A Study on the Incidence and Comorbidities of Autism Spectrum Disorders Accompanied by Intellectual Disabilities in Yonago City, Japan

Abstract

Background Autism spectrum disorders (ASD) with intellectual disabilities may be associated with many factors. This study focused on patients with ASD with intellectual disabilities, defined by a threshold intelligence quotient (IQ) or development quotient (DQ) of 70. We also discuss comorbidities and other factors related to ASD. Method We extracted case records of patients born between April 1995 and March 2001 who lived in Yonago City, as of January 2011, and had visited the two specialist institutions for consultation regarding developmental issues. The list was further narrowed down to patients identified, as having ASD by pediatric neurologists based on Diagnostic and Statistical Manual of Mental Disorders (Fifth Edition) (DSM-5). We selected patients with < IQ/DQ 70 using the most recent intelligence/ development test to determine comorbidities and other factors related to ASD. Results The data of 81 patients (59 males and 22 females) were extracted, corresponding to an incidence of 76.2 patients out of every 10,000 births. The male-tofemale ratio was 2.7:1. Comorbidities and related factors of ASD were observed in 25 cases (30.9%). Eleven cases had perinatal abnormalities. Other abnormalities were observed in 17 cases, including epilepsies in 7, chromosomal abnormalities in 4, familial mental retardation in 1, and acquired brain injury in 1. Conclusion It is important to treat and support individuals with ASD and intellectual disabilities taking into account the characteristics and prognosis of the comorbidities and related factors.

Increased NMDARs in neurons and glutamine synthetase in astrocytes underlying autistic-like behaviors of Gabrb1−/− mice

“…This ALE network might explain the high rate of comorbidity among autism, intellectual disability, and epilepsy reported in the literature. 26 , 27 By looking at the differential expression of the 37 genes shared by the three sets of candidate genes in the ALE network, we found that the NMDAR subunit genes Grin1/2b , calcium channel Cacna1h , lysine-specific demethylase Kdm5c , and neuronal extracellular matrix glycoprotein Reln were up-regulated ( Figure 3 B). Cacna1h is reported to control NMDAR-mediated transmission, 28 the histone demethylase Kdm5c is required for synaptic structure and function, 3 and Reelin (encoded by Reln ) modulates NMDA receptor activity.…”

Increasing the Awareness of Autism Spectrum Disorder with Training of Pre-School Teachers and School Counselors in Turkey

“…43 To the field 4 item of "Autism spectrum disorder is more often accompanied by mental retardation in children," a response of "Yes " was given by 64.6% (n ¼ 146) of the preschool teachers and by 82.9% (n ¼ 68) of the school counselors (p ¼ 0.06) Coexistence of severe mental retardation and autism was reported as 32.1% in a study conducted in Japan. 44 To the item "Epilepsy is more common in children with autism spectrum disorder," a response of "Yes " was given by 77% (n ¼ 174) of the preschool teachers and by 90.2% (n ¼ 74) of the school counselors (p ¼ 0.010). In a study by Lukmanji et al, it was found that the prevalence of epilepsy in autism patients was higher than the normal population.…”