Intensified testing for attention-deficit hyperactivity disorder (ADHD) in girls should reduce depression and smoking in adult females and the prevalence of ADHD in the longterm

Abstract

Attention-deficit hyperactivity disorder (ADHD) is the most common neurobehavioral disorder in youth. About a third to one-half of the affected subjects continue to have symptoms in adulthood. Remarkably, the prevalence numbers published for adult females are higher than for girls. The differences in the epidemiological data between the age groups clearly point to underdiagnosed ADHD in girls. Major depression, the most frequent psychiatric condition worldwide in adulthood, is twice as common in female as in male adults. Anxiety and depression are also among the most common comorbidities in adults with ADHD. Therefore, an undiagnosed ADHD may often underlie the psychopathology in depressive women. Another possibly associated phenomenon is the increased frequency of smoking in adult females. Since nicotine indirectly enhances the intrasynaptic dopamine level which presumably is too low both in ADHD and in depression, smoking might be used as a self-medication in women with untreated ADHD and consecutive depression. Furthermore, smoking during pregnancy is a major risk factor for ADHD in the offspring, so the vicious circle is complete. Depression in mothers of children with ADHD is associated with a higher rate of comorbidity in the children. Improved screening for ADHD in girls and treatment in childhood might thus reduce the rate of depression and smoking in adult females. We hypothesize that earlier identification and interventions might not only improve the lives of millions of girls and women but might also reduce the prevalence rates in future generations or at least moderate the deviant behaviour in this highly heritable disorder in which the development and severity of symptoms and the functional impairment depend to a high degree on epigenetic factors.