Prevalence and comorbidity of attention deficit hyperactivity disorder in Chinese school-attending students aged 6-16: a national survey.

Background: Attention deficit hyperactivity disorder (ADHD) is a prevalent neurodevelopmental disorder. Despite its significance, no large-scale epidemiological study assessing ADHD, and its associated comorbidities in children and adolescents has been conducted in China.

Methods: Within a national epidemiological survey of 73,992 children and adolescents aged between 6 and 16 in China, we used the CBCL, MINI-KID, and DSM-IV to identify ADHD and its comorbid conditions. Chi-square tests were utilized to compare the prevalence estimates across varied age and sex groups.

Results: The overall ADHD prevalence was estimated at 6.4% (95% CI: 6.2-7.0%). Broken down by subtypes, ADHD-I had a prevalence of 3.9%, ADHD-C was at 1.7%, and ADHD-H was at 0.9%. Boys and the younger age bracket recorded higher prevalence rates for ADHD and its subtypes (p < 0.001). Among ADHD-diagnosed individuals, 53% exhibited at least one comorbid psychiatric disorder. Oppositional defiant disorder/conduct disorder (ODD/CD) was the most prevalent comorbidity for ADHD-C and ADHD-H, at 58%, while anxiety disorders, at 17%, were predominant among ADHD-I cases. ODD/CD was notably higher among younger subjects (p < 0.001). In contrast, anxiety disorders were more frequent in older children and in girls (p < 0.001). Tic disorders showed a higher prevalence in younger boys, whereas mood and substance use disorders were more common in older boys (p < 0.001).

Conclusions: ADHD is a common neurodevelopmental disorder with high comorbidity rates that vary substantially across subtypes, age, and sex. These clinical heterogeneities complicate management and highlight the need for tailored interventions.