Objectives: To examine the prevalence and types of mannerisms (MAN), unusual sensory interests (USI), and restricted interests/repetitive behaviors (RRB) present in young children who received a diagnosis of ASD by age 24 months (mo) and to assess the relationship between early manifestation of MAN/USI/RRB and stability of ASD diagnosis.
Methods: Retrospective chart review of 74 children presenting by age 24 mo to a University Affiliated early intervention program from 2003 to 2009 who received an ASD diagnosis based on multidisciplinary evaluation and who had follow-up at least 1 year later. Data from initial evaluation included: age, demographics, cognition, DSM-IV criteria, Childhood Autism Rating Scale (CARS) and, in some, the Autism Diagnostic Observation Schedule (ADOS). Characterization of MAN/USI/RRB was based on observations across the multidisciplinary evaluation sessions. ASD diagnosis at follow-up was based on CARS, DSM IV, ADOS, and educational classification. Data of those who retained ASD diagnosis and those who did not were compared. Statistical analysis included chi-square, t-test and nonparametric testing.
Results: Mean age at presentation was 19.9 mo; 68% male; 64% cognitive standard score > 70. At follow-up, mean age was 54.1 mo. 87% of the sample continued to meet criteria for ASD at follow-up. At initial presentation, 87.8% of the sample displayed atypical behaviors.
Frequency of Atypical Behaviors | |||||
Motor Mannerisms (MAN): 55/74 e.g., Hand flapping (24%), Toe walking (19%), Spinning around (26%) |
74%
|
Unusual Sensory Interests (USI): 45/74 e.g., Visual: Eye level play, Squinting, etc. (27%); Other: Licking, Smelling, etc. (34%) |
61%
|
Restricted Interests/ Repetitive Behaviors (RRB): 39/74 e.g., Spinning objects/ wheels (24%), Lining up toys (4%) |
53%
|
The children who continued to meet criteria for ASD at follow-up were more likely to have displayed MAN/USI/RRB at presentation than those who did not (92% vs. 60%, p=0.004). They were especially likely to display motor mannerisms (78% vs. 20%, p<0.001) and to exhibit 2 or more types of MAN/USI/RRB (95% vs. 73%, p=0.006). Those who presented with any MAN/USI/RRB had a significantly higher total CARS score at follow-up (32.8±6.8 vs. 25.7±6.1. p=0.03).
Conclusions: Atypical behaviors were commonly seen in children presenting early with social communicative deficits given an ASD diagnosis. The vast majority of this cohort retained ASD diagnosis at follow-up. The presence of atypical interests and behaviors was predictive of stability of the early diagnosis.
See more of: Clinical Phenotype
See more of: Symptoms, Diagnosis & Phenotype