Prevalence of attention-deficit hyperactivity disorder (ADHD) and comorbid psychiatric problems in children 12 years and younger: A systematic review and meta-analysis.

BACKGROUND

We aim to perform a systematic review and meta-analysis to synthesize current available evidence in the prevalence of attention-deficit hyperactivity disorder (ADHD) and its comorbid psychiatric problems in children 12 years and younger.

METHODS

We searched PubMed, Science Network, Embase, PsycINFO, and Scopus for original studies published in English from database inception to September 23, 2022. Based on strict quality assessment, studies of moderate to high quality were finally included. Random-effects models were used to estimate the pooled prevalence. Heterogeneity was evaluated by using a series of subgroup analysis stratified by key factors, together with meta-regressions. The study protocol is registered with PROSPERO (CRD42023398958).

RESULTS

24 studies were finally included and synthesized, with an overall pooled prevalence of 0.03 (95 % CI [0.02-0.05]) for ADHD in children 12 years and younger, the pooled prevalence for psychiatric comorbidities in ADHD children varied between 0.02 and 0.53. Oppositional defiant disorder (ODD) was the most common psychiatric comorbidity in children with inattentive subtype (ADHD-I, pooled prevalence of 0.27 [95 % CI 0.19-0.41]) and combined subtype (ADHD-C, pooled prevalence of 0.42 [95 % CI 0.30-0.59]). Subgroup analysis revealed that different diagnostic criteria and regions introduced prominent heterogeneity to pooled prevalence of ADHD and its psychiatric comorbidities.

CONCLUSION

Variation in prevalence of ADHD and its comorbid mental disorders was seen in children 12 years and younger of different characteristics. Tailored intervention measures need to be developed for ADHD children with co-occurring mental illnesses, who are of higher risk in negative outcomes.