ASSOCIATIONS BETWEEN CHILDHOOD ASTHMA AND ADHD - ISSUES OF PSYCHIATRIC COMORBIDITY AND FAMILIALITY

Objective: In this paper we evaluate the association between asthma an d attention-deficit hyperactivity disorder (ADHD), addressing issues o f comorbidity and familiality by formulating and testing competing hyp otheses. Method: Subjects were 6- to 17-year-old boys with DSM-III-R A DHD (N = 140) and normal controls (N = 120) and their first-degree rel atives. Information on asthma was obtained from the mothers in a stand ardized manner blind to the proband's clinical status. Results: The ri sk for asthma did not meaningfully differ between ADHD and control chi ldren. Relatives of ADHD probands with and without asthma were at sign ificantly greater risk for ADHD than relatives of normal controls. In contrast, the risk for asthma was significantly elevated only among re latives of children with ADHD plus asthma. Conclusions: These findings argue against a substantial etiological or pathophysiological relatio nship between the two conditions but suggest that ADHD and asthma are independently transmitted in families. Thus, the observation of ADHD s ymptoms in an asthmatic child should not be dismissed out of hand as b eing a consequence of asthma since many asthmatic ADHD children may ac tually have ADHD.