Examining the link between smoking and schizophrenia

Embargoed until 03 October 2012

A study examining the association between smoking and people with schizophrenia found that those with severe nicotine dependence tended to be prescribed higher doses of antipsychotic drugs and were more likely to be unemployed.

The research, published in today’s (1 October 2012) British Journal of Psychiatry, looked at 131 people with a diagnosis of schizophrenia in Nithsdale, Scotland, to try to assess the association between nicotine dependence and clinical symptoms. Seventy of those in the study were smokers, although 21 of the 61 non smokers had smoked in the past.

It found that those with severe nicotine dependence were likely to score higher on a scale measuring symptoms and were prescribed higher doses of antipsychotic.

Smoking rates among this group were twice as high as the general population in that part of Scotland, with the smokers in the study tending to be young men who were three times more likely to be unemployed than those in the general population.

The authors conclude that while their findings indicate an association between nicotine dependence, clinical symptoms and social adjustment, causal links cannot be inferred and further longitudinal studies are needed to explore the relationship.

They say: “Nicotine dependence was found to be associated with symptom severity and outcome in people with schizophrenia. Although our study does not establish a causal relationship between these variables, identifying and treating nicotine dependence may have some value in reducing morbidity and mortality in schizophrenia.”

References:

Krishnadas R, Juahar S, Telfer S, Shivashankar S and McCreadie RG. Nicotine dependence and illness severity in schizophrenia. British Journal of Psychiatry, 1 October 2012