Nicotine dependence and mental disorders among adults in the USA: evaluating the role of the mode of administration.

BACKGROUND: To investigate the association between nicotine dependence (ND), by cigarette smoking and use of smokeless tobacco (UST), and mental disorders.
METHOD: Face-to-face surveys (n=43 093) were conducted in the 2001-2002 National Epidemiologic Survey on Alcohol and Related Conditions (NESARC). Nicotine use, ND, and mental disorders were assessed using DSM-IV criteria.
RESULTS: UST-ND was associated with a significantly increased likelihood of any anxiety disorder, specific phobia, alcohol abuse and dependence. Consistent with previous findings, cigarette smoking-ND was associated with an increased likelihood of all mental disorders examined. Among those without ND, cigarette smoking was specifically associated with panic attacks and panic disorder; non-dependent UST was not associated with mental disorders.
CONCLUSIONS: Our findings suggest that the association between ND and mental disorders is relatively specific to the mode of nicotine administration. Among those who are nicotine dependent, cigarette use is associated with most major psychiatric disorders, whereas UST is associated with dysthymia and specific phobia. Among those who use tobacco but are not nicotine dependent, cigarette use is associated with dysthymia and panic disorder; UST is not associated with any major mood or anxiety disorders. The link between mental disorders and nicotine is complex, and is associated primarily with dependence, and not with non-dependent use.