Copy number variations in Japanese children with autism spectrum disorder.

OBJECTIVE: Although autism spectrum disorder (ASD) occurs worldwide, most genomic studies on ASD were performed on those of Western ancestry. We hypothesized ASD-related copy number variations (CNVs) of Japanese individuals might be different from those of Western individuals. METHODS: Subjects were recruited from the Hirosaki 5-year-old children's developmental health check-up (HFC) between 2013 and 2016 (ASD group; n = 68, control group; n = 124). This study conducted CNV analysis using genomic DNA from peripheral blood of 5-year-old Japanese children. Fisher's exact test was applied for profiling subjects and CNV loci. RESULTS: Four ASD-related CNVs: deletion at 12p11.1, duplications at 4q13.2, 8p23.1 and 18q12.3 were detected (P = 0.015, 0.024, 0.009, 0.004, respectively). Specifically, the odds ratio of duplication at 18q12.3 was highest among the 4 CNVs (odds ratio, 8.13). CONCLUSIONS: Four CNVs: microdeletion at 12p11.1, microduplications at 4q13.2, 8p23.1 and 18q12.3 were detected as ASD-related CNVs in Japanese children in this study. Although these CNVs were consistent with several reports by Western countries at cytoband levels, these did not consistent at detailed genomic positions and sizes. Our data indicate the possibility that these CNVs are characteristic of Japanese children with ASD. We conclude that Japanese individuals with ASD may harbor CNVs different from those of Western individuals with ASD.

Prevalence of pathological and maladaptive Internet use and the association with depression and health-related quality of life in Japanese elementary and junior high school-aged children.

PURPOSE: Pathological Internet use has been predominantly studied in junior high/middle school-aged or older children; data from elementary/primary school-aged children, however, are scarce. The current study aimed to examine the prevalence of problematic Internet use, including pathological and maladaptive Internet use, in elementary and junior high school-aged children and the relationships between problematic Internet use and mental health problems and health-related quality of life. METHODS: The survey was conducted among children who attend national and public elementary and junior high schools in a medium-sized city in Japan; data were received from 3845 elementary school-aged and 4364 junior high school-aged children. RESULTS: Based on the Young's Diagnostic Questionnaire score, the prevalence of pathological and maladaptive Internet use was 3.6% and 9.4% and 7.1% and 15.8% in elementary and junior high school-aged children, respectively. The prevalence of problematic Internet use, including pathological and maladaptive Internet use, consistently increased from the 4th grade to the 8th grade. In addition, the prevalence sharply increased between the 7th grade and the 8th grade. Our study revealed that children with pathological and maladaptive Internet use exhibited more severe depression and decreased health-related quality of life than those with adaptive Internet use. CONCLUSIONS: Our results demonstrated that pathological Internet use is not uncommon even in elementary school-aged children and that those with pathological and maladaptive Internet use have severe mental health problems and decreased health-related quality of life, supporting the importance of providing these children with educational and preventive interventions against problematic Internet use and associated risk factors.

Correction: Adaptation of the Autism Spectrum Screening Questionnaire (ASSQ) to preschool children.

[This corrects the article DOI: 10.1371/journal.pone.0199590.].

Adaptation of the Autism Spectrum Screening Questionnaire (ASSQ) to preschool children.

The Autism Spectrum Screening Questionnaire (ASSQ) is equipped with good properties for screening the broader phenotype of autistic traits, but it is standardized for a limited age range-from 7 to 16 years. To contribute to the early detection of Autism Spectrum Disorder (ASD), particularly in high functioning children with ASD, likely to cause maladjustments during school age, the present study examined psychometric properties to apply the ASSQ to a younger age. We tested parents' ASSQ ratings for preschool children in clinical (N = 154, average age 60.77 months, range 55-72 months) and community settings (N = 1390, average age 60.53 months, range 57-68 months) in Japan. The results showed, just as in school-aged children, the ASSQ had reliability and validity as a screening instrument for preschool children in community settings. A cut-off of 7 with sensitivity of 0.93 and specificity of 0.84 is recommended for community screening. Still, based on the current study with a clinical group, an optimal cut-off score with high sensitivity and high specificity for parents' ASSQ ratings could not be established. The clinicians should be reminded that the ASSQ is a screening instrument, not a diagnosing instrument. Also, this result suggest multi-faceted evaluation is necessary in clinical settings, for example, the addition of teachers' ratings.

Coordination difficulties in preschool-aged children are associated with maternal parenting stress: A community-based cross-sectional study.

BACKGROUND: Although coordination difficulties are sometimes observed even in children in the general population, no empirical studies have examined the impact of these difficulties on parenting stress. AIMS: The aim of this study was to elucidate the relationship between coordination difficulties and parenting stress in a community-based sample of preschool-aged children and their mothers. METHODS: The study included 1691 families. Mothers with 4- or 5-year-old children completed questionnaires about parenting stress and children's coordination difficulties, as well as traits associated with attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). RESULTS: The results of hierarchical multiple regression analyses showed that coordination difficulties, and ADHD and ASD traits were each independent predictors of parenting stress. Among the significant predictive factors, impaired general coordination, as well as hyperactivity-impulsivity, showed a strong impact on parenting stress. In addition, a gender difference was observed in the manner in which coordination difficulties influenced parenting stress. CONCLUSIONS: Coordination difficulties in preschool-aged children in the general population increased maternal parenting stress (as did ADHD and ASD traits). This highlights the need to provide support for mothers who have children with coordination difficulties, even when there is no clinical diagnosis.

Prevalence of sleep problems in Japanese preschoolers in a medium-sized city: Community-based survey using the Children's Sleep Habits Questionnaire.

Although the mean score of the Children's Sleep Habits Questionnaire (CSHQ) differs between countries, there are no normative data for the CSHQ of Japanese preschoolers based on a community sample. The aims of this study were therefore to present normative data for the CSHQ and determine the prevalence and characteristics of sleep problems in Japanese preschoolers. Parents or the primary caregiver of 482 preschoolers aged 4-5 years completed the CSHQ and the Strength and Difficulties Questionnaire. Approximately 80% of preschoolers scored above the cut-off for sleep disturbance on the CSHQ. In addition, co-sleeping was prevalent in Japanese preschoolers but the habit of co-sleeping contributed little to behavioral and emotional problems. Sleep problems appear to be prevalent in Japanese preschoolers based on the CSHQ, and could be associated with the Japanese sleep habit of co-sleeping.

Psychometric properties of the Japanese ADHD-RS in preschool children.

BACKGROUND: Children with ADHD show multiple difficulties in their lives. Its early detection is important to provide timely intervention. AIMS: To evaluate the psychometric properties of the Japanese version of the home and school form of the ADHD-Rating Scale-IV (P- and T-ADHD-RS) for screening five-year-olds with ADHD. METHODS: The parents and teachers of 838 children (452 boys, 386 girls; including 28 boys, 18 girls diagnosed ADHD) completed the ADHD-RS and the Strengths and Difficulties Questionnaire in a community health check-up. RESULTS: The P- and T-ADHD-RS confirmed the two-factor model (Inattention and Hyperactivity-Impulsivity) and internal consistencies (CFI=0.968, 980; RMSEA=0.049, 0.055; SRMR=0.030, 0.024; α=0.86-.93). Japanese boys and girls scored significantly lower in all scales of the P- and T-ADHD-RS (d=0.65-1.14, 0.36-0.59) than US children. The P-ADHD-RS showed higher accuracy in area under the curve (AUC), sensitivity, and positive predictive value (PPV) than the T-ADHD-RS (AUC=0.955, 0.692; sensitivity=89.13%, 30.23%; PPV=46.59%, 16.05%). IMPLICATIONS: The P-ADHD-RS shows good reliability and validity for screening children with possible ADHD in a community. Longitudinal studies are needed to examine its predictive validity of adaptation in their lives at school.