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Unexplained regression in Down syndrome: 35 cases from an international Down syndrome database
Santoro SL, Cannon S, Capone G, Franklin C, Hart SJ, Hobensack V, Kishnani PS, Macklin EA et al.. Genetics in medicine : official journal of the American College of Medical Genetics, 2019-11-26
Topic: Brain proteins, microglia and lab models
Purpose An entity of regression in Down syndrome (DS) exists that affects adolescents and young adults and differs from autism spectrum disorder and Alzheimer disease. Methods Since 2017, an international consortium of DS clinics assembled a database of patients with unexplained regression and age- and sex-matched controls. Standardized data on clinical symptoms and tiered medical evaluations were collected. Elements of the proposed definition of unexplained regression in DS were analyzed by paired comparisons between regression cases and matched controls. Results We identified 35 patients with DS and unexplained regression, with a mean age at regression of 17.5 years. Diagnostic features differed substantially between regression cases and matched controls (p Conclusions Our case-control evidence supports a proposed definition of unexplained regression in Down syndrome. Establishing this clinical definition supports future research and investigation of an underlying mechanism.
Key findings
- Results We identified 35 patients with DS and unexplained regression, with a mean age at regression of 17.5 years.
Why it matters
This case-control study described 35 people with Down syndrome who had unexplained regression at an average age of 17.5 years, distinct from Alzheimer disease. It supports a clinical definition to guide future research and does not test treatment or cure.
Study details
- Study designcase-control study
- Participants35
- Evidence strengthModerate
How this study scored 55/100
Published in a peer-reviewed journal, and it is a case-control study. Scored zero for effect reported and randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (Genetics in medicine : official journal of the American College of Medical Genetics) |
| Journal's citation record | 2 / 4 | Genetics in Medicine: journal h-index 204 (OpenAlex, 2026-10-29) |
| Study design | 6 / 12 | A case-control study |
| Strength of evidence | 3 / 5 | Rated “moderate” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 2 / 5 | 2020 — within 10 year(s) of the newest study here |
| Sample size | 1 / 4 | 35 participants |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 3 / 3 | Studied in people (participant count stated) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | 4 / 7 | Cited 61 times (OpenAlex, 2026-10-10) |
| Citations per year | 2 / 5 | 7.6 citations a year over 8 year(s) since 2020 |
| Impact for its field and year | 3 / 6 | Cited 5.9× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 0 / 6 | No other study in this library cites it |
| Still being cited | 2 / 4 | Cited 21 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 2 / 4 | Last-listed author Brian G. Skotko: h-index 40 (OpenAlex, whole career) |
| Institution's track record | 3 / 3 | Harvard University: institution h-index 3,235 (OpenAlex) |
| Multi-centre collaboration | 3 / 3 | OpenAlex lists 10 institution(s) in 3 countries |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 31767984) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 55 / 100 | — |
What each of these 20 components measures, and what this score is not →
Read the original
- DOI: 10.1038/s41436-019-0706-8
- PubMed: 31767984
- Original source →
- Free full text: Genetics in Medicine →
Full text: free to read — OpenAlex lists this copy as free to read: the link above (checked 6 Feb 1020).
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. The record's author list ends in “et al.”, so not every author is named. Check the citation against the original before you use it.
APA 7th
Santoro, S. L., Cannon, S., Capone, G., Franklin, C., Hart, S. J., Hobensack, V., et al. (2020). Unexplained regression in Down syndrome: 35 cases from an international Down syndrome database. Genetics in medicine : official journal of the American College of Medical Genetics. https://doi.org/10.1038/s41436-019-0706-8
Vancouver
Santoro SL, Cannon S, Capone G, Franklin C, Hart SJ, Hobensack V, et al. Unexplained regression in Down syndrome: 35 cases from an international Down syndrome database. Genetics in medicine : official journal of the American College of Medical Genetics. 2020. doi:10.1038/s41436-019-0706-8. PMID: 31767984.
BibTeX
@article{santoro2020-31767984,
author = {Santoro, S. L. and Cannon, S. and Capone, G. and Franklin, C. and Hart, S. J. and Hobensack, V. and Kishnani, P. S. and Macklin, E. A. and others},
title = {{Unexplained regression in Down syndrome: 35 cases from an international Down syndrome database}},
journal = {Genetics in medicine : official journal of the American College of Medical Genetics},
year = {2020},
doi = {10.1038/s41436-019-0706-8},
pmid = {31767984},
url = {https://doi.org/10.1038/s41436-019-0706-8}
}
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