Medical Video: Schizophrenia & Smoking | Schizophrenia
Heavy smokers have long been associated with a risk of psychotic disorders that lead to schizophrenia. But whether smoking actually actually triggers or even treats the symptoms of schizophrenia, this still continues to be a heated debate among experts. Why is that?
Those who say smoking treats the symptoms of schizophrenia
A 2014 study by researchers from Washington University School of Medicine found that people with severe mental illness such as schizophrenia were five times more likely to become heavy smokers. This tendency was then further studied by a joint team of scientists from abroad, who explained that it was possible the nicotine content in cigarettes works to repair damaged brain areas due to symptoms of schizophrenia.
The root of their experiment is what is called hypofrontality. Hypofrontality is a decrease in activity in the brain's prefrontal cortex which leads to cognitive problems such as memory disorders and difficulty making decisions. By observing lab mice, scientists from the Pasteur Institute in Paris and from the University of Colorado showed that the genetic mutation of CHRNA5 (which was previously associated with an increased risk of symptoms of schizophrenia), was also associated with decreased function in the frontal lobe.
Disorders in the frontal lobe have been linked to problems of reasoning and problem solving, as well as self and emotional control. This disorder in two parts of the brain is suspected of triggering the symptoms of psychosis that refers to schizophrenia, such as hallucinations, delusions, and comprehension.
Researchers say nicotine reverses this problem, at least in mice, because nicotine affects receptors in certain brain regions to carry out healthy cognitive functions. When lab mice that showed symptoms of schizophrenia were given daily nicotine doses, brain activity that had been slow had shown improvement in two days. And in one week, said the researcher, brain activity returned to normal.
Basically, researchers suspect that nicotine works against the side effects of schizophrenia drugs or a decrease in brain cognitive function due to genetic defects of schizophrenia itself.
Those who argue that smoking actually triggers symptoms of schizophrenia
On the other hand, a review study published in the journal Lancet Psychiatry reported that people who smoke have a threefold increased risk of experiencing symptoms of schizophrenia than those who are not smokers.
The research team recycled the findings from 61 previous studies involving 15 thousand smokers and 273 thousand non-smokers. They found that almost 57% of patients who experienced the first episode of symptoms of schizophrenia were smokers. The researchers also found that heavy smokers displayed symptoms of schizophrenia on average one year faster than non-smokers.
These findings then shed doubt on the theory that the relationship between smoking and psychosis exists because schizophrenic patients use cigarettes as a way to treat themselves. Long story short, according to the research team, these people first developed routine smoking habits, only showed symptoms of schizophrenia as a result of smoking on their mental health.
Researchers suspect that dopamine plays a key role in the development of symptoms of schizophrenia. Excess dopamine is the best biological factor that the medical world has had to date to explain psychotic diseases such as schizophrenia. It is possible that nicotine increases dopamine release, which causes symptoms of schizophrenia to develop.
So, which one is right?
You could say, the way to determine the direction of cause and effect of the relationship between heavy smoking and symptoms of schizophrenia still has to be explored. Whichever result shows that smoking habits should still be considered serious risk factors that might play a role in developing psychotic symptoms and schizophrenia, and are not underestimated simply as a consequence of the disease. Thus many health experts say.
Instead, researchers urge that mental health professionals and health workers deal directly with schizophrenic patients to start encouraging them to stop smoking as a precautionary measure that is preferred.