Characteristics of sleep architecture in autism spectrum disorders: A meta-analysis based on polysomnographic research

Eleven parameters recorded by polysomnography were used to evaluate the differences in sleep structure between individuals with autism spectrum disorders (ASDs) and typically developed individuals (TDs). Four databases (PubMed, Web of Science, Cochrane Library, and China National Knowledge Infrastructure (CNKI)) were searched for potentially relevant literature published before July 14, 2019. Data extraction was performed by two independent assessors. The Cohen's d effect sizes and their 95% confidence intervals (CIs) were calculated to assess the effectiveness with the random-effects model. The heterogeneity was estimated by Cochran's Q test. The research yielded 14 case-control studies, 11 of which were included in this meta-analysis. Synthesis of the differences in 11 sleep parameters between individuals with ASDs and TDs demonstrated the pooled effect size of Cohen'd was -0.52 (95% CI: (-0.97, -0.08)) for total sleep time (TST), -0.69 (95% CI: (-1.27, -0.11)) for sleep efficiency (SE%) and 0.93 (95% CI: (0.37, 1.48)) for stage 1 sleep (S1%), respectively. Our findings suggested that compared with TDs, individuals with ASDs tend to have a decreased TST and SE% and an increased S1%. Differences of characteristics of sleep architecture in other sleep parameters between individuals with ASDs and TDs were not found in this study.