Summary: Researchers have developed a new algorithm that uses data based on metabolites in blood samples to successfully predict if a child is on the autism spectrum.
Source: Rensselaer Polytechnic Institute.
One year after researchers published their work on a physiological test for autism, a follow-up study confirms its exceptional success in assessing whether a child is on the autism spectrum. A physiological test that supports a clinician’s diagnostic process has the potential to lower the age at which children are diagnosed, leading to earlier treatment. Results of the study, which uses an algorithm to predict if a child has autism spectrum disorder (ASD) based on metabolites in a blood sample, published online today, appear in the June edition of Bioengineering & Translational Medicine.
“We looked at groups of children with ASD independent from our previous study and had similar success. We are able to predict with 88 percent accuracy whether children have autism,” said Juergen Hahn, lead author, systems biologist, professor, head of the Rensselaer Polytechnic Institute Department of Biomedical Engineering, and member of the Rensselaer Center for Biotechnology and Interdisciplinary Studies (CBIS). “This is extremely promising.”
It is estimated that approximately 1.7 percent of all children are diagnosed with ASD, characterized as “a developmental disability caused by differences in the brain,” according to the Centers for Disease Control and Prevention. Earlier diagnosis is generally acknowledged to lead to better outcomes as children engage in early intervention services, and an ASD diagnosis is possible at 18-24 months of age. However, because diagnosis depends solely on clinical observations, most children are not diagnosed with ASD until after 4 years of age.
Rather than search for a sole indicator of ASD, the approach Hahn developed uses big data techniques to search for patterns in metabolites relevant to two connected cellular pathways (a series of interactions between molecules that control cell function) with suspected links to ASD.
“Juergen’s work in developing a physiological test for autism is an example of how the interdisciplinary life science-engineering interface at Rensselaer brings new perspectives and solutions to improve human health,” said Deepak Vashishth, CBIS director. “This is a great result from the larger emphasis on Alzheimer’s and neurodegenerative diseases at CBIS, where our work joins multiple approaches to develop better diagnostic tools and biomanufacture new therapeutics.”
The initial success in 2017 analyzed data from a group of 149 people, about half of whom had been previously diagnosed with ASD. For each member of the group, Hahn obtained data on 24 metabolites related to the two cellular pathways–the methionine cycle and the transsulfuration pathway. Deliberately omitting data from one individual in the group, Hahn subjected the remaining dataset to advanced analysis techniques and used results to generate a predictive algorithm. The algorithm then made a prediction about the data from the omitted individual. Hahn cross-validated the results, swapping a different individual out of the group and repeating the process for all 149 participants. His method correctly identified 96.1 percent of all typically developing participants and 97.6 percent of the ASD cohort.
The results were impressive and created, said Hahn, a new goal: “Can we replicate this?”
The new study applies Hahn’s approach to an independent dataset. To avoid the lengthy process of gathering new data through clinical trials, Hahn and his team searched for existing datasets that included the metabolites he had analyzed in the original study. The researchers identified appropriate data from three different studies that included a total of 154 children with autism conducted by researchers at the Arkansas Children’s Research Institute. The data included only 22 of the 24 metabolites he used to create the original predictive algorithm, however Hahn determined the available information would be sufficient for the test.
The team used their approach to recreate the predictive algorithm, this time using data of the 22 metabolites from the original group of 149 children. The algorithm was then applied to the new group of 154 children for testing purposes. When the predictive algorithm was applied to each individual, it correctly predicted autism with 88 percent accuracy.
Hahn said the difference between the original accuracy rate and that of the new study can likely be attributed to several factors, the most important being that two of the metabolites were unavailable in the second dataset. Each of the two metabolites had been strong indicators in the previous study.
Overall, the second study validates the original results, and provides insights into several variants on the approach.
“The most meaningful result is the high degree of accuracy we are able to obtain using this approach on data collected years apart from the original dataset,” said Hahn. “This is an approach that we would like to see move forward into clinical trials and ultimately into a commercially available test.”
Hahn was joined on the research by Rensselaer doctoral students Troy Vargason and Daniel P. Howsmon; Robert A. Rubin of Whittier College; Leanna Delhey, Marie Tippett, Shannon Rose, and Sirish C. Bennuri of the Arkansas Children’s Research Institute and the University of Arkansas for Medical Sciences; John C. Slattery, Stepan Melnyk, and S. Jill James of the University of Arkansas for Medical Sciences; and Richard E. Frye of Phoenix Children’s Hospital.
Funding: The research was partially funded by the National Institutes of Health.
Source: Mary Martialay – Rensselaer Polytechnic Institute
Publisher: Organized by NeuroscienceNews.com.
Image Source: NeuroscienceNews.com image is credited to Rensselaer.
Original Research: Open access research for “Multivariate techniques enable a biochemical classification of children with autism spectrum disorder versus typically‐developing peers: A comparison and validation study” by Daniel P. Howsmon, Troy Vargason, Robert A. Rubin, Leanna Delhey, Marie Tippett, Shannon Rose, Sirish C. Bennuri, John C. Slattery, Stepan Melnyk, S. Jill James, Richard E. Frye, and Juergen Hahn in Bioengineering & Translational Medicine. Published May 14 2018
[cbtabs][cbtab title=”MLA”]Rensselaer Polytechnic Institute “Success of Blood Test for Autism Affirmed.” NeuroscienceNews. NeuroscienceNews, 19 June 2018.
<https://neurosciencenews.com/autism-blood-test-9379/>.[/cbtab][cbtab title=”APA”]Rensselaer Polytechnic Institute (2018, June 19). Success of Blood Test for Autism Affirmed. NeuroscienceNews. Retrieved June 19, 2018 from https://neurosciencenews.com/autism-blood-test-9379/[/cbtab][cbtab title=”Chicago”]Rensselaer Polytechnic Institute “Success of Blood Test for Autism Affirmed.” https://neurosciencenews.com/autism-blood-test-9379/ (accessed June 19, 2018).[/cbtab][/cbtabs]
Multivariate techniques enable a biochemical classification of children with autism spectrum disorder versus typically‐developing peers: A comparison and validation study
Autism spectrum disorder (ASD) is a developmental disorder which is currently only diagnosed through behavioral testing. Impaired folate‐dependent one carbon metabolism (FOCM) and transsulfuration (TS) pathways have been implicated in ASD, and recently a study involving multivariate analysis based upon Fisher Discriminant Analysis returned very promising results for predicting an ASD diagnosis. This article takes another step toward the goal of developing a biochemical diagnostic for ASD by comparing five classification algorithms on existing data of FOCM/TS metabolites, and also validating the classification results with new data from an ASD cohort. The comparison results indicate a high sensitivity and specificity for the original data set and up to a 88% correct classification of the ASD cohort at an expected 5% misclassification rate for typically‐developing controls. These results form the foundation for the development of a biochemical test for ASD which promises to aid diagnosis of ASD and provide biochemical understanding of the disease, applicable to at least a subset of the ASD population.