Nearly all adults with Down syndrome show neuropathology of Alzheimer's disease, including amyloid-β deposition, by their fifth decade of life. In the current study, we examined the association between brain amyloid-β deposition, assessed via in vivo assessments of neocortical Pittsburgh compound B, and scores on an extensive neuropsychological battery of measures of cognitive functioning in 63 adults (31 male, 32 female) with Down syndrome aged 30-53 years who did not exhibit symptoms of dementia. Twenty-two of the adults with Down syndrome were identified as having elevated neocortical Pittsburgh compound B retention levels. There was a significant positive correlation (r = 0.62, P < 0.0001) between age and neocortical Pittsburgh compound B retention. This robust association makes it difficult to discriminate normative age-related decline in cognitive functioning from any potential effects of amyloid-β deposition. When controlling for chronological age in addition to mental age, there were no significant differences between the adults with Down syndrome who had elevated neocortical Pittsburgh compound B retention levels and those who did not on any of the neuropsychological measures. Similarly, when examining Pittsburgh compound B as a continuous variable, after controlling for mental age and chronological age, only the Rivermead Picture Recognition score was significantly negatively associated with neocortical Pittsburgh compound B retention. Our findings indicate that many adults with Down syndrome can tolerate amyloid-β deposition without deleterious effects on cognitive functioning. However, we may have obscured true effects of amyloid-β deposition by controlling for chronological age in our analyses. Moreover, our sample included adults with Down syndrome who were most 'resistant' to the effects of amyloid-β deposition, as adults already exhibiting clinical symptoms of dementia symptoms were excluded from the study.

Introduction In Down syndrome (DS), the overproduction of amyloid precursor protein is hypothesized to predispose young adults to early expression of Alzheimer-like neuropathology. Methods PET imaging with [11C]PiB examined the pattern of amyloid-β deposition in 68 nondemented adults with DS (30-53 years) to determine the relationship between deposition and normal aging. Standard uptake value ratio (SUVR) images were created with cerebellum as the reference region. Results Multiple linear regression revealed slight but highly significant (corrected p<0.05) positive correlations between SUVR and age. The striatum showed the strongest correlation, followed by precuneus, parietal cortex, anterior cingulate, frontal cortex, and temporal cortex. Conclusion There is an age-related amyloid-β deposition in the DS population, but as a pattern of elevated cortical retention becomes apparent, the correlation of SUVR with age ceases to be significant. Factors unrelated to aging may drive an increase in deposition during early Alzheimer's disease pathogenesis.

IntroductionDown syndrome (DS) arises from a triplication of chromosome 21, causing overproduction of the amyloid precursor protein and predisposes individuals to early Alzheimer's disease (AD).MethodsFifty-two nondemented adults with DS underwent two cycles of carbon 11-labeled Pittsburgh compound B ([11C]PiB) and T1 weighted magnetic resonance imaging (MRI) scans 3.0 ± 0.6 years apart. Standard uptake value ratio (SUVR) images (50–70 minutes; cerebellar gray matter [GM]) and GM volumes were analyzed in standardized space (Montreal Neurological Institute space).Results85% of PiB(−) subjects remained PiB(−), whereas 15% converted to PiB(+), predominantly in the striatum. None reverted from PiB(+) to PiB(−). Increases in SUVR were distributed globally, but there were no decreases in GM volume. The PiB positivity groups differed in the percent rate of change in SUVR [PiB(−): 0.5%/year, PiB converters: 4.9%/year, and PiB(+): 3.7%/year], but not in GM volume.DiscussionDespite the characteristic striatum-first pattern, the global rate of amyloid accumulation differs by pre-existing amyloid burden and precedes atrophy or dementia in the DS population, similar to general AD progression.

Adults with Down syndrome (DS) have a high incidence of Alzheimer’s disease (AD), providing a unique opportunity to explore the early, preclinical stages of AD neuropathology. We examined change in brain amyloid-β accumulation via the PET tracer [11C] Pittsburgh compound B (PiB) across two data collection cycles, spaced 3 years apart, and decline in cognitive functioning in 58 adults with DS without clinical AD. PiB retention increased in the anterior cingulate gyrus, precuneus cortex, parietal cortex and anterior ventral striatum. Across the two cycles, 14 (27.5%) participants were consistently PiB+, 31 (60.8%) were consistently PiB−, and 6 (11.7%) converted from PiB− at Cycle 1 to PiB+ at Cycle 2. Increased global amyloid-β was related to decline in verbal episodic memory, visual episodic memory, executive functioning, and fine motor processing speed. Participants who were consistently PiB+ demonstrated worsening of episodic memory, whereas participants who were consistently PiB− evidenced stable or improved performance. Amyloid-β accumulation may be a contributor to or biomarker of declining cognitive functioning in preclinical AD in DS.

Background There is a paucity of research on psychosocial treatments for depression in adults with intellectual disability (ID). In this pilot study, we explored the efficacy of a group CBT treatment that involved a caregiver component in adults with mild ID with a depressive disorder. Method Sixteen adults with mild ID and a depressive disorder participated in a 10-week group CBT treatment and 8 adults with mild ID with a depressive disorder served as a treatment as usual (TAU) control group. Adults with mild ID and caregivers completed measures of depressive symptoms, behavior problems, and social skills at pre-treatment, post-treatment, and a 3-month follow-up. Adults with mild ID also completed a series of tasks to measure their understanding of the principles of cognitive therapy pre- and post-treatment. Results The CBT group demonstrated significant decreases in depressive symptoms and behavior problems from pre-treatment to post-treatment and these effects were maintained at a 3-month follow-up. The CBT group demonstrated significant improvements in their ability to infer emotions and thoughts based on various situation-thought-emotion pairings from pre-treatment to post-treatment. Conclusions Findings indicate that adults with mild ID with a depressive disorder benefitted from a group CBT treatment with a caregiver component. Moreover, adults with mild ID appeared to benefit, at least in part, from the cognitive therapy components of the treatment, in addition to the behavior therapy components.