Down syndrome disintegrative disorder: New-onset autistic regression, dementia, and insomnia in older children and adolescents with Down syndrome

Abstract: Over a 10-year period in a Down syndrome Clinic, 11 children and adolescents were encountered with a history of new-onset (8) or worsening (3) autistic characteristics. Ten of the 11 (91%) had cognitive decline to a dementia-like state and 9 of the 11 (82%) new-onset insomnia. The mean age at which symptoms developed was 11.4 years (standard deviation = 3.6 years; range 5-14 years), an older age than usual for autistic regression in Down syndrome. Ten of 11 cases (91%) had elevated ("positive") thyroperoxidase antibody titers compared to only 5 of 21 (23%) age-matched control subjects with Down syndrome (P < .001). At follow-up at a mean age of 20.7 years (standard deviation = 3.9 years), 8 of the 11 (73%) were at least somewhat better. Down syndrome disintegrative disorder seems an appropriate name for this newly recognized clinical association, which may be due to autoimmunity.
Source: Gordon Worley, Blythe G Crissman, Emily Cadogan, Christie Milleson, Deanna W Adkins, and Priya S Kishnani. Journal of Child Neurology, 2015, Aug, 30(9), 1147-1152. doi: 10.1177/0883073814554654. Epub 2014 Nov 3.