How is smoking related to schizophrenia?
Tobacco smoking is very common among people with schizophrenia, who often have particularly heavy use. This poses considerable health risks, may interfere with antipsychotic medications, and may place a financial burden on the individual. Heavy cigarette use may contribute to the increased mortality and reduced life expectancy reported within the schizophrenia population. This topic considers the effects of smoking among people with schizophrenia. Please also see the smoking topic in comorbid conditions for the rates of smoking in this population.

What is the evidence for smoking in people with schizophrenia?

Moderate to high quality evidence found small effects of more severe positive symptoms and less severe extrapyramidal symptoms in smokers with schizophrenia compared to non-smokers with schizophrenia. There were no differences in negative symptoms, depression, anxiety, tardive dyskinesia, or parkinsonism.

Moderate quality evidence suggests the most commonly reported reasons for smoking were relaxation/stress reduction, dysphoria relief, sociability, craving/addiction. The most commonly reported reasons for quitting were self-control, health concerns, social influence. The following factors were identified as barriers to smoking cessation: cravings and addiction, perceived risk of negative affect, social pressures, stress and boredom reduction, and weight management. Knowledge about health risks of smoking, physician advice and social pressures to quit helped facilitate smoking cessation.

Craving scores were higher in people with schizophrenia and a substance use disorder (tobacco, cannabis, or cocaine) compared to people without schizophrenia and a substance use disorder. Scores were greater for relief (desire for the reduction of negative effects of withdrawal) than reward (desire for the rewarding effects of drugs).

There was a medium-sized effect of reduced clozapine blood levels in smokers compared to non-smokers with schizophrenia. Clozapine dose was higher in the smoking group; those who quit smoking could have clozapine dose decreased.

High quality evidence found small impairments in attention, working memory, learning, reasoning/problem solving, and speed of processing in smokers vs. non-smokers with schizophrenia. There were no differences in delayed memory, executive functioning (abstraction/shifting or inhibition), or language.

March 2022

mage: ©ehabeljean – Fotolia –

Last updated at: 2:44 pm, 28th March 2022
To view documentation related to this topic download the files below
Fact Sheet Technical Commentary
Tags:  Smoking

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