Low prevalence of smoking in patients with autism spectrum disorders

Psychiatric patients are significantly more often smokers than the general population, the only known exception being obsessive–compulsive disorder (OCD) and catatonic schizophrenia. We have investigated nicotine use in subjects with autism spectrum disorders (ASD). Ninety-five subjects (25 females and 70 males) consecutively diagnosed with any ASD and of normal intelligence were included in the study. Only 12.6% were smokers, compared with 19% in the general population and 47% in a control group of 161 outpatients diagnosed with schizophrenia or a schizophreniform disorder. The results suggest that smoking is rare among subjects with ASD, while the opposite was shown for schizophrenia. If replicated, this finding could suggest biological differences between non-catatonic schizophrenia and ASD, and support the theory of a biological link between ASD and a subtype of OCD, and between ASD and catatonic schizophrenia.