OBJECTIVETo assess comorbidities and functional impairments in children with attention deficit hyperactivity disorder (ADHD), and to investigate their relationship with the core symptoms (attention deficit and hyperactivity) of ADHD.

METHODSA total of 319 children with suspected ADHD were included in the study. The Vanderbilt ADHD Parent Rating Scale (VADPRS) was completed by their parents. Diagnosis and classification were performed based on the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition. Comorbidities and functional impairments were evaluated according to the VADPRS. Children with various types of ADHD were compared in terms of comorbidities and functional impairments, and their relationship with the core symptoms of ADHD was analyzed.

RESULTSOf the 319 children, 196 were diagnosed with ADHD, including 84 cases of predominantly inattentive type (ADHD-I), 35 cases of predominantly hyperactive-impulsive type (ADHD-HI) and 77 cases of combined type (ADHD-C); 123 did not meet the diagnostic criteria for ADHD. At least one other psychiatric disorder (oppositional defiant disorder, conduct disorder or emotional disorder) was seen in 63.8% (125/196) of the children with ADHD, versus 37.4 % (46/123) of the children without ADHD (P<0.05). The incidence of oppositional defiant disorder and conduct disorder in the ADHD-C subgroup was significantly higher than in the ADHD-I subgroup (P<0.05). The sums of oppositional defiant disorder, conduct disorder and emotional disorder symptoms were weakly correlated with the sums of hyperactive-impulsive and inattentive symptoms (P<0.01). Up to 89.8% of children with ADHD and 74.8% of children without ADHD showed functional impairments (P<0.05). The ADHD-C subgroup had a significantly higher overall incidence of functional impairments than the ADHD-I and ADHD-HI subgroups (P<0.05). The sum of inattentive symptoms was weakly correlated with the scores of learning ability, sibling relationship and participation in organized activities (P<0.01), and the sum of hyperactive-impulsive symptoms was weakly correlated with the score of sibling relationship (P<0.01).

CONCLUSIONSThe incidence of comorbidities and functional impairments among children with ADHD is high, especially in those with ADHD-C. The severity of core symptoms in children with ADHD can influence the occurrence of comorbidities and functional impairments. The incidence of psychiatric disorders and functional impairments is also high in children with suspected ADHD who do not meet the diagnostic criteria for ADHD, so attention also needs to be paid to interventions among these children.