title: Profile of refractive errors in European Caucasian children with Autistic Spectrum Disorder; increased prevalence and magnitude of astigmatism.
abstract: Autistic Spectrum Disorder (ASD) is a common neurodevelopmental disorder characterised by impairment of communication, social interaction and repetitive behaviours. Only a small number of studies have investigated fundamental clinical measures of vision including refractive error. The aim of this study was to describe the refractive profile of a population of children with ASD compared to typically developing (TD) children.
  
  
  
  Refractive error was assessed using the Shin-Nippon NVision-K 5001 open-field autorefractor following the instillation of cyclopentolate hydrochloride 1% eye drops.
  
  
  
  A total of 128 participants with ASD (mean age 10.9 ± 3.3 years) and 206 typically developing participants (11.5 ± 3.1 years) were recruited. There was no significant difference in median refractive error, either by spherical equivalent or most ametropic meridian between the ASD and TD groups (Spherical equivalent, Mann-Whitney U307 = 1.15, p = 0.25; Most Ametropic Meridian, U305 = 0.52, p = 0.60). Median refractive astigmatism was -0.50DC (range 0.00 to -3.50DC) for the ASD group and -0.50DC (Range 0.00 to -2.25DC) for the TD group. Magnitude and prevalence of refractive astigmatism (defined as astigmatism ≥1.00DC) was significantly greater in the ASD group compared to the typically developing group (ASD 26%, TD 8%, magnitude U305 = 3.86, p = 0.0001; prevalence (χ12=17.71 , p < 0.0001).
  
  
  
  This is the first study to describe the refractive profile of a population of European Caucasian children with ASD compared to a TD population of children. Unlike other neurodevelopmental conditions, there was no increased prevalence of spherical refractive errors in ASD but astigmatic errors were significantly greater in magnitude and prevalence. This highlights the need to examine refractive errors in this population.
authors.affiliation: Orthoptic Department, Royal Victoria Hospital, Belfast, UK.
authors.forename: Pamela M
authors.initials: PM
authors.lastname: Anketell
authors.affiliation: Vision Science Research Group, School of Biomedical Sciences, University of Ulster, Coleraine, UK.
authors.forename: Kathryn J
authors.initials: KJ
authors.lastname: Saunders
authors.affiliation: School of Psychology, University of Ulster, Coleraine, UK.
authors.forename: Stephen
authors.initials: S
authors.lastname: Gallagher
authors.affiliation: Community Paediatrics, Northern Health and Social Care Trust, Antrim, UK.
authors.forename: Clare
authors.initials: C
authors.lastname: Bailey
authors.affiliation: Vision Science Research Group, School of Biomedical Sciences, University of Ulster, Coleraine, UK.
authors.forename: Julie-Anne
authors.initials: JA
authors.lastname: Little
mesh_terms: D000293:Adolescent; D001251:Astigmatism / Q000150:complications / Q000208:ethnology* / Q000503:physiopathology; D001321:Autistic Disorder / Q000150:complications*; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D009660:Northern Ireland / Q000453:epidemiology; D015995:Prevalence; D012029:Refraction, Ocular / Q000502:physiology*; D014787:Vision Tests; D044465:White People
keywords: Autistic Spectrum Disorder; astigmatism; children; refractive error