Prevalence and Age of Onset of Regression in Children with Autism Spectrum Disorder: A Systematic Review and Meta-analytical Update.
Skill loss affects about one in three autistic toddlers, starts near 20 months, and signals need for close follow-up since later outcomes vary widely.
01Research in Context
What this study did
The team pooled 75 studies with 33 the children with autism.
They asked two simple questions: how many kids lose skills, and when does it happen?
Every study had to report clear yes-or-no data on regression and age of onset.
What they found
About 30 out of every 100 autistic children show skill loss.
The average age this loss shows up is 20 months.
But the numbers jump around a lot between studies, so the true rate could be higher or lower.
How this fits with other research
Sharp et al. (2010) already warned that kids who lose skills often end up with more severe symptoms. Christine et al. now tell us how common that loss group is.
Waizbard-Bartov et al. (2022) tracked the same kids past the toddler window and found half change severity again by age 11. The 20-month regression peak is only the first stop on a moving ride.
Solomon et al. (2018) add that IQ paths also split wide after age 2: one-third shoot up 30 points, one-quarter slip back. Taken together, the data say regression at 20 months flags risk but does not lock the child’s future.
Why it matters
When parents report sudden skill loss around the second birthday, take it seriously. Screen for autism right away and plan strong early intervention. Keep measuring—language, play, IQ, adaptive—because change is likely. Use the data to adjust goals and keep families informed that both gains and losses can still happen.
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02At a glance
03Original abstract
A systematic review published in 2013 reported 32% of children on the autism spectrum experience skill loss, known as autistic regression. However, the frequency varied depending on definition and measures used to capture skills. Retrospective parent report and prospective observation indicate loss of language and/or social skills, with motor skills typically unaffected. Our aim was to update the prevalence and age of onset of autistic regression through a meta-analysis of the literature to understand if there have been changes to the reported onset and prevalence since 2010. A systematic literature search was conducted using Medline, Embase, PsycINFO, and the Cochrane Library databases and included studies published from 2010 onward. Risk of bias assessment was performed on included studies. A random effects model was used to calculate the pooled prevalence and age of onset of autistic regression. Ninety-seven studies were included in the systematic review, of which 75 studies involving 33,014 participants had sufficient data for meta-analytic syntheses. The pooled proportion of autistic regression was 30% (95% confidence interval [CI]: 27-32%) but heterogeneity was high (I2 = 96.91) and did not reduce with sensitivity or subgroup analyses based on study design or clinical differences, respectively. Prevalence varied according to risk of bias (low: 27%) and definition of regression (language: 20%, language/social: 40%, mixed: 30%, and unspecified: 27%). Weighted average age of onset was 19.8 months. Findings from this meta-analysis highlight the importance of developing a standardized definition of autistic regression, and tools to measure this at multiple time points during early childhood development. LAY SUMMARY: About a third of children with Autism Spectrum Disorder experience loss of skills, which is also known as autistic regression. This paper provides an update of the rate of autistic regression in children and the age when they first experience loss of skills, based on current studies. The findings from this review contribute to our understanding of the onset patterns of autistic regression. Unfortunately, studies are not sufficiently similar, making it difficult to provide clear answers on the exact timing or type of regression seen in different children.
Autism research : official journal of the International Society for Autism Research, 2021 · doi:10.1002/aur.2463