The inference of the new research, undertaken at King’s College London, is that those who smoke tobacco are more likely to develop schizophrenia at a younger age compared with non-smokers. The finding is based on an overview project (meta-analysis) that has examined 61 separate studies. This encompassed 14,555 smokers and 273,162 non-smokers. Drawing these together the research group conclude that nicotine in cigarette smoke could be capable of altering the brain.
In one sense the finding is not new. There has long been and association between people diagnosed with schizophrenia and smoking, with far more schizophrenia patients smoking than not. However, scientists though that those with schizophrenia turned to smoking to help deal with the anxiety or depression that led them to hear voices. Turning this on its head, the new research infers that smoking could be triggering schizophrenia in some people.
Schizophrenia is a mental disorder, characterized by difficult social behavior as well as a failure to recognize what is real and what is not. Typical symptoms include false beliefs, unclear or confused thinking, hearing hallucinations, reduced social engagement and depression.
The overall finding, the Daily Telegraph reports, was that those who smoke daily are twice as likely to develop schizophrenia compared with non-smokers. Furthermore, when comparing two sets of the population who could end up developing schizophrenia, those who smoke develop schizophrenia a year earlier than those who do not smoke.
The results remain associative rather than causative; nonetheless, the findings suggest that further research should be considered. Dr James MacCabe (Institute of Psychiatry, Psychology and Neuroscience) explained to BBC News: “It’s very difficult to establish causation [with this style of study], what we’re hoping that this does is really open our eyes to the possibility that tobacco could be a causative agent in psychosis, and we hope this will then lead to other research and clinical trials that would help to provide firmer evidence.”
The findings have been published in the medical journal Lancet Psychiatry. The study is titled “Does tobacco use cause psychosis? Systematic review and meta-analysis.”
