There is a high prevalence of neuropsychiatric disorders in myotonic dystrophy types 1 and 2 (DM1 and DM2), including autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD) in DM1, and depression and anxiety in both DMs. The aim of this systematic review and meta-analysis was to estimate the prevalence of ASD, ADHD, depression and anxiety in the population with DM, and their association with disease onset. A systematic search of Medline, Scopus, Web of Science, and the Cochrane Library was conducted from inception to November 2023. Observational studies estimating the prevalence of these disorders in DM1 or DM2 were included. A meta-analysis of the prevalence of these disorders and an association study with disease onset by prevalence ratio meta-analysis were performed. Thirty-eight studies were included. In DM1, the prevalence of ASD was 14%, with congenital onset being 79% more common than juvenile onset, while the prevalence of ADHD was 21%, with no difference between congenital and juvenile onset, and the prevalence of depression and anxiety were 14% and 16%. Depression was more common in the adult onset. Finally, the prevalence of depression in DM2 was 16%. A higher prevalence of neuropsychiatric disorders is observed in individuals with DM1 and DM2 than in the general population. Therefore, actively screening for congenital and juvenile neurodevelopmental disorders in DM1 and emotional disorders in DM1 and DM2 may improve the quality of life of those affected.

Background: The muscular dystrophies are a heterogeneous group of genetic muscle diseases with variable distribution of weakness and mode of inheritance.Methods: We previously performed a systematic review of worldwide population-based studies on Duchenne and Becker muscular dystrophies; the current study focused on the epidemiology of other muscular dystrophies using Medline and EMBASE databases. Two reviewers independently reviewed all abstracts, full-text articles, and abstracted data from 1985 to 2011. Pooling of prevalence estimates was performed using random-effect models.Results: A total of 1104 abstracts and 167 full-text articles were reviewed. Thirty-one studies met all eligibility criteria and were included in the final analysis. The overall pooled prevalence of combined muscular dystrophies was 16.14 (confidence interval [CI], 11.21-23.23) per 100,000. The prevalence estimates per 100,000 were 8.26 (CI, 4.99-13.68) for myotonic dystrophy, 3.95 (CI, 2.89-5.40) for facioscapulohumeral dystrophy, 1.63 (CI, 0.94-2.81) for limb girdle muscular dystrophy, and 0.99 (CI, 0.62-1.57) for congenital muscular dystrophies.Conclusions: The studies differed widely in their approaches to case ascertainment, and substantial gaps remain in the global estimates of many other types of muscular dystrophies. Additional epidemiological studies using standardized diagnostic criteria as well as multiple sources of case ascertainment will help address the economic impact and health care burden of muscular dystrophies worldwide.