A new study published in the journal Psychological Medicine suggests that tobacco smoking can increase the risk for depression and schizophrenia.
Researchers at the University of Bristol analysed data from 462,690 individuals of European ancestry obtained through the UK Biobank. The individuals included eight per cent current smokers and 22 per cent former smokers. The authors employed the Mendelian randomisation approach which considers genetic variants associated with an exposure (e.g. smoking) to establish cause-and-effect relationships.
The findings showed that tobacco smoking was a significant risk factor for depression (OR, 1.99; 95% CI, 1.71-2.32; P<.001) and schizophrenia (OR, 2.27; 95% CI, 1.67-3.08; P<.001). Additionally, it was observed that depression and schizophrenia increased the odds for smoking; however, the evidence in this direction was weak for schizophrenia.
Dr Robyn Wootton, the lead author, said: "Individuals with mental illness are often overlooked in our efforts to reduce smoking prevalence, leading to health inequalities. Our work shows that we should be making every effort to prevent smoking initiation and encourage smoking cessation because of the consequences to mental health as well as physical health."
