{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,14]],"date-time":"2026-10-14T10:16:25Z","timestamp":1791972985797,"version":"4.3.4"},"reference-count":64,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2021,10,27]],"date-time":"2021-10-27T00:00:00Z","timestamp":1635292800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Psychiatry"],"abstract":"<jats:p><jats:bold>Objective:<\/jats:bold> Individuals with autism spectrum disorder often present somatic and\/or psychiatric co-morbid disorders. The DSM-5 allows for consideration of additional diagnoses besides ASD and may have impacted the prevalence of co-morbidities as well as being limited in capturing the true differences in prevalence observed between males and females. We describe the prevalence of ASD and frequently observed co-morbidities in children and adolescents (&amp;lt;18 years) in the United States and five European countries.<\/jats:p><jats:p><jats:bold>Methods:<\/jats:bold> Two systematic literature reviews were conducted in PubMed and Embase for the period 2014\u20132019 and focusing on the prevalence of ASD and nine co-morbidities of interest based on their frequency and\/or severity: Attention Deficit Hyperactivity Disorder (ADHD), anxiety, depressive disorders, epilepsy, intellectual disability (ID), sleep disorders, sight\/hearing impairment\/loss, and gastro-intestinal syndromes (GI).<\/jats:p><jats:p><jats:bold>Results:<\/jats:bold> Thirteen studies on prevalence of ASD and 33 on prevalence of co-morbidities were included. Prevalence of ASD was 1.70 and 1.85% in US children aged 4 and 8 years respectively, while prevalence in Europe ranged between 0.38 and 1.55%. Additionally, current evidence is supportive of a global increase in ASD prevalence over the past years. Substantial heterogeneity in prevalence of co-morbidities was observed: ADHD (0.00\u201386.00%), anxiety (0.00\u201382.20%), depressive disorders (0.00\u201374.80%), epilepsy (2.80\u201377.50%), ID (0.00\u201391.70%), sleep disorders (2.08\u201372.50%), sight\/hearing impairment\/loss (0.00\u201314.90%\/0.00\u20134.90%), and GI syndromes (0.00\u201367.80%). Studies were heterogeneous in terms of design and method to estimate prevalence. Gender appears to represent a risk factor for co-morbid ADHD (higher in males) and epilepsy\/seizure (higher in females) while age is also associated with ADHD and anxiety (increasing until adolescence).<\/jats:p><jats:p><jats:bold>Conclusion:<\/jats:bold> Our results provide a descriptive review of the prevalence of ASD and its co-morbidities in children and adolescents. These insights can be valuable for clinicians and parents\/guardians of autistic children. Prevalence of ASD has increased over time while co-morbidities bring additional heterogeneity to the clinical presentation, which further advocates for personalized approaches to treatment and support. Having a clear understanding of the prevalence of ASD and its co-morbidities is important to raise awareness among stakeholders.<\/jats:p>","DOI":"10.3389\/fpsyt.2021.744709","type":"journal-article","created":{"date-parts":[[2021,10,27]],"date-time":"2021-10-27T07:11:26Z","timestamp":1635318686000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":303,"title":["Prevalence of Autism Spectrum Disorder and Co-morbidities in Children and Adolescents: A Systematic Literature Review"],"prefix":"10.3389","volume":"12","author":[{"given":"Cl\u00e9mence","family":"Bougeard","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fran\u00e7oise","family":"Picarel-Blanchot","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ramona","family":"Schmid","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rosanne","family":"Campbell","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jan","family":"Buitelaar","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2021,10,27]]},"reference":[{"key":"B1","year":"2018","journal-title":"Autism Spectrum Disorders in the European Union"},{"key":"B2","unstructured":"Diagnostic and Statistical Manual of Mental Disorders (DSM\u22125)2021"},{"key":"B3","unstructured":"Autism Spectrum Disorder: Warning Signs, Detection, Diagnosis and Assessment in Children and Adolescents2018"},{"key":"B4","doi-asserted-by":"publisher","first-page":"e20193447","DOI":"10.1542\/peds.2019-3447","article-title":"Identification, evaluation, and management of children with autism spectrum disorder","volume":"145","author":"Hyman","year":"2020","journal-title":"Pediatrics."},{"key":"B5","doi-asserted-by":"publisher","first-page":"274","DOI":"10.3390\/brainsci10050274","article-title":"Epidemiology of autism spectrum disorders: a review of worldwide prevalence estimates since 2014","volume":"10","author":"Chiarotti","year":"2020","journal-title":"Brain Sci."},{"key":"B6","doi-asserted-by":"publisher","first-page":"112922","DOI":"10.1016\/j.psychres.2020.112922","article-title":"Prevalence of comorbid psychiatric disorders among people with autism spectrum disorder: an umbrella review of systematic reviews and meta-analyses","volume":"287","author":"Hossain","year":"2020","journal-title":"Psychiatry Res."},{"key":"B7","doi-asserted-by":"publisher","first-page":"819","DOI":"10.1016\/S2215-0366(19)30289-5","article-title":"Prevalence of co-occurring mental health diagnoses in the autism population: a systematic review and meta-analysis","volume":"6","author":"Lai","year":"2019","journal-title":"Lancet Psychiatry."},{"key":"B8","doi-asserted-by":"publisher","first-page":"1065","DOI":"10.1177\/1362361318785171","article-title":"Delayed autism spectrum disorder recognition in children and adolescents previously diagnosed with attention-deficit\/hyperactivity disorder","volume":"23","author":"Kentrou","year":"2019","journal-title":"Autism."},{"key":"B9","doi-asserted-by":"publisher","first-page":"721","DOI":"10.1001\/jamapediatrics.2014.210","article-title":"Costs of autism spectrum disorders in the United Kingdom and the United States","volume":"168","author":"Buescher","year":"2014","journal-title":"JAMA Pediatr."},{"key":"B10","doi-asserted-by":"publisher","first-page":"389","DOI":"10.1177\/1362361320959959","article-title":"How do core autism traits and associated symptoms relate to quality of life? Findings from the Longitudinal European Autism Project","volume":"25","author":"Oakley","year":"2021","journal-title":"Autism."},{"key":"B11","doi-asserted-by":"publisher","first-page":"266","DOI":"10.1016\/j.ijchp.2016.03.001","article-title":"Psychiatric comorbidities in autism spectrum disorder: a comparative study between DSM-IV-TR and DSM-5 diagnosis","volume":"16","author":"Romero","year":"2016","journal-title":"Int J Clin Health Psychol."},{"key":"B12","doi-asserted-by":"publisher","first-page":"1698","DOI":"10.1007\/s10803-017-3413-9","article-title":"What about the girls? Sex-based differences in autistic traits and adaptive skills","volume":"48","author":"Ratto","year":"2018","journal-title":"J Autism Develop Diso."},{"key":"B13","doi-asserted-by":"publisher","first-page":"751","DOI":"10.3389\/fpsyt.2018.00751","article-title":"Characterizing the interplay between autism spectrum disorder and comorbid medical conditions: an integrative review","volume":"9","author":"Tye","year":"2018","journal-title":"Front Psychiatry."},{"key":"B14","unstructured":"Autism Data Visualization Tool2020"},{"key":"B15","doi-asserted-by":"publisher","first-page":"1","DOI":"10.15585\/mmwr.ss6802a1","article-title":"Prevalence and characteristics of autism spectrum disorder among children aged 4 years - early autism and developmental disabilities monitoring network, seven sites, United States, 2010, 2012, and 2014","volume":"68","author":"Christensen","year":"2019","journal-title":"MMWR Surv Summar"},{"key":"B16","doi-asserted-by":"publisher","first-page":"949","DOI":"10.1007\/s10803-019-04328-y","article-title":"Prevalence of autism spectrum disorder in 7-9-Year-Old children in Denmark, Finland, France and Iceland: a population-based registries approach within the ASDEU project","volume":"50","author":"Delobel-Ayoub","year":"2020","journal-title":"J Autism Dev Disord."},{"key":"B17","doi-asserted-by":"publisher","first-page":"e5","DOI":"10.1017\/S2045796018000483","article-title":"Prevalence of Autism Spectrum Disorder in a large Italian catchment area: a school-based population study within the ASDEU project","volume":"29","author":"Narzisi","year":"2018","journal-title":"Epidemiol Psychiatr Sci."},{"key":"B18","doi-asserted-by":"publisher","first-page":"3176","DOI":"10.1007\/s10803-018-3581-2","article-title":"Prevalence and characteristics of autism spectrum disorder among spanish school-age children","volume":"48","author":"Morales-Hidalgo","year":"2018","journal-title":"J Autism Dev Disord."},{"key":"B19","unstructured":"Mental Health of Children and Young People in England, 2017 [PAS]2018"},{"key":"B20","doi-asserted-by":"publisher","first-page":"283","DOI":"10.1177\/1362361316673977","article-title":"Diagnoses of autism spectrum disorders in Germany: Time trends in administrative prevalence and diagnostic stability","volume":"22","author":"Bachmann","year":"2018","journal-title":"Autism."},{"key":"B21","doi-asserted-by":"publisher","first-page":"1455","DOI":"10.1007\/s10803-018-3834-0","article-title":"Autism spectrum disorder: incidence and time trends over two decades in a population-based birth cohort","volume":"49","author":"Myers","year":"2019","journal-title":"J Autism Dev Disord."},{"key":"B22","article-title":"Recent age-specific prevalence and incidence time trends of autism spectrum disorder (ASD) in the United Kingdom (UK) using the clinical practice research datalink (CPRD)","author":"Yong","year":"2017","journal-title":"Pharmacoepidemiology and Drug Safety"},{"key":"B23","doi-asserted-by":"publisher","first-page":"3255","DOI":"10.1007\/s10803-015-2486-6","article-title":"Low but increasing prevalence of autism spectrum disorders in a French area from register-based data","volume":"45","author":"van Bakel","year":"2015","journal-title":"J Autism Dev Disord."},{"key":"B24","doi-asserted-by":"publisher","first-page":"e0124120","DOI":"10.1371\/journal.pone.0124120","article-title":"Trends in the prevalence of autism spectrum disorder, cerebral palsy, hearing loss, intellectual disability, and vision impairment, metropolitan atlanta, 1991-2010","volume":"10","author":"Van Naarden Braun","year":"2015","journal-title":"PLoS ONE."},{"key":"B25","doi-asserted-by":"publisher","first-page":"1011","DOI":"10.1007\/s00213-013-3140-7","article-title":"Pharmacological treatments prescribed to people with autism spectrum disorder (ASD) in primary health care","volume":"231","author":"Murray","year":"2014","journal-title":"Psychopharmacology"},{"key":"B26","doi-asserted-by":"crossref","first-page":"1","DOI":"10.15585\/mmwr.ss6904a1","article-title":"Prevalence of autism spectrum disorder among children aged 8 years - autism and developmental disabilities monitoring network, 11 sites, United States, 2016","volume":"69","author":"Maenner","year":"2020","journal-title":"MMWR Surv Summar"},{"key":"B27","doi-asserted-by":"publisher","first-page":"4103","DOI":"10.1007\/s10803-018-3670-2","article-title":"California autism prevalence trends from 1931 to 2014 and comparison to national ASD data from IDEA and ADDM","volume":"48","author":"Nevison","year":"2018","journal-title":"J Autism Dev Disord."},{"key":"B28","doi-asserted-by":"publisher","first-page":"645","DOI":"10.1111\/j.1469-7610.2000.tb02345.x","article-title":"The Development and well-being assessment: description and initial validation of an integrated assessment of child and adolescent psychopathology","volume":"41","author":"Goodman","year":"2000","journal-title":"J Child Psychol Psychiatry."},{"key":"B29","doi-asserted-by":"publisher","first-page":"3819","DOI":"10.1007\/s10803-019-04090-1","article-title":"Rates of co-occurring psychiatric disorders in autism spectrum disorder using the mini international neuropsychiatric interview","volume":"49","author":"Mosner","year":"2019","journal-title":"J Autism Dev Disord."},{"key":"B30","doi-asserted-by":"publisher","first-page":"2275","DOI":"10.1007\/s10803-017-3111-7","article-title":"Brief report: examining the association of autism and adverse childhood experiences in the national survey of children's health: the important role of income and co-occurring mental health conditions","volume":"47","author":"Kerns","year":"2017","journal-title":"J Autism Dev Disord."},{"key":"B31","doi-asserted-by":"publisher","first-page":"1201","DOI":"10.1177\/1362361318791279","article-title":"Prevalence of sensory impairments, physical and intellectual disabilities, and mental health in children and young people with self\/proxy-reported autism: Observational study of a whole country population","volume":"23","author":"Rydzewska","year":"2019","journal-title":"Autism."},{"key":"B32","doi-asserted-by":"publisher","first-page":"965","DOI":"10.1177\/1362361313505719","article-title":"Sex differences in co-occurring conditions of children with autism spectrum disorders","volume":"18","author":"Stacy","year":"2014","journal-title":"Autism."},{"key":"B33","doi-asserted-by":"publisher","first-page":"224","DOI":"10.1007\/s10803-016-2938-7","article-title":"Brief report: prevalence of co-occurring epilepsy and autism spectrum disorder: the U.S. national survey of children's health 2011-2012","volume":"47","author":"Thomas","year":"2017","journal-title":"J Autism Develop Diso"},{"key":"B34","doi-asserted-by":"publisher","first-page":"94","DOI":"10.1186\/s13073-015-0216-5","article-title":"An assessment of sex bias in neurodevelopmental disorders","volume":"7","author":"Polyak","year":"2015","journal-title":"Genome Med."},{"key":"B35","doi-asserted-by":"publisher","first-page":"1690","DOI":"10.1002\/aur.2040","article-title":"Psychiatric comorbidities and psychotropic medication use in autism: a matched cohort study with ADHD and general population comparator groups in the United Kingdom","volume":"11","author":"Houghton","year":"2018","journal-title":"Autism Res."},{"key":"B36","doi-asserted-by":"publisher","first-page":"52","DOI":"10.1016\/j.ridd.2016.11.009","article-title":"ADHD severity as it relates to comorbid psychiatric symptomatology in children with Autism Spectrum Disorders (ASD)","volume":"60","author":"Mansour","year":"2017","journal-title":"Res Dev Disabil."},{"key":"B37","doi-asserted-by":"publisher","first-page":"938","DOI":"10.1177\/1362361317712650","article-title":"Characterizing psychiatric comorbidity in children with autism spectrum disorder receiving publicly funded mental health services","volume":"22","author":"Brookman-Frazee","year":"2018","journal-title":"Autism."},{"key":"B38","doi-asserted-by":"publisher","first-page":"43","DOI":"10.3389\/fpsyt.2019.00043","article-title":"Prevalence and correlates of psychiatric symptoms in minimally verbal children and adolescents with ASD","volume":"10","author":"Plesa Skwerer","year":"2019","journal-title":"Front Psychiatry."},{"key":"B39","doi-asserted-by":"publisher","first-page":"2037","DOI":"10.1002\/aur.1848","article-title":"Psychiatric comorbidities and use of psychotropic medications in people with autism spectrum disorder in the United States","volume":"10","author":"Houghton","year":"2017","journal-title":"Autism Res."},{"key":"B40","doi-asserted-by":"publisher","first-page":"2283","DOI":"10.1007\/s10803-015-2361-5","article-title":"Co-occurring psychiatric disorders in preschool and elementary school-aged children with autism spectrum disorder","volume":"45","author":"Salazar","year":"2015","journal-title":"J Autism Dev Disord."},{"key":"B41","doi-asserted-by":"publisher","first-page":"778","DOI":"10.1002\/aur.1741","article-title":"The influence of sex and age on prevalence rates of comorbid conditions in autism","volume":"10","author":"Supekar","year":"2017","journal-title":"Autism Res."},{"key":"B42","doi-asserted-by":"publisher","first-page":"2663","DOI":"10.1007\/s10803-018-3521-1","article-title":"Prevalence of co-occurring medical and behavioral conditions\/symptoms among 4- and 8-year-old children with autism spectrum disorder in selected areas of the United States in 2010","volume":"48","author":"Soke","year":"2018","journal-title":"J Autism Dev Disord."},{"key":"B43","doi-asserted-by":"publisher","first-page":"107","DOI":"10.3389\/fpsyt.2019.00107","article-title":"Parental perspectives on psychiatric comorbidity in preschoolers with autism spectrum disorders receiving publicly funded mental health services","volume":"10","author":"Muratori","year":"2019","journal-title":"Front Psychiatry"},{"key":"B44","doi-asserted-by":"publisher","first-page":"e54","DOI":"10.1542\/peds.2013-0819","article-title":"Comorbidity clusters in autism spectrum disorders: an electronic health record time-series analysis","volume":"133","author":"Doshi-Velez","year":"2014","journal-title":"Pediatrics."},{"key":"B45","doi-asserted-by":"publisher","first-page":"1251","DOI":"10.1002\/aur.2132","article-title":"Epilepsy and autism severity: a study of 6,975 children","volume":"12","author":"Ewen","year":"2019","journal-title":"Autism Res."},{"key":"B46","doi-asserted-by":"publisher","first-page":"1272","DOI":"10.1002\/aur.2128","article-title":"Clustering of co-occurring conditions in autism spectrum disorder during early childhood: A retrospective analysis of medical claims data","volume":"12","author":"Vargason","year":"2019","journal-title":"Autism Res."},{"key":"B47","doi-asserted-by":"publisher","first-page":"248","DOI":"10.1016\/j.dld.2015.11.026","article-title":"Gastrointestinal symptoms and behavioral problems in preschoolers with Autism Spectrum Disorder","volume":"48","author":"Fulceri","year":"2016","journal-title":"Digest Liver Dis."},{"key":"B48","doi-asserted-by":"publisher","first-page":"501","DOI":"10.1002\/aur.1386","article-title":"Gastrointestinal dysfunction in children with autism spectrum disorders","volume":"7","author":"Kang","year":"2014","journal-title":"Autism Res."},{"key":"B49","doi-asserted-by":"publisher","first-page":"967","DOI":"10.1111\/jar.12590","article-title":"Impact of multiple co-occurring emotional and behavioural conditions on children with autism and their families","volume":"32","author":"Dovgan","year":"2019","journal-title":"J Appl Res Intellect Disabil."},{"key":"B50","doi-asserted-by":"publisher","first-page":"1552","DOI":"10.1016\/j.rasd.2014.08.006","article-title":"The effect of intellectual disability on the presence of comorbid symptoms in children and adolescents with autism spectrum disorder","volume":"8","author":"Goldin","year":"2014","journal-title":"Res Autism Spectr Disord."},{"key":"B51","doi-asserted-by":"publisher","first-page":"771","DOI":"10.1002\/aur.1492","article-title":"Patterns of risk for multiple co-occurring medical conditions replicate across distinct cohorts of children with autism spectrum disorder","volume":"8","author":"Aldinger","year":"2015","journal-title":"Autism Res"},{"key":"B52","doi-asserted-by":"publisher","first-page":"377","DOI":"10.1097\/DBP.0000000000000248","article-title":"Prevalence of diagnosed sleep disorders and related diagnostic and surgical procedures in children with autism spectrum disorders","volume":"37","author":"Elrod","year":"2016","journal-title":"J Develop Behav Pediatr."},{"key":"B53","doi-asserted-by":"publisher","first-page":"579","DOI":"10.1007\/s00787-020-01539-y","article-title":"The ASDEU autism prevalence study in northern Spain","volume":"30","author":"Fuentes","year":"2021","journal-title":"Eur Child Adolesc Psychiatry."},{"key":"B54","doi-asserted-by":"publisher","first-page":"1143","DOI":"10.1111\/jcpp.12913","article-title":"The development of autistic social traits across childhood and adolescence in males and females","volume":"59","author":"Mandy","year":"2018","journal-title":"J Child Psychol Psychiatry."},{"key":"B55","doi-asserted-by":"publisher","first-page":"22","DOI":"10.1038\/479022a","article-title":"The prevalence puzzle: autism counts","volume":"479","author":"Weintraub","year":"2011","journal-title":"Nature."},{"key":"B56","doi-asserted-by":"publisher","first-page":"292","DOI":"10.1001\/jamapsychiatry.2013.3893","article-title":"Potential impact of DSM-5 criteria on autism spectrum disorder prevalence estimates","volume":"71","author":"Maenner","year":"2014","journal-title":"JAMA Psychiatry."},{"key":"B57","doi-asserted-by":"publisher","DOI":"10.1007\/s10803-021-04904-1","article-title":"The diagnosis of autism: from kanner to DSM-III to DSM-5 and beyond","author":"Rosen","year":"2021","journal-title":"J Autism Dev Disord."},{"key":"B58","doi-asserted-by":"publisher","first-page":"1520","DOI":"10.1007\/s10803-018-3701-z","article-title":"Parent and teacher reports of comorbid anxiety and ADHD symptoms in children with ASD","volume":"50","author":"Llanes","year":"2020","journal-title":"J Autism Dev Disord."},{"key":"B59","doi-asserted-by":"publisher","first-page":"996","DOI":"10.1177\/1362361313508027","article-title":"The association between epilepsy and autism symptoms and maladaptive behaviors in children with autism spectrum disorder","volume":"18","author":"Viscidi","year":"2014","journal-title":"Autism."},{"key":"B60","doi-asserted-by":"publisher","first-page":"232","DOI":"10.1192\/bjp.bp.114.160192","article-title":"Premature mortality in autism spectrum disorder","volume":"208","author":"Hirvikoski","year":"2016","journal-title":"Br J Psychiatry"},{"key":"B61","doi-asserted-by":"publisher","first-page":"251","DOI":"10.1093\/ptj\/pzy006","article-title":"Associations of gross motor delay, behavior, and quality of life in young children with autism spectrum disorder","volume":"98","author":"Hedgecock","year":"2018","journal-title":"Phys Ther."},{"key":"B62","doi-asserted-by":"publisher","first-page":"25","DOI":"10.1007\/s10862-019-09748-9","article-title":"Screening for autism spectrum disorder with the achenbach system of empirically based assessment scales","volume":"42","author":"Deckers","year":"2020","journal-title":"J Psychopathol Behav Assess."},{"key":"B63","doi-asserted-by":"crossref","first-page":"675","DOI":"10.1007\/978-0-387-79948-3_1534","article-title":"Conners 3rd Edition (Conners 3 Conners 2008)","volume-title":"Encyclopedia of Clinical Neuropsychology.","author":"Conners","year":"2011"},{"key":"B64","doi-asserted-by":"publisher","first-page":"e80247","DOI":"10.1371\/journal.pone.0080247","article-title":"The strengths and difficulties questionnaire as a predictor of parent-reported diagnosis of autism spectrum disorder and attention deficit hyperactivity disorder","volume":"8","author":"Russell","year":"2013","journal-title":"PLoS ONE."}],"container-title":["Frontiers in Psychiatry"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fpsyt.2021.744709\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,10,27]],"date-time":"2021-10-27T07:11:33Z","timestamp":1635318693000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fpsyt.2021.744709\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,10,27]]},"references-count":64,"alternative-id":["10.3389\/fpsyt.2021.744709"],"URL":"https:\/\/doi.org\/10.3389\/fpsyt.2021.744709","relation":{},"ISSN":["1664-0640"],"issn-type":[{"value":"1664-0640","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,10,27]]},"article-number":"744709"}}