Epidemiology of Autism Spectrum Disorders

Department of Pediatrics and Human Development, Michigan State University College of Human Medicine and Kalamazoo Center for Medical Studies, 1000 Oakland Drive, Kalamazoo, MI 49008, USA.
Pediatric Clinics of North America (Impact Factor: 2.2). 02/2012; 59(1):27-43, ix-x. DOI: 10.1016/j.pcl.2011.10.003
Source: PubMed

ABSTRACT Epidemiologic data gathered over the last 40 years report that the conservative estimate of autistic spectrum disorder prevalence is 27.5 per 10,000 individuals; however, the prevalence estimate based on newer surveys is 60 per 10,000 individuals. Several factors are considered in various epidemiologic surveys of autism, especially the evolution of the concept of autism and changing criteria for diagnosis. This article reviews the incidence, prevalence, and risk factors for autism.

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    ABSTRACT: INTRODUCTION. In persons with autism spectrum disorders (ASD), aberrant sensory perceptions could be as characteristic and disruptive as the presence of anomalies in social communication and interaction or restricted and repetitive interests. Most of them present sensory modulation disorders (hyper- or hypo-responsiveness) in several sensory channels. Furthermore, there is a deficit in the integration of the information from a number of sensory systems (for example, auditory and visual). All this would worsen the core symptoms related with communication and increase the appearance of behavioural problems. AIMS. This study aims to review the experimental evidence that addresses the role played by the prefrontal cortex in unusual sensory experiences in ASD and its involvement in social aspects. There is evidence of hypoactivation and dysfunction of the neural networks, which include the prefrontal cortex and participate in social cognition, such as the default mode and the mirror neuron system in children with ASD. CONCLUSIONS. Sensory-motor problems at an early age correspond to a disruption in the organisation and regulation not only of perception and action but also language, thought, emotion and even memory.
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    ABSTRACT: This study evaluated the effects of a behavioral summer treatment program for children with high-functioning autism spectrum disorder (HFASD). Twenty boys (M = 9.2 years) diagnosed with HFASD participated in the 6-week program across 6 years. Detailed daily behavioral data were collected on a variety of positive and negative social behaviors. Repeated measures ANOVAs of weekly behavior frequencies indicated substantial improvements in a number of behaviors over the 6 weeks of the program, including following activity rules, contributing to a group discussion, paying attention, and less complaining/whining. Overall, results highlight the potential efficacy of treating chronic functional impairments of HFASD and associated problem behaviors in the context of an intensive behavioral summer treatment program.
    Journal of Autism and Developmental Disorders 12/2014; DOI:10.1007/s10803-014-2241-4 · 3.34 Impact Factor
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    ABSTRACT: It has been previously suggested that large amounts of oxalate in plasma could play a role in autism by binding to the bilobal iron transport protein transferrin (hTF), thereby interfering with iron metabolism by inhibiting the delivery of iron to cells. By examining the effect of the substitution of oxalate for the physiologically utilized synergistic carbonate anion in each lobe of hTF, we sought to provide a molecular basis for or against such a role. Our work clearly shows both qualitatively (6 M urea gels) and quantitatively (kinetic analysis by stopped-flow spectrofluorimetry) that the presence of oxalate in place of carbonate in each binding site of hTF does indeed greatly interfere with the removal of iron from each lobe (in the absence and presence of the specific hTF receptor). However, we also clearly demonstrate that once the iron is bound within each lobe of hTF, neither anion can displace the other. Additionally, as verified by urea gels and electrospray mass spectrometry, formation of completely homogeneous hTF–anion complexes requires that all iron must first be removed and hTF then reloaded with iron in the presence of either carbonate or oxalate. Significantly, experiments described here show that carbonate is the preferred binding partner; i.e., even if an equal amount of each anion is available during the iron loading process, the hTF–carbonate complex is formed.
    Biochemistry 11/2013; 52(46):8333–8341. DOI:10.1021/bi401190m · 3.19 Impact Factor