Association between smoking and attention-deficit/hyperactivity disorder symptoms in a population-based sample of young adults

CONTEXT: Attention-deficit/hyperactivity disorder (ADHD) has been associated with increased risk of smoking, and some studies have suggested that inattentive symptoms specifically may underlie this risk. Few studies, however, have examined ADHD symptoms in nonclinical samples to determine the extent to which the number of symptoms-independent of the full diagnosis-confer risk for smoking-related outcomes. OBJECTIVE: To evaluate the relation between smoking-related variables and the number of retrospectively reported ADHD inattentive and hyperactive/impulsive symptoms in a population-based sample of young adults. DESIGN, SETTING, AND PARTICIPANTS: The study population consists of 15 197 eligible participants from wave III of the National Longitudinal Study of Adolescent Health, a nationally representative sample of adolescents followed from 1995 to 2002. MAIN OUTCOME MEASURES: Logistic regression was used to examine the relation between self-reported ADHD symptoms and the lifetime likelihood of being a regular smoker, defined by having smoked at least 1 cigarette a day for 30 days. For individuals reporting regular smoking, we also examined the extent to which ADHD symptoms predicted age at onset of regular smoking and number of cigarettes smoked. RESULTS: A linear relation was identified between the number of self-reported inattentive and hyperactive/impulsive symptoms and smoking outcome measures (P<.001 for each symptom domain). Controlling for demographic and conduct disorder symptoms, each reported inattention and hyperactivity/impulsivity symptom significantly increased the likelihood of ever regular smoking (odds ratio [OR], 1.11; 95% confidence interval [CI], 1.08-1.14 and OR, 1.16; 95% CI, 1.13-1.19, respectively). For those reporting lifetime regular smoking, reported symptoms decreased the estimated age at onset and increased the number of cigarettes smoked. CONCLUSIONS: Self-reported ADHD symptoms were found to be associated with adult smoking outcome variables in this nationally representative sample, providing further evidence of a likely link between ADHD symptoms and risk for tobacco use.