

I see a reference (that I have NOT fully read) demonstrating a correlation between smoking behavior and ADHD, notwithstanding the original post for the article correlating secondhand smoke with ADHD. Anyone with any statistical background, or otherwise common knowledge, knows that correlation does not prove causation, which is a separate analysis.

However, when skimming the article by McClernon and Kollins, the emphasis clearly seems to be that the causation of high rates of smoking in individuals with ADHD is not yet well known but believed to involve several factors none of which reported to relate to ADHD symptom control of modification, in fact quite the opposite. The authors suggest that the reason people with ADHD smoke so much, has common disease mechanisms with the reasons they have ADHD, basically relating to thought patterns, planning, self control, lack of delayed gratification control, and they relate these in part to genetics.

From the authors' concluding statements:

  • "Variants in genes that regulate monoaminergic transmission are associated with both ADHD and smoking."
  • "ADHD is hypothesized to be the result of an aberrant striatal dopaminergic system which, in turn, gives rise to deficits in executive functioning. Disruption of this system increases the reward value of self-administered nicotine, results in negative reinforcement of attentional and inhibitory control deficits by smoking, worsens nicotine withdrawal, and promotes relapse by increasing baseline levels of impulsivity and reward sensitivity. Drugs that are used to treat both ADHD and smoking cessation exert direct and indirect influence on dopaminergic pathways."
  • "Smoking cessation interventions among individuals with ADHD might attempt to treat ADHD symptoms prior to quitting smoking. Pharmacological interventions will probably focus on medications efficacious in treating ADHD, smoking, or both."

These authors surely paint a different picture than nicotine being beneficial to ADHD so much as they suggesting that smoking cessation will improve ADHD symptoms.

/r/science Thread Parent Link - scientificamerican.com