Publications by authors named "Evon B Lee"

Pseudohypoparathyroidism 1A (PHP1A) is a rare, genetic disorder. Most patients with PHP1A have cognitive impairment but this has not been systematically studied. We hypothesized that children with PHP1A would have lower intelligent quotient (IQ) scores than controls.

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Background: A small percentage of people with autism spectrum disorders (ASD) have alterations in chromosome 15q11.2-q3, the critical region for Prader-Willi syndrome (PWS). Data are limited, however, on the rates and characteristics of ASD in PWS.

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Based upon checklist data from the Autism Speaks Autism Treatment Network, we hypothesized that functional constipation (FC) would be associated with rigid-compulsive behavior in children with autism spectrum disorder (ASD). We used the Questionnaire on Pediatric Gastrointestinal Symptoms-Rome III to assess FC symptoms in 108 children with ASD. As hypothesized, FC was associated with parent ratings on the Repetitive Behavior Scales-Revised (RBS-R) Compulsive, Ritualistic, and Sameness subscales in the overall population.

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Autism spectrum disorder (ASD) is often accompanied by gastrointestinal disturbances, which also may impact behavior. Alterations in autonomic nervous system functioning are also frequently observed in ASD. The relationship between these findings in ASD is not known.

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Many children and adolescents with autism spectrum disorder (ASD) have significant gastrointestinal (GI) symptoms, but the etiology is currently unknown. Some individuals with ASD show altered reactivity to stress and altered immune markers relative to typically-developing individuals, particularly stress-responsive cytokines including tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6). Acute and chronic stress is associated with the onset and exacerbation of GI symptoms in those without ASD.

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Elevated whole blood serotonin levels are observed in more than 25% of children with autism spectrum disorder (ASD). Co-occurring gastrointestinal (GI) symptoms are also common in ASD but have not previously been examined in relationship with hyperserotonemia, despite the synthesis of serotonin in the gut. In 82 children and adolescents with ASD, we observed a correlation between a quantitative measure of lower GI symptoms and whole blood serotonin levels.

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Based on clinical experience, we hypothesized that rigid-compulsive behaviors are associated with severe constipation and co-occurring diarrhea or underwear staining in children with autism spectrum disorder. Using data from the Autism Treatment Network, we evaluated the association between these gastrointestinal symptoms and measures of rigid compulsive behavior in children ages 2-17. Following statistical correction, four of five primary measures were significantly associated with constipation and diarrhea or underwear staining, including parental report of repetitive behavior, parental report of compulsive behavior, clinician diagnosis of obsessive-compulsive disorder, and report of rituals observed on the autism diagnostic observation schedule.

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Etiology is unknown in the majority of individuals with autism spectrum disorder (ASD). One strategy to investigate pathogenesis is to stratify this heterogeneous disorder based on a prominent phenotypic feature that enriches for homogeneity within population strata. Co-occurring gastrointestinal dysfunction (GID) characterizes a subset of children with ASD.

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The objectives of this study were to characterize gastrointestinal dysfunction (GID) in autism spectrum disorder (ASD), to examine parental reports of GID relative to evaluations by pediatric gastroenterologists, and to explore factors associated with GID in ASD. One hundred twenty-one children were recruited into three groups: co-occurring ASD and GID, ASD without GID, and GID without ASD. A pediatric gastroenterologist evaluated both GID groups.

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Later-born siblings of children with Autism Spectrum Disorders (ASD) are at increased risk for ASD as well as qualitatively similar traits not meeting clinical cutoffs for the disorder. This study examined age five neurocognitive and behavioral outcomes of 39 younger siblings of children with ASD (Sibs-ASD) and 22 younger siblings of typically developing children (Sibs-TD) previously assessed in a longitudinal investigation starting in the second year of life. There were few group differences between Sibs-TD and Sibs-ASD on global measures of IQ, language, or behavior problems.

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Autism is a complex neurodevelopmental disorder diagnosed by impairments in social interaction, communication, and behavioral flexibility. Autism is highly heritable, but it is not known whether a genetic risk factor contributes to all three core domains of the disorder or autism results from the confluence of multiple genetic risk factors for each domain. We and others reported previously association of variants in the gene encoding the MET receptor tyrosine kinase in five independent samples.

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