Direct family members of people with schizophrenia are more likely to smoke cigarettes compared to individuals with no family history of the disorder, according to a new study.
The researchers also discovered that the smoking family members of schizophrenia patients exhibit stronger signs of nicotine dependence than other smokers.
“Our results provide support for the hypothesis that familial factors increase the prevalence of smoking in first-degree relatives of schizophrenic subjects, who have a ‘high genetic risk’ of schizophrenia,” said Franck Schürhoff and his research team.
“If it can be confirmed that genetic factors make people at risk of schizophrenia more likely to smoke, this would have major implications for our understanding of the etiology of schizophrenia,” they added.
The study included 98 first-degree relatives of schizophrenia patients and 110 mentally healthy controls with no family history of the disorder. The mean age of the relatives was higher than that of controls, at 51.7 versus 41.9 years, but there were no significant differences regarding gender ratios or education levels.
The study participants were interviewed regarding their smoking habits. Nicotine dependence was assessed using the Fagerström Test for Nicotine Dependence (FTND). They were also assessed for schizotypal dimensions using the Schizotypal Personality Questionnaire (SPQ).
The findings revealed that families smoked nearly twice as much among relatives of schizophrenia patients — nearly 45 percent — versus the healthy control families (23.6 percent).
Furthermore, among all the smokers, the relatives of schizophrenia patients had greater levels of nicotine dependence than the control group.
“The relatives of schizophrenic patients are at a greater risk of becoming cigarette smokers. They therefore also have a greater risk of developing chronic health problems.
“Efforts should therefore be made to prevent nicotine dependence in these relatives and, if necessary, to help them quit smoking if they have already started,” said Schürhoff and team.
“As some studies have suggested that nicotine may play a role in conversion to psychosis and that heavier smoking is associated with a greater risk of schizophrenia, special psychiatric monitoring could be proposed for young heavy smokers related to schizophrenic subjects, who are at a greater risk of developing schizophrenia,” they added.
Source: Psychiatry Research