Hello, and welcome to the Community Newsletter! I’m your host, Chelsey B. Coombs, Spectrum’s engagement editor.
Before we get into the meat of this week’s newsletter, we want to let you know that we will be covering the International Society for Autism Research conference virtually next week and want to hear your thoughts on it. What sessions are you most excited about? Tweet us @spectrum or email chelsey@spectrumnews.org.
Our first tweet this week comes from Lucy Livingston, lecturer in psychology at Cardiff University in the United Kingdom, about a new paper published in the American Journal of Psychiatry: “Variable emergence of autism spectrum disorder symptoms from childhood to early adulthood.”
New paper led by @anita_thapar1 & Lucy Riglin @MRCcardiff – we find evidence that autistic symptoms can first emerge in adolescence/early adulthood. Does compensation/camouflaging/environmental scaffolding mean symptoms do not fully manifest in childhood?https://t.co/gor3k94gA3
— Lucy Anne Livingston (@Lucy_Livingston) April 27, 2021
The researchers used data from the Avon Longitudinal Study of Parents and Children cohort in the U.K. They analyzed children’s scores at age 7, 10, 13, 17 and 25 on the Social and Communication Disorders Checklist, a parent questionnaire that screens for autism traits.
From these data, the researchers categorized the children by their trait trajectories. Almost 89 percent fell into a ‘low trajectory’ group that showed few autism traits at any point in time. A ‘declining trajectory’ group, which made up 5 percent of the cohort, showed more autism traits during childhood than later on. The remaining 7 percent followed a third, ‘late-emerging trajectory,’ with few autism traits in childhood but an increase throughout adolescence and adulthood.
“[The findings] also challenge our current understanding that ASD symptoms invariably manifest early in development,” the researchers wrote.
People in the late-emerging trajectory group showed more neurodevelopmental challenges in childhood than did those in the low-trajectory group, the team also found. They hypothesize that those children camouflaged their traits, “perhaps as a result of accommodating environments, scaffolding by families, or individual characteristics that enabled them to compensate during this developmental period, but that with increasing demands on social skills with age, social difficulties became more apparent.”
Meng-Chuan Lai, assistant professor of psychiatry at the University of Toronto in Canada, tweeted that the study was “food for thought about what Neurodevelopmental Conditions entail and how they manifest.”
Very interesting and thought provoking findings, & food for thought about what Neurodevelopmental Conditions entail and how they manifest. https://t.co/sELwJ2ZAPG
— Meng-Chuan Lai (@mengchuanlai) April 28, 2021
Hywel Williams, senior lecturer in bioinformatics at Cardiff University, wrote that the study “expand[s] our understanding of when autism symptoms first manifest.”
Tinca Polderman, associate professor of child and adolescent psychiatry at Vrije Universiteit Amsterdam in the Netherlands, wrote that this late-emergence trajectory is also seen in the Netherlands Autism Register.
Very nice piece of research with some interesting results that expand our understanding of when autism symptoms first manifest.
Good work by the team!
— Hywel Williams (@GeneFiddler) April 27, 2021
Our next thread comes from Hilde Geurts, professor of clinical neuropsychology at the University of Amsterdam in the Netherlands, who has a new paper in Clinical Psychology Review called “Validation strategies for subtypes in psychiatry: A systematic review of research on autism spectrum disorder.”
Thread alert! A brand new paper by @JoostAgelinkvR @MarieDeserno & myself which I am rather proud of. Why? Because it can help us, who focus on #heterogeneity and #subgrouping to do better..1/n https://t.co/zYhqBbxkNM
— Hilde Geurts (@dutcharc) April 23, 2021
The team reviewed 156 papers published since 2000 that looked at creating subgroups of autistic people and recommended using the SUbtyping VAlidation Checklist (SUVAC) to validate such results.
In her thread, Geurts highlighted the seven strategies in the SUVAC process.
1. Cross-(statistical) method replication: 2. Subtype separation; 3. Independent replication; 4. Temporal stability; 5. External validation; 6. Parallel replication; 7. Predictive validity. 5/n
— Hilde Geurts (@dutcharc) April 23, 2021
The review found that the majority of the subgrouping papers had been published after 2016 and that 82 percent found two to four subtypes of autism.
“We hoped when starting this endeavour that we could draw conclusions for which subgroups there is clear evidence that they are indeed sufficiently valid & of use for clinical practice…but we couldn’t,” Geurts tweeted.
ps & yes we hoped when starting this endeavour that we could draw conclusions for which subgroups there is clear evidence that they are indeed sufficiently valid & of use for clinical practice…but we couldn’t Disappointing? Yes, so step up your game subgrouping-field! 7/n
— Hilde Geurts (@dutcharc) April 23, 2021
Michelle Dawson, an autism researcher at Hôpital Rivière-des-Prairies in Montreal, Canada, tweeted that it was a “timely, thoughtful, thorough, extremely useful systematic review.”
That’s a timely, thoughtful, thorough, extremely useful systematic review (now open access) of attempts to find autism subtypes. Note: I always learn a lot reading anything from @dutcharc https://t.co/ksLtrZr90F
— Michelle Dawson (@autismcrisis) April 24, 2021
Marita Cooper, a postdoctoral researcher at the Children’s Hospital of Philadelphia in Pennsylvania, tweeted, “Interesting thread on standardizing processes for examining psychiatric subtypes.”
Interesting thread on standardizing processes for examining psychiatric subtypes https://t.co/4kyw5azptt
— MaritaCooperPhD (she/hers) (@MaritaCooperPhD) April 23, 2021
Eiko Fried, associate professor of clinical psychology at Universiteit Leiden in the Netherlands, also wrote a thread about the research, in which he discussed what he views are problems with subtyping research.
Really important work, not only for autism/ASD.
TLDR: a systematic review of subtyping approaches finds that not only methods are all over the place, but validators to groups are often only added after they are derived. Study proposes checklist for psychiatric subtype validation. https://t.co/Oi9nK0g1P1— Eiko Fried (@EikoFried) April 23, 2021
Fried cites a number of issues within the statistical modeling itself, as well as “Problematic reification of subtypes; people often give these subtypes names (e.g. “melancholic” or “atypical” depression), when the empirically derived subtypes have little to do with these theoretical ideas.”
2/ Problematic reification of subtypes; people often give these subtypes names (e.g. “melancholic” or “atypical” depression), when when the empirically derived subtypes have little to do with these theoretical ideas.
Both problems discussed in: https://t.co/BJ2aTI6tlN
— Eiko Fried (@EikoFried) April 23, 2021
Finally, we wanted to highlight a Spectrum opinion article by Jessica Jiménez and Mark Zylka that got a lot of attention this week on social media: “Few autism researchers control for the ‘litter effect’ — this needs to change.”
Because animals within a litter are more similar to one another than animals between litters, researchers will get skewed results if they try to increase their sample size by using many animals from a small number of litters.
“We hope that our article will bring greater awareness to the litter effect and help scientists appropriately design future studies to minimize the impact of litter-to-litter variation in rodent models of autism,” Jiménez and Zylka wrote.
Uri Kahanovitch, a postdoctoral researcher at the University of Western Ontario in Canada, said, “This is an important read, not just autism researchers, but for all who do research on rodents.”
This is an important read, not just autism researchers, but for all who do research on rodents https://t.co/naiCGUgFn8
— Uri Kahanovitch (@UKahanovitch) April 27, 2021
Amy Ryan, a postdoctoral researcher at the University of California, Davis, replied, “Siblings lived in the womb together and will be more similar to each other than others no matter the experimental design, and we need to account for that!”
Great discussion on improving methods and/or data analysis for species that have litters. Siblings lived in the womb together and will be more similar to each other than others no matter the experimental design, and we need to account for that! https://t.co/Uo5nRsF6vY
— Amy Ryan, Ph.D. (@Amy_M_Ryan) April 27, 2021
Will Kenkel, assistant professor of psychological and brain sciences at the University of Delaware in Newark, talked up using voles in research to avoid the litter effect.
This why working with voles is nice: small litters means less opportunities for litter effects to muck up your results. https://t.co/WINYdfuWQq
— Bill Nihilist, Science Guyilist (@wmkenkel) April 27, 2021
That’s it for Spectrum’s Community Newsletter this week. If you have any suggestions about interesting social posts you have seen in the autism research sphere, feel free to send an email to me at chelsey@spectrumnews.org. See you next week!
The post Community Newsletter: Late-emerging autism, validation of subtypes, litter effect appeared first on Spectrum | Autism Research News.
