|Credit: Disability Scoop 23 August 2018|
CDC refers to the US Centers for Disease Control and Prevention, and the report is pertinent to their continuing efforts to chart the estimated prevalence of autism in the United States (see here and see here for some examples). This is done to a large extent via the Autism and Developmental Disabilities Monitoring Network (ADDM), with statistics based on the number of eight year olds estimated to be diagnosed with autism or an autism spectrum disorder (ASD). Why 8 year olds? Well, I assume it's because this is an age where autism will (*should*) be diagnosed and avoids any earlier years diagnostic confusion and the like.
But it appears that this initiative does not want to just remain focused on 8 year olds as we are told that: "the agency wants researchers at up to two sites to look at 16-year-olds who were previously identified as having autism symptoms in the network’s tracking when they were age 8." Further: "This goal is basically to find out what’s happened to these kids since age 8."
The rationale behind such a decision is a noble one. It's about looking at whether children diagnosed with autism/ASD "have other health conditions and what types of services they are receiving at school and otherwise." 'Other health conditions'? Erm, I'd hazard a guess and say yes, yes they will typically have some other health conditions (see here) also presenting. It's an agenda that also fits in well with the partial shift in focus from children on the autism spectrum towards teens and adults with autism. As for the 'services they are receiving at school' angle, well, this could also be important in terms of best practice too. I say that mindful of the fact that over here on the other side of the Pond, there has been some significant legal movement on schooling in the context of autism recently (see here).
But there is another aspect to such a decision by the CDC that might also be interesting to look at: that pertinent to the stability of an autism diagnosis (see here and see here for examples).
I know some people don't like to talk about the observation that autism, for some, is not necessarily a lifelong diagnosis (see here). The idea that within the huge heterogeneity included under the label of autism not everyone has a stable presentation across the lifespan is a jarring concept, particularly in the context that some people see their autism as so much more than just a diagnostic label. I hear words like 'masking' and 'camouflaging' being used more often to potentially explain why some people don't meet the diagnostic cut-offs for autism/ASD having previously done so. This may well apply to some people, but I don't think this represents an intellectually satisfying universal explanation for such a phenomenon and denigrates a potentially important finding. That also, 'losing a diagnosis' might impact on other issues 'over-represented' in relation to autism (see here and see here) provides further evidence for something other than masking potentially going on (unless the act of masking is somehow 'protective against' the likelihood of psychiatric comorbidity occurring alongside autism?)
I don't want to pre-empt any decisions from the CDC about their shift in focus and what they will and won't look at. Guaranteed that if such a proposal comes to being, the data will reveal something interesting and important, moving forward from just the autism 'numbers game'. If however, diagnostic stability does crop up as part-and-parcel of the new CDC autism prevalence agenda, I daresay that more research resources will be put into looking at the hows-and-whys of this issue. And perhaps too important areas like whether there are genetic and/or biological 'changes' associated with not subsequent fulfilling the diagnostic criteria for autism will also start to figure.
To close, I'm going to link again to the recent-ish findings from Bal and colleagues  suggesting that "some older adolescents and adults with ASD may not exhibit the same difficulties observed in young children with ASD" as a template for further study in this area. This, as part of a recognition, that "some will be largely free from symptoms of the disorder by adulthood"  (see here for my take) observed by some authors. Feathers will no doubt be ruffled.
 Bal VH. et al. Autism spectrum disorder symptoms from ages 2 to 19 years: Implications for diagnosing adolescents and young adults. Autism Res. 2018 Aug 12.
 Lord C. et al. Autism spectrum disorder. Lancet. 2018 Aug 11;392(10146):508-520.