Adults with Down syndrome and early stage Alzheimer's disease showed decline in their ability to selectively attend to stimuli in a multitrial cancellation task. They also showed variability in their performance over the test trials, whereas healthy participants showed stability. These changes in performance were observed approximately 2 years…

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…

Rates of dementia in adults with mental retardation without Down syndrome were equivalent to or lower than would be expected compared to general population rates, whereas prevalence rates of other chronic health concerns varied as a function of condition. Given that individual differences in vulnerability to Alzheimer's disease have been…

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…

The utility of the Test for Severe Impairment was studied with 60 older persons who had Down Syndrome. Construct validity, test-retest reliability, and interrater reliability were established for the full study group and for subgroups based on degree of mental retardation and dementia status. Some possible applications and limitations of the test…

Emotional factors were studied in 30 adults with Down's syndrome, 18 controls with Alzheimer disease, and 25 elderly controls without mental retardation. Primary emotional factors separating Down's syndrome and Alzheimer disease groups from elderly control subjects without mental retardation were indifference, pragnosia, and inappropriateness.…

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…