Division of Autism, State Diagnostic and Counselling Centre, Kopavogur, Iceland.
BMJ Open. 2013 Jun 20;3(6):e002748. doi: 10.1136/bmjopen-2013-002748.
A steady increase in the prevalence of autism spectrum disorders (ASD) has been reported in studies based on different methods, requiring adjustment for participation and missing data. Recent studies with high ASD prevalence rates rarely report on co-occurring medical conditions. The aim of the study was to describe the prevalence of clinically confirmed cases of ASD in Iceland and concomitant medical conditions.
The cohort is based on a nationwide database on ASD among children born during 1994-1998.
A total of 267 children were diagnosed with ASD, 197 boys and 70 girls. Only clinically confirmed cases were included. All received physical and neurological examination, standardised diagnostic workup for ASD, as well as cognitive testing. ASD diagnosis was established by interdisciplinary teams. Information on medical conditions and chromosomal testing was obtained by record linkage with hospital registers.
Two tertiary institutions in Iceland. The population registry recorded 22 229 children in the birth cohort.
Prevalence of all ASD was 120.1/10 000 (95% CI 106.6 to 135.3), for boys 172.4/10 000 (95% CI 150.1 to 198.0) and for girls 64.8/10 000 (95% CI 51.3 to 81.8). Prevalence of all medical conditions was 17.2% (95% CI 13.2 to 22.2), including epilepsy of 7.1% (95% CI 4.6 to 10.8). The proportion of ASD cases with cognitive impairment (intellectual quotient <70) was 45.3%, but only 34.1% were diagnosed with intellectual disability (ID). Children diagnosed earlier or later did not differ on mean total score on a standardised interview for autism.
The number of clinically verified cases is larger than in previous studies, yielding a prevalence of ASD on a similar level as found in recent non-clinical studies. The prevalence of co-occurring medical conditions was high, considering the low proportion of ASD cases that also had ID. Earlier detection is clearly desirable in order to provide counselling and treatment.
基于不同方法的研究报告称，自闭症谱系障碍（ASD）的患病率稳步上升，这需要对参与情况和缺失数据进行调整。最近一些 ASD 患病率较高的研究很少报告同时存在的医疗状况。本研究的目的是描述冰岛 ASD 临床确诊病例的患病率以及同时存在的医疗状况。
该队列基于一项针对 1994-1998 年期间出生的儿童的全国 ASD 数据库。
共有 267 名儿童被诊断为 ASD，其中 197 名男孩和 70 名女孩。仅纳入临床确诊病例。所有儿童均接受了身体和神经检查、ASD 标准诊断评估以及认知测试。ASD 诊断由跨学科团队确定。通过与医院登记册的记录链接获取医疗状况和染色体检测信息。
冰岛的两家三级医疗机构。人口登记册记录了该出生队列中有 22229 名儿童。
所有 ASD 的患病率为 120.1/10000（95%CI 106.6 至 135.3），男孩为 172.4/10000（95%CI 150.1 至 198.0），女孩为 64.8/10000（95%CI 51.3 至 81.8）。所有医疗状况的患病率为 17.2%（95%CI 13.2 至 22.2），包括癫痫的患病率为 7.1%（95%CI 4.6 至 10.8）。有认知障碍（智商<70）的 ASD 病例比例为 45.3%，但仅有 34.1%被诊断为智力残疾（ID）。在标准化自闭症访谈的总得分均值上，较早或较晚诊断的 ASD 病例没有差异。
临床确诊病例的数量大于以往研究，ASD 的患病率与最近非临床研究中的患病率相当。同时存在医疗状况的比例较高，考虑到同时患有 ID 的 ASD 病例比例较低。显然，早期发现以便提供咨询和治疗是可取的。
