The prevalence of Autism Spectrum Disorder in Down Syndrome children attending the Child Development Centre in Universiti Kebangsaan Malaysia Medical Centre.

INTRODUCTION

The main objective of this study was to determine the prevalence of Autism Spectrum Disorder (ASD) in Down Syndrome (DS) children attending the DS clinic at Child Development Centre Universiti Kebangsaan Malaysia Medical Centre (CDC-UKMMC) and to assess the appropriateness of using an M-CHAT as an ASD screener in this population. We traced the karyotype results of our study population from their medical record and compared this to study participant with a dual diagnosis of Down Syndrome- Autism Spectrum Disorder (DS-ASD). Lastly, we assessed the awareness among parents attending our DS follow up clinic regarding the possibility of an ASD diagnosis in DS children.

MATERIALS AND METHODS

This a single-centre cross-sectional study among DS children aged 18-60 months who attend the DS follow up clinic in UKMMC. Overall, 24 children were recruited to our study. The accompanying parent was given the Modified Checklist for Autism in Toddlers (M-CHAT) questionnaire and a data collection sheet prior to their consultation. The chromosomal study was traced from their medical case notes. Children that were eligible for the study had their development assessed using the tool Schedule of Growing Skills II. The diagnosis of ASD was determined by the attending paediatrician using The Diagnostic and Statistical Manual of Mental Disorders 5 (DSM-5) criteria.

RESULTS

The prevalence of dual diagnoses DS-ASD in our study population was 4.2%. Using M-CHAT as a screener, 8 children failed the M-CHAT, of whom only one was diagnosed with ASD. None of the children that passed the MCHAT was diagnosed with ASD. Only 17 chromosomal study results were available for analysis, 2 children had mosaic DS whereas the remaining was caused by non-disjunction; the only DS-ASD patient had non-disjunction. Regarding parental awareness of dual diagnoses of ASD and DS, about 60% of the parents attending UKMMC clinic were aware of the possibility of ASD-DS diagnosis.

CONCLUSIONS

Our results suggest that ASD prevalence in our DS study population is consistent with those previously reported, and that paediatricians managing DS children should be aware of the dual diagnoses of ASD and DS when managing these patients. Even though, we are unable to make a definitive conclusion regarding the use of M-CHAT in this population of children due to the very small sample size, possibly a multi-centre research in the future may help elucidate this issue.