Association between sleep duration and attention-deficit hyperactivity disorder: A systematic review and...

Several previous meta-analyses have investigated the association between sleep quality and attention-deficit/hyperactivity disorder (ADHD). To examine the relationship between short or long sleep duration and ADHD, a meta-analysis of observational studies was conducted.

The PubMed, EMBASE, and Cochrane Library databases were systematically searched in March 2019 to retrieve observational studies. A random-effects model was used to analyze meta-estimates of sleep duration. Three evaluators independently reviewed and selected the articles based on pre-determined selection criteria.

Of 1466 articles retrieved, 10 observational epidemiological studies, comprising six case-control studies and four prospective cohort studies, were included in the final analysis. Short sleep duration was significantly linked to ADHD compared with average sleep duration (odds ratio [OR] or relative risk [RR] 1.28 [95% confidence interval (CI) 1.16-1.41]), and especially with hyperactivity (OR/RR 1.60 [95% CI 1.18-2.17]). Subgroup meta-analyses according to various factors, such as study design, number of participants, methodological quality, and adjustment for smoking status and education, yielded consistent results. A significant association between long sleep duration and ADHD was not observed.

Publication bias and substantial heterogeneity due to the diverse measurement tools used to determine ADHD were observed. Lack of prospective cohort studies was another limitation.

Short sleep duration was associated with ADHD in the current meta-analysis. Clinicians may need to be more aware of this association.