ApoE gene polymorphism was examined in 100 adults with Down syndrome with and without dementia (Alzheimer's disease) and 346 control subjects. Additionally, a meta analysis of studies (total N=480 subjects) was performed. Results indicated a similar incidence of the gene across groups but subjects with the allele tended to an earlier onset of…

Comparison of cognitive processes in 23 individuals with Down's syndrome (DS) and 23 individuals of comparable mental handicap without Down's syndrome found that older (above 40 years) DS subjects had significantly poorer outcomes. The areas of speech rate, number finding, and expressive attention appeared to show the earliest signs of dementia of…

Institutionalized patients with Down syndrome (N=307) were monitored for 5 to 10 years to determine prevalence of Alzheimer-type dementia. Prevalence increased from 11% between ages 40 and 49 to 77% between 60 and 69. All patients 70 and over had dementia. Mean age of onset of dementia was 56 years. Neuropathological findings were consistent with…

This report describes the status of 70 adults (ages 22 to 60 at the longitudinal study's beginning) with Down syndrome who are being followed for signs of dementia. After 10 years, 12 met all criteria for dementia, 40 met subsets of criteria, and 18 met no criteria. Information is provided on choice and revision of instruments and dementia…

Because dyspraxia (partial loss of the ability to perform purposeful motor acts) is an early symptom of Alzheimer disease, a 62-item dyspraxia scale adapted for adults with Down syndrome (DS) was developed. Use of the measure over 3.5 years with 72 DS individuals (age 40 or older) found statistically significant deterioration that suggested…

Comparison of adults with mental retardation either with or without Down syndrome and under or over 50 years of age found a significantly higher rate of dementia only in Down syndrome subjects over 50. However, the observed incidence based on functional findings was substantially below the presumed 100% prevalence of neuropathological markers of…

Cross-sectional and longitudinal analyses compared age-related changes in adaptive functioning in institutionalized adults with and without Down's syndrome. Cross-sectional analysis showed significant differences related to level of functioning but not to age or etiology. Longitudinal analysis showed a decline in self-help and communication skills…