Smoking and ADHD: an evaluation of self medication and behavioral disinhibition models based on comorbidity and personality patterns

Abstract

Objective: The prevalence of smoking is significantly increased among adults with Attention-Deficit/Hyperactivity Disorder (ADHD), and this association has a significant impact in both disorders, ascribed to either self-medication or behavioral disinhibition hypotheses. However, little is known about clinical variables associated with cigarette smoking among patients with ADHD. The present study evaluates comorbidity, demographic and personality profiles of patients with ADHD in relation to smoking status.

Methods: Patients (n422) were evaluated in the adult ADHD outpatient clinic of Hospital de Clínicas de Porto Alegre. Diagnoses were based on DSM-IV criteria and interviews were performed with Portuguese version of K-SADS-E for ADHD and Oppositional-Defiant Disorder. Axis I psychiatric comorbidities were evaluated with the SCID-I and smoking behavior with Fagerström Test for Nicotine Dependence (FTND). Personality was evaluated with Cloninger's Temperament and Character Inventory (TCI).

Results: The presence of smoking was strongly associated with externalizing characteristics as antisocial personality disorder (OR4.2) and substance dependence (OR6.5), but not with internalizing disorders. Moreover, smoking was associated with higher novelty seeking and lower harm avoidance scores.

Conclusions: Smoking initiation among patients with ADHD is consistent with a behavioral disinhibition profile beyond the possible role of self-medication in smoking persistence. Smoking in these patients is strongly associated with externalizing comorbid disorders.