Autism at 70--redrawing the boundaries.
ABSTRACT Though the DSM-5 definition of autism refers to it as a spectrum, in important ways it represents an effort to define the syndrome more sharply. It thus reflects one of the central themes in the history of autism: a debate over where to set its boundaries. This year's revision of the diagnostic criteria for autism is among the most contentious of any in the new Diagnostic and Statistical Manual of Mental Disorders (the fifth edition, or DSM-5), provoking widespread fears among parents and advocacy groups that children who have received a diagnosis of autism will lose their eligibility for services. Coincidentally, this year also marks the 70th anniversary of psychiatrist Leo Kanner's first clinical description of autism in 1943.(1) Though the DSM-5 definition explicitly refers to autism as a spectrum, in important ways it represents an effort to define the syndrome more sharply. In this respect, ...
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ABSTRACT: Attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) are both frequently comorbid with other psychiatric disorders, but the comorbid effect of ASD and ADHD relative to the comorbid risk of other psychiatric disorders is still unknown. Using the Taiwan National Health Insurance Research Database, 725 patients with ASD-alone, 5694 with ADHD-alone, 466 with ASD + ADHD, and 27,540 (1:4) age-/gender-matched controls were enrolled in our study. The risk of psychiatric comorbidities was investigated. The ADHD + ASD group had the greatest risk of developing schizophrenia (hazard ratio [HR]: 95.89; HR: 13.73; HR: 174.61), bipolar disorder (HR: 74.93; HR: 19.42; HR: 36.71), depressive disorder (HR: 17.66; HR: 12.29; HR: 9.05), anxiety disorder (HR: 49.49; HR: 50.92; HR: 14.12), disruptive behavior disorder (HR: 113.89; HR: 93.87; HR: 26.50), and tic disorder (HR: 8.95; HR: 7.46; HR: 4.87) compared to the ADHD-alone, ASD-alone, and control groups. Patients with ADHD + ASD were associated with the greatest risk of having comorbid bipolar disorder, depressive disorder, anxiety disorder, disruptive behavior disorder, and tic disorder. The diagnoses of ASD and ADHD preceded the diagnoses of other psychiatric comorbidities. A comprehensive interview scrutinizing the psychiatric comorbidities would be suggested when encountering and following patients with both ASD and ADHD in clinical practice.Research in Autism Spectrum Disorders 11/2014; DOI:10.1016/j.rasd.2014.10.014 · 2.96 Impact Factor
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ABSTRACT: Abstract The papers on early identification and early intervention for autism spectrum disorders (ASD) in this scientific forum (published in volume 16(1) International Journal of Speech-Language Pathology) raise many important points, including describing the substantial progress made to date as well as analyses of current gaps and weaknesses in the existing evidence base. It is humbling to see the collective expertise of the distinguished authors contributing to this scientific forum including interdisciplinary perspectives and it is not surprising that there is ongoing debate on this important topic. In addition to discussing the points raised by these authors, this paper considers the implications of the new diagnostic criteria for ASD and for social communication disorder (SCD) in the Diagnostic and Statistical Manual of Mental Disorders-5 (DSM-5) in the US. Differential diagnosis of ASD and SCD will be paramount in testing early intervention for ASD and the expertise of speech-language pathologists in identifying SCD in infants and toddlers will be a central feature of discovery for both early identification and for early intervention in the decades to come. Finally, a biomedical example on testing early intervention on a spectrum disorder, derived from diabetes, is presented to illustrate both the promise and the pitfalls in testing interventions in the absence of well-validated assessment and intervention paradigms.International Journal of Speech-Language Pathology 02/2014; 16(1):61-8. DOI:10.3109/17549507.2013.864708 · 1.41 Impact Factor
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ABSTRACT: There has been a surge of diagnosis of autism spectrum disorders (ASD) over the past decade. While large, high powered genome screening studies of children with ASD have identified numerous genetic risk factors, research efforts to understanding how each of these risk factors contributes to the development autism has met with limited success. Revealing the mechanisms by which these genetic risk factors affect brain development and predispose a child to autism requires mechanistic understanding of the neurobiological changes underlying this devastating group of developmental disorders at multifaceted molecular, cellular and system levels. It has been increasingly clear that the normal trajectory of neurodevelopment is compromised in autism, in multiple domains as much as aberrant neuronal production, growth, functional maturation, patterned connectivity, and balanced excitation and inhibition of brain networks. Many autism risk factors identified in humans have been now reconstituted in experimental mouse models to allow mechanistic interrogation of the biological role of the risk gene. Studies utilizing these mouse models have revealed that underlying the enormous heterogeneity of perturbed cellular events, mechanisms directing synaptic and circuit assembly may provide a unifying explanation for the pathophysiological changes and behavioral endophenotypes seen in autism, although synaptic perturbations are far from being the only alterations relevant for ASD. In this review, we discuss synaptic and circuit abnormalities obtained from several prevalent mouse models, particularly those reflecting syndromic forms of ASD that are caused by single gene perturbations. These compiled results reveal that ASD risk genes contribute to proper signaling of the developing gene networks that maintain synaptic and circuit homeostasis, which is fundamental to normal brain development.02/2014; 9(2):137-150. DOI:10.1007/s11515-014-1298-y