Findings of a new study have showed that smoking is linked to increased risk of psychosis. Smokers often say that smoking helps them reduce stress. However, researchers at King's College London say that smoking may be a causal factor in itself.

The researchers added, “Schizophrenia patients are more likely to smoke because they use cigarettes as a form of self-medication to ease the distress of hearing voices or having hallucinations”.

They say that smoking can’t be said simply a case of self-medication if tobacco was used at a higher rare before the diagnosis of schizophrenia. Published in the Lancet Psychiatry, the study claimed the brain function is altered by nicotine present in cigarette smoke. The study was a meta-analysis of 61 separate studies, including almost 15,000 tobacco users and 273,000 non-users.

The researchers said smoking can increase three-fold risk of developing mental illnesses. The study showed that smokers accounted for more than 57% of people who had arrived at mental health services with their first episode of psychosis. The study found that likelihood of these patients to consume tobacco was three times higher than individuals without severe mental illness.

The study also showed that smokers became psychotic around a year earlier than those who didn’t smoke.

Dr. James MacCabe, one of the researchers from the Institute of Psychiatry, Psychology and Neuroscience at King's, said smokers should give up the habit as it’s linked to psychosis development. Excessive level of dopamine in the brain could trigger psychosis, say experts.