Table 2 Proportions or means and logistic regression analysis of association between attention-deficit hyperactivity disorder (ADHD) and smoking variables (adjusted for age and gender or stratified when age or gender interaction present)
VariableControlsADHD populationOdds ratio (95% CI)
Mean age smoked first whole cigarette, years16.17 (16.05–16.29)14.89 (14.29–15.49)
Mean age started smoking daily (if a current or past daily smoker), years17.97 (17.82–18.11)16.85 (16.19–17.52)
Current smoker (daily or occasional), %20.59 (19.69–21.48)35.42 (29.84–41.00)1.79 (1.37–2.32)
Have ever smoked, %59.75 (58.68–60.81)64.63 (58.42–70.84)1.51 (1.14–2.00)
Mean cigarettes per day (current daily smokers)14.81 (14.39–15.23)15.42 (13.83–17.01)
Mean cigarettes per day (current occasional smokers)3.18 (2.90–3.46)5.33 (3.42–7.25)