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INTRODUCTION: The risk reduction for Alzheimer's disease (rrAD) trial was a multisite clinical trial to assess exercise and intensive vascular pharmacological treatment on cognitive function in community‐dwelling older adults at increased risk for Alzheimer's disease. METHODS: Eligibility, consent, and randomization rates across different referral sources were compared. Informal interviews conducted with each site's project team were conducted upon study completion. RESULTS: Initially, 3290 individuals were screened, of whom 28% were eligible to consent, 805 consented to participate (87.2% of those eligible), and 513 (36.3% of those consented) were randomized. Emails sent from study site listservs/databases yielded the highest amount (20.9%) of screened individuals. Professional referrals from physicians yielded the greatest percentage of consented individuals (57.1%). Referrals from non‐professional contacts (ie, friends, family; 75%) and mail/phone contact from a site (73.8%) had the highest yield of randomization. DISCUSSION: Professional referrals or email from listservs/registries were most effective for enrolling participants. The greatest yield of eligible/randomized participants came from non‐professional and mail/phone contacts. Future trials should consider special efforts targeting these recruitment approaches. Highlights: Clinical trial recruitment is commonly cited as a significant barrier to advancing our understanding of cognitive health interventions.The most cited referral source was email, followed by interviews/editorials on the radio, television, local newspapers, newsletters, or magazine articles.The referral method that brought in the largest number of contacts was email but did not result in the greatest yield of consents or eligible participants.The sources that yielded the greatest likelihood of consent were professional referrals (ie, physician), social media, and mail/phone contact from study site.The greatest yield of eligible/randomized participants came from non‐professional contacts and mail/phone contact from a site.Findings suggest that sites may need to focus on more selective referral sources, such as using contact mailing and phone lists, rather than more widely viewed recruitment sources, such as social media or TV/radio advertisements. [ABSTRACT FROM AUTHOR]

Objective. Neuropsychological measures of processing speed have long been used as sensitive indices of cognitive functioning. Most of these commonly used tests are proprietary, and there is a need for brief, freely available tools that can be used in diverse clinical and research settings. The Southwestern Assessment of Processing Speed (SWAPS) is a 60-second digit-symbol transcription task developed as a brief alternative to commercially available coding tests. Demographically-corrected normative data are presented along with reliability and sensitivity/specificity values in older adults with and without cognitive impairment. Method. SWAPS data from 915 healthy aging individuals (NC) and 858 subjects with clinical diagnoses of mild cognitive impairment (MCI; n = 430) and Alzheimer's disease clinical syndrome (ADCS; n = 428) were obtained from the Texas Alzheimer's Research and Care Consortium (TARCC). TARCC participants represent ethnically and educationally diverse community-dwelling individuals age 50+. Results. SWAPS scores showed the expected associations with age, sex, and education, and the interaction between age and education were significant predictors of SWAPS scores. Test-retest reliability in NC was good, and the SWAPS distinguished impaired and non-impaired groups with adequate to excellent sensitivity and specificity for the primary analyses, with optimal cut-off points provided. Raw score- to uncorrected normalized T-scores and demographically-corrected SWAPS T-scores using regression-based norms are presented along with scoring programs for the calculation of each. Conclusions. The SWAPS is a brief, free, easily administered test with demographically-corrected regression-based norms and promising utility for detection of cognitive impairment and efficient assessment of processing speed. [ABSTRACT FROM AUTHOR]

Background: Life expectancy (LE) following Alzheimer's disease (AD) is highly variable. The literature to date is limited by smaller sample sizes and clinical diagnoses.Objective: No study to date has evaluated predictors of AD LE in a retrospective large autopsy-confirmed sample, which was the primary objective of this study.Methods: Participants (≥50 years old) clinically and neuropathologically diagnosed with AD were evaluated using National Alzheimer's Coordinating Center (N = 1,401) data. Analyses focused on 21 demographic, medical, neuropsychiatric, neurological, functional, and global cognitive predictors of LE at AD dementia diagnosis. These 21 predictors were evaluated in univariate analyses. Variables found to be significant were then entered into a forward multiple regression. LE was defined as months between AD diagnosis and death.Results: Fourteen predictors were significant in univariate analyses and entered into the regression. Seven predictors explained 27% of LE variance in 764 total participants. Mini-Mental State Examination (MMSE) score was the strongest predictor of LE, followed by sex, age, race/ethnicity, neuropsychiatric symptoms, abnormal neurological exam results, and functional impairment ratings. Post-hoc analyses revealed correlations of LE were strongest with MMSE ≤12.Conclusion: Global cognitive functioning was the strongest predictor of LE following diagnosis, and AD patients with severe impairment had the shortest LE. AD patients who are older, male, white, and have more motor symptoms, functional impairment, and neuropsychiatric symptoms were also more likely have shorter LE. While this model cannot provide individual prognoses, additional studies may focus on these variables to enhance predictions of LE in patients with AD. [ABSTRACT FROM AUTHOR]

Background: Little is known about the prevalence of polypharmacy, the taking of five or more medications a day, in older adults with specific dementia risk factors.Objective: To examine the prevalence of polypharmacy in participants at baseline in a vascular risk reduction focused Alzheimer's disease (rrAD) trial targeting older patients with hypertension and elevated dementia risk.Methods: We conducted a detailed review of medications in a cross-sectional study of community-dwelling older adults with hypertension and elevated dementia risk. Medications were identified in a structured interview process with an onsite pharmacist or qualified designee. Polypharmacy was defined as use of five or more medications on a regular basis. Descriptive analyses were conducted on the sample as well as direct comparisons of subgroups of individuals with hypertension, diabetes, and hyperlipidemia.Results: The 514 rrAD participants, mean age 68.8 (standard deviation [sd] 6), reported taking different combinations of 472 unique medications at their baseline visit. The median number of medications taken by participants was eight [Range 0-21], with 79.2% exhibiting polypharmacy (n = 407). Sites differed in their prevalence of polypharmacy, χ2(3) = 56.0, p < 0.001. A nearly identical percentage of the 2,077 prescribed (51.8%) and over the counter (48.2%) medications were present in the overall medication profile. The presence of diabetes (87.5%), hyperlipidemia (88.2%), or both (97.7%) was associated with a higher prevalence of polypharmacy than participants who exhibited hypertension in the absence of either of these conditions (63.2%), χ2(3) = 35.8, p < 0.001.Conclusion: Participants in a dementia risk study had high levels of polypharmacy, with the co-existence of diabetes or hyperlipidemia associated with a greater prevalence of polypharmacy as compared to having hypertension alone. [ABSTRACT FROM AUTHOR]

Objective: Medical history information regarding prior traumatic brain injury (TBI) usually relies on self-report, although little is known about the reliability of this information with regard to injuries sustained years or decades earlier. Even less is known about the reliability of self-reported medical history information in older individuals with cognitive impairment. To this end, we assessed the test-retest reliability of self-reported TBI history in a large, national sample. Methods: Participants (n = 4309) were older adults with intact cognition, mild cognitive impairment (MCI) and Alzheimer's disease (AD) from the National Alzheimer's Coordinating Center. Subjects provided TBI history information at baseline and one annual followup visit. Consistency of self-reported history of TBI with <5 minutes loss of consciousness (mLOC) and TBI with =5 mLOC reported at time 1 and 2 was analyzed across diagnostic groups. Results: Overall, subjects provided reports of TBI history at follow-up that were highly consistent with baseline reports (97.8-99.6% agreement), and Cohen's kappa coefficients were all larger than .80 and statistically significant, maximum p < .001. Furthermore, level of cognitive impairment was not a significant predictor of consistency in reporting. Conclusions: These data are some of the first to suggest that self-report may be a consistent method of obtaining remote TBI history in the absence of medical records for older individuals, regardless of cognitive impairment. [ABSTRACT FROM AUTHOR]

[Journal of Alzheimer's Disease, 86 (2022) 271-281, DOI 10.3233/JAD-215200] https://content.iospress.com/articles/journal-of-alzheimers-disease/jad215200 On page 275, there is an error in paragraph 2, section "Additional MMSE I post-hoc i analyses", line 9. In the original, it reads: I "Tukey's post-hoc test revealed significant differences (ps<0.001) in LE between mild (M = 35.8, SD = 26.6), moderate (M = 54.53, SD = 27.23), and severe (M = 67.14, SD = 27.49) cognitive impairment." i The correct line is: I "Tukey's post-hoc test revealed significant differences (p's<0.001) in LE between severe (M = 35.8, SD = 26.6), moderate (M = 54.53, SD = 27.23), and mild (M = 67.14,SD = 27.49) cognitive impairment.". [Extracted from the article]

Objective: The Montreal Cognitive Assessment (MoCA) is a cognitive screening instrument growing in popularity, but few studies have conducted psychometric item analyses or attempted to develop abbreviated forms. We sought to derive and validate a short-form MoCA (SF-MoCA) and compare its classification accuracy to the standard MoCA and Mini-Mental State Examination (MMSE) in mild cognitive impairment (MCI), Alzheimer disease (AD), and normal aging.Methods: 408 subjects (MCIn = 169, ADn = 87, and normaln = 152) were randomly divided into derivation and validation samples. Item analysis in the derivation sample identified most sensitive MoCA items. Receiver Operating Characteristic (ROC) analyses were used to develop cut-off scores and evaluate the classification accuracy of the SF-MoCA, standard MoCA, and MMSE. Net Reclassification Improvement (NRI) analyses and comparison of ROC curves were used to compare classification accuracy of the three measures.Results: Serial subtraction (Cramer’sV = .408), delayed recall (Cramer’sV = .702), and orientation items (Cramer’sV = .832) were included in the SF-MoCA based on largest effect sizes in item analyses. Results revealed 72.6% classification accuracy of the SF-MoCA, compared with 71.9% for the standard MoCA and 67.4% for the MMSE. Results of NRI analyses and ROC curve comparisons revealed that classification accuracy of the SF-MoCA was comparable to the standard version and generally superior to the MMSE.Conclusions: Findings suggest the SF-MoCA could be an effective brief tool in detecting cognitive impairment. [ABSTRACT FROM PUBLISHER]

Alzheimer's disease (AD) has been associated with accumulation of amyloid beta (Aβ) peptides in brain, and immunotherapy targeting Aβ provides potential for AD prevention. We have used a DNA Aβ42 trimer construct for immunization of 3xTg-AD mice and found previously significant reduction of amyloid and tau pathology due to the immunotherapy. We show here that DNA Aβ42 immunized 3xTg-AD mice showed better performance in nest building activities and had a higher 24 months survival rate compared to the non-treated AD controls. The analysis of differently expressed genes in brains from 24 months old mice showed significant increases transcript levels between non-immunized AD mice and wild-type controls for genes involved in microglia and astrocyte function, cytokine and inflammatory signaling, apoptosis, the innate and adaptive immune response and are consistent with an inflammatory phenotype in AD. Most of these upregulated genes were downregulated in the DNA Aβ42 immunized 3xTg-AD mice due to the vaccine. Transcript numbers for the immediate early genes, Arc, Bdnf, Homer1, Egr1 and cfos , involved in neuronal and neurotransmission pathways which were much lower in the non-immunized 3xTg-AD mice, were restored to wild-type mouse brain levels in DNA Aβ42 immunized 3xTg-AD mice indicating positive effects of DNA Aβ42 immunotherapy on synapse stability and plasticity. The immune response after immunization is complex, but the multitude of changes after DNA Aβ42 immunization shows that this response moves beyond the amyloid hypothesis and into direction of disease prevention. Image 1 • DNA Aβ42 immunization increases life span in 3xTg-AD mouse model • DNA Aβ42 immunization downregulates transcripts of inflammatory genes in brain of 3xTg-AD mouse model • DNA Aβ42 immunization restores expression of immediate early genes in brain of 3xTg-AD mouse model to wild-type levels • This is a first report showing effects of DNA Aβ42 immunotherapy on reducing the expression of genes upregulated in AD brain. [ABSTRACT FROM AUTHOR]

Abstract Alzheimer's Disease (AD) is an age-related disease with modifiable risk factors such as hypertension, hypercholesterolemia, obesity, and physical inactivity influencing the onset and progression. There is however, no direct evidence that reducing these risk factors prevents or slows AD. The Risk Reduction for Alzheimer's Disease (rrAD) trial is designed to study the independent and combined effects of intensive pharmacological control of blood pressure and cholesterol and exercise training on neurocognitive function. Six hundred and forty cognitively normal older adults age 60 to 85 years with hypertension and increased risk for dementia will be enrolled. Participants are randomized into one of four intervention group for two years: usual care, Intensive Reduction of Vascular Risk factors (IRVR) with blood pressure and cholesterol reduction, exercise training (EX), and IRVR+EX. Neurocognitive function is measured at baseline, 6, 12, 18, and 24 months; brain MRIs are obtained at baseline and 24 months. We hypothesize that both IRVR and EX will improve global cognitive function, while IRVR+EX will provide a greater benefit than either IRVR or EX alone. We also hypothesize that IRVR and EX will slow brain atrophy, improve brain structural and functional connectivity, and improve brain perfusion. Finally, we will explore the mechanisms by which study interventions impact neurocognition and brain. If rrAD interventions are shown to be safe, practical, and successful, our study will have a significant impact on reducing the risks of AD in older adults. NCT Registration: NCT02913664 [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is the most common form of dementia found in the elderly and disease progression is associated with accumulation of Amyloid beta 1–42 (Aβ42) in brain. An immune-mediated approach as a preventive intervention to reduce amyloid plaques without causing brain inflammation is highly desirable for future clinical use. Genetic immunization, in which the immunizing agent is DNA encoding Aβ42, has great potential because the immune response to DNA delivered into the skin is generally non-inflammatory, and thus differs quantitatively and qualitatively from immune responses elicited by peptides, which are inflammatory with production of IFNγ and IL-17 cytokines by activated T cells. DNA immunization has historically been proven difficult to apply to larger mammals. A potential barrier to use DNA immunization in large mammals is the method for delivery of the DNA antigen. We tested jet injection in mice and rabbits and found good antibody production and safe immune responses (no inflammatory cytokines). We found significant reduction of amyloid plaques and Aβ peptides in brains of the DNA Aβ42 immunized 3xTg-AD mouse model. This study was designed to optimize DNA delivery for possible testing of the DNA Aβ42 vaccine for AD prevention in a clinical trial. • DNA Aβ42 immunization via Jet injection into the skin induced high antibody responses in mice and rabbits. • DNA Aβ42 immunization via Jet injection into the skin did not lead to inflammatory cellular responses. • DNA Aβ42 immunization via Jet injection into the skin resulted in amyloid removal from brain in the 3xTg-AD mouse model. • DNA Aβ42 immunization via Jet injection into the skin improved nesting behavior in the 3xTg-AD mouse model. [ABSTRACT FROM AUTHOR]