How effective are interventions for smoking cessation in schizophrenia?
Compared with placebo, bupropion increased smoking abstinence
rates in smokers with schizophrenia for up to six months (NNT*
17), without jeopardising their mental state. Expired carbon
monoxide (CO) level and the number of cigarettes smoked daily
were significantly lower with bupropion at the end of therapy but
not after six months. There were no significant differences in
positive, negative and depressive symptoms between bupropion
and placebo groups. There was no report of any major adverse
event, such as seizures, with bupropion use. One study showed
contingent reinforcement (CR) with money increased smoking
abstinence rates and reduced the level of smoking. However,
there was no evidence CR produced sustained results for these
outcomes in the longer term.
* NNT = number needed to treat to benefit one individual.
The strength of the evidence for bupropion was relatively weak
with wide confidence intervals, especially for longer-term benefit,
because of the small number of participants. There was no
evidence of benefit for the few trials of other pharmacological
therapies (including nicotine replacement therapy) and psychosocial
interventions, in helping smokers with schizophrenia to quit
or reduce smoking.
People with schizophrenia smoke more heavily than the general
population and this contributes to their higher morbidity and
mortality from smoking-related illnesses.