Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 118
Filter
1.
Alzheimers Dement ; 20(5): 3429-3441, 2024 May.
Article in English | MEDLINE | ID: mdl-38574374

ABSTRACT

INTRODUCTION: To support clinical trial designs focused on early interventions, our study determined reliable early amyloid-ß (Aß) accumulation based on Centiloids (CL) in pre-dementia populations. METHODS: A total of 1032 participants from the Amyloid Imaging to Prevent Alzheimer's Disease-Prognostic and Natural History Study (AMYPAD-PNHS) and Insight46 who underwent [18F]flutemetamol, [18F]florbetaben or [18F]florbetapir amyloid-PET were included. A normative strategy was used to define reliable accumulation by estimating the 95th percentile of longitudinal measurements in sub-populations (NPNHS = 101/750, NInsight46 = 35/382) expected to remain stable over time. The baseline CL threshold that optimally predicts future accumulation was investigated using precision-recall analyses. Accumulation rates were examined using linear mixed-effect models. RESULTS: Reliable accumulation in the PNHS was estimated to occur at >3.0 CL/year. Baseline CL of 16 [12,19] best predicted future Aß-accumulators. Rates of amyloid accumulation were tracer-independent, lower for APOE ε4 non-carriers, and for subjects with higher levels of education. DISCUSSION: Our results support a 12-20 CL window for inclusion into early secondary prevention studies. Reliable accumulation definition warrants further investigations.


Subject(s)
Alzheimer Disease , Amyloid beta-Peptides , Aniline Compounds , Positron-Emission Tomography , Humans , Male , Female , Aged , Amyloid beta-Peptides/metabolism , Alzheimer Disease/diagnostic imaging , Alzheimer Disease/metabolism , Prognosis , Middle Aged , Longitudinal Studies , Stilbenes , Brain/diagnostic imaging , Brain/metabolism , Benzothiazoles
2.
Neurology ; 102(6): e208053, 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38377442

ABSTRACT

OBJECTIVES: Higher-educated patients with Alzheimer disease (AD) can harbor greater neuropathologic burden than those with less education despite similar symptom severity. In this study, we assessed whether this observation is also present in potential preclinical AD stages, namely in individuals with subjective cognitive decline and clinical features increasing AD likelihood (SCD+). METHODS: Amyloid-PET information ([18F]Flutemetamol or [18F]Florbetaben) of individuals with SCD+, mild cognitive impairment (MCI), and AD were retrieved from the AMYPAD-DPMS cohort, a multicenter randomized controlled study. Group classification was based on the recommendations by the SCD-I and NIA-AA working groups. Amyloid PET images were acquired within 8 months after initial screening and processed with AMYPYPE. Amyloid load was based on global Centiloid (CL) values. Educational level was indexed by formal schooling and subsequent higher education in years. Using linear regression analysis, the main effect of education on CL values was tested across the entire cohort, followed by the assessment of an education-by-diagnostic-group interaction (covariates: age, sex, and recruiting memory clinic). To account for influences of non-AD pathology and comorbidities concerning the tested amyloid-education association, we compared white matter hyperintensity (WMH) severity, cardiovascular events, depression, and anxiety history between lower-educated and higher-educated groups within each diagnostic category using the Fisher exact test or χ2 test. Education groups were defined using a median split on education (Md = 13 years) in a subsample of the initial cohort, for whom this information was available. RESULTS: Across the cohort of 212 individuals with SCD+ (M(Age) = 69.17 years, F 42.45%), 258 individuals with MCI (M(Age) = 72.93, F 43.80%), and 195 individuals with dementia (M(Age) = 74.07, F 48.72%), no main effect of education (ß = 0.52, 95% CI -0.30 to 1.58), but a significant education-by-group interaction on CL values, was found (p = 0.024) using linear regression modeling. This interaction was driven by a negative association of education and CL values in the SCD+ group (ß = -0.11, 95% CI -4.85 to -0.21) and a positive association in the MCI group (ß = 0.15, 95% CI 0.79-5.22). No education-dependent differences in terms of WMH severity and comorbidities were found in the subsample (100 cases with SCD+, 97 cases with MCI, 72 cases with dementia). DISCUSSION: Education may represent a factor oppositely modulating subjective awareness in preclinical stages and objective severity of ongoing neuropathologic processes in clinical stages.


Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Aged , Female , Humans , Male , Alzheimer Disease/diagnostic imaging , Alzheimer Disease/epidemiology , Amyloid , Amyloid beta-Peptides , Amyloidogenic Proteins , Biomarkers , Cognitive Dysfunction/diagnostic imaging , Cognitive Dysfunction/epidemiology , Educational Status , Longitudinal Studies , Positron-Emission Tomography , Multicenter Studies as Topic , Randomized Controlled Trials as Topic
3.
Int J Geriatr Psychiatry ; 39(2): e6067, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38323729

ABSTRACT

OBJECTIVES: It is important to determine if cognitive measures identified as being prognostic in dementia research cohorts also have utility in memory clinics. We aimed to identify measures with the greatest power to predict future Alzheimer's disease (AD) dementia in a clinical setting where expensive biomarkers are not widely available. METHODS: This study utilized routine Memory Clinic data collected over 18 years. From 2214 patients assessed in the clinic, we selected 328 patients with an initial diagnosis of subjective cognitive decline or mild cognitive impairment. We compared two types of statistical model for the prediction of AD dementia. The first model included baseline cognitive test scores only, while the second model also included change scores between baseline and the first follow-up. RESULTS: Baseline scores on tests of global cognitive function (Mini-mental state examination and Cambridge Cognitive Examination-Revised), verbal episodic memory and psychomotor speed were the best predictors of conversion to AD dementia. The inclusion of cognitive change scores over 1 year of follow-up improved predictive accuracy versus baseline scores alone. CONCLUSIONS: We found that the best cognitive predictors of AD dementia in a clinical setting were similar to those previously identified using research cohorts. Taking change in cognitive function into account enabled the onset of AD dementia to be predicted with greater accuracy.


Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Humans , Alzheimer Disease/diagnosis , Disease Progression , Cognitive Dysfunction/diagnosis , Prognosis , Biomarkers , Cognition , Neuropsychological Tests
4.
MethodsX ; 12: 102542, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38313693

ABSTRACT

Data-driven solutions offer great promise for improving healthcare. However, standard clinical neuroimaging data is subject to real-world imaging artefacts that can render the data unusable for computational research and quantitative neuroradiology. T1 weighted structural MRI is used in dementia research to obtain volumetric measurements from cortical and subcortical brain regions. However, clinical radiologists often prioritise T2 weighted or FLAIR scans for visual assessment. As such, T1 weighted scans are often acquired but may not be a priority, resulting in artefacts such as partial brain coverage being systematically present in memory clinic data. Here we present "MRI Crop Filling", a pipeline to replace the missing T1 data with synthetic data generated from the T2 scan, making real-world clinical T1 data usable for computational research including the latest AI innovations. Our method consists of the following steps:•Register scans: T2 and (cropped) T1.•Synthesise a new T1 using an open source deep learning tool.•Replace missing (cropped) T1 data in original T1 scan and super-resolve to improve image quality.

5.
BMJ Open ; 14(2): e075273, 2024 02 01.
Article in English | MEDLINE | ID: mdl-38307536

ABSTRACT

INTRODUCTION: Many people living with dementia experience sleep disturbance and there are no known effective treatments. Non-pharmacological treatment options should be the first-line sleep management. For family carers, relatives' sleep disturbance leads to interruption of their sleep, low mood and breakdown of care. Our team developed and delivered DREAMS START (Dementia RElAted Manual for Sleep; STrAtegies for RelaTives), a multimodal non-pharmacological intervention, showing it to be feasible and acceptable. The aim of this randomised controlled trial is to establish whether DREAMS START is clinically cost-effective in reducing sleep disturbances in people living with dementia living at home compared with usual care. METHODS AND ANALYSIS: We will recruit 370 participant dyads (people living with dementia and family carers) from memory services, community mental health teams and the Join Dementia Research Website in England. Those meeting inclusion criteria will be randomised (1:1) either to DREAMS START or to usual treatment. DREAMS START is a six-session (1 hour/session), manualised intervention delivered every 1-2 weeks by supervised, non-clinically trained graduates. Outcomes will be collected at baseline, 4 months and 8 months with the primary outcome being the Sleep Disorders Inventory score at 8 months. Secondary outcomes for the person with dementia (all proxy) include quality of life, daytime sleepiness, neuropsychiatric symptoms and cost-effectiveness. Secondary outcomes for the family carer include quality of life, sleep disturbance, mood, burden and service use and caring/work activity. Analyses will be intention-to-treat and we will conduct a process evaluation. ETHICS AND DISSEMINATION: London-Camden & Kings Cross Ethics Committee (20/LO/0894) approved the study. We will disseminate our findings in high-impact peer-reviewed journals and at national and international conferences. This research has the potential to improve sleep and quality of life for people living with dementia and their carers, in a feasible and scalable intervention. TRIAL REGISTRATION NUMBER: ISRCTN13072268.


Subject(s)
Caregivers , Dementia , Humans , Cost-Benefit Analysis , Caregivers/psychology , Quality of Life , Dementia/complications , Dementia/therapy , Sleep , Randomized Controlled Trials as Topic , Multicenter Studies as Topic
6.
Alzheimers Dement ; 20(3): 1815-1826, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38131463

ABSTRACT

INTRODUCTION: Sex influences neurodegeneration, but it has been poorly investigated in dementia with Lewy bodies (DLB). We investigated sex differences in brain atrophy in DLB using magnetic resonance imaging (MRI). METHODS: We included 436 patients from the European-DLB consortium and the Mayo Clinic. Sex differences and sex-by-age interactions were assessed through visual atrophy rating scales (n = 327; 73 ± 8 years, 62% males) and automated estimations of regional gray matter volume and cortical thickness (n = 165; 69 ± 9 years, 72% males). RESULTS: We found a higher likelihood of frontal atrophy and smaller volumes in six cortical regions in males and thinner olfactory cortices in females. There were significant sex-by-age interactions in volume (six regions) and cortical thickness (seven regions) across the entire cortex. DISCUSSION: We demonstrate that males have more widespread cortical atrophy at younger ages, but differences tend to disappear with increasing age, with males and females converging around the age of 75. HIGHLIGHTS: Male DLB patients had higher odds for frontal atrophy on radiological visual rating scales. Male DLB patients displayed a widespread pattern of cortical gray matter alterations on automated methods. Sex differences in gray matter measures in DLB tended to disappear with increasing age.


Subject(s)
Alzheimer Disease , Lewy Body Disease , Humans , Male , Female , Lewy Body Disease/diagnostic imaging , Lewy Body Disease/pathology , Alzheimer Disease/pathology , Sex Characteristics , Cerebral Cortex/pathology , Atrophy/pathology , Magnetic Resonance Imaging
8.
JAMA Neurol ; 80(6): 548-557, 2023 06 01.
Article in English | MEDLINE | ID: mdl-37155177

ABSTRACT

Importance: Amyloid positron emission tomography (PET) allows the direct assessment of amyloid deposition, one of the main hallmarks of Alzheimer disease. However, this technique is currently not widely reimbursed because of the lack of appropriately designed studies demonstrating its clinical effect. Objective: To assess the clinical effect of amyloid PET in memory clinic patients. Design, Setting, and Participants: The AMYPAD-DPMS is a prospective randomized clinical trial in 8 European memory clinics. Participants were allocated (using a minimization method) to 3 study groups based on the performance of amyloid PET: arm 1, early in the diagnostic workup (within 1 month); arm 2, late in the diagnostic workup (after a mean [SD] 8 [2] months); or arm 3, if and when the managing physician chose. Participants were patients with subjective cognitive decline plus (SCD+; SCD plus clinical features increasing the likelihood of preclinical Alzheimer disease), mild cognitive impairment (MCI), or dementia; they were assessed at baseline and after 3 months. Recruitment took place between April 16, 2018, and October 30, 2020. Data analysis was performed from July 2022 to January 2023. Intervention: Amyloid PET. Main Outcome and Measure: The main outcome was the difference between arm 1 and arm 2 in the proportion of participants receiving an etiological diagnosis with a very high confidence (ie, ≥90% on a 50%-100% visual numeric scale) after 3 months. Results: A total of 844 participants were screened, and 840 were enrolled (291 in arm 1, 271 in arm 2, 278 in arm 3). Baseline and 3-month visit data were available for 272 participants in arm 1 and 260 in arm 2 (median [IQR] age: 71 [65-77] and 71 [65-77] years; 150/272 male [55%] and 135/260 male [52%]; 122/272 female [45%] and 125/260 female [48%]; median [IQR] education: 12 [10-15] and 13 [10-16] years, respectively). After 3 months, 109 of 272 participants (40%) in arm 1 had a diagnosis with very high confidence vs 30 of 260 (11%) in arm 2 (P < .001). This was consistent across cognitive stages (SCD+: 25/84 [30%] vs 5/78 [6%]; P < .001; MCI: 45/108 [42%] vs 9/102 [9%]; P < .001; dementia: 39/80 [49%] vs 16/80 [20%]; P < .001). Conclusion and Relevance: In this study, early amyloid PET allowed memory clinic patients to receive an etiological diagnosis with very high confidence after only 3 months compared with patients who had not undergone amyloid PET. These findings support the implementation of amyloid PET early in the diagnostic workup of memory clinic patients. Trial Registration: EudraCT Number: 2017-002527-21.


Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Humans , Male , Female , Aged , Alzheimer Disease/psychology , Brain/metabolism , Prospective Studies , Positron-Emission Tomography , Amyloid/metabolism , Amyloidogenic Proteins , Amyloid beta-Peptides/metabolism
9.
Res Sq ; 2023 Jan 27.
Article in English | MEDLINE | ID: mdl-36747755

ABSTRACT

Background and objectives: Sex is an important contributing factor to neuroimaging phenotypes in brain disorders. However, little is known about the contribution of sex differences to the neurodegeneration in dementia with Lewy bodies (DLB). We investigated sex differences in probable DLB patients by using both visual rating scales of lobar atrophy and automated estimations of regional atrophy. Methods: We included 442 probable DLB patients from the European-DLB consortium and the Mayo Clinic who have magnetic resonance imaging (MRI) data available. We assessed sex differences and the sex-by-age interaction in two largely independent samples through visual rating scales of lobar atrophy (n = 333; mean age 73 ± 8 years, 62% males) and automated regional estimations of gray matter (GM) volume and mean cortical thickness (CTh) (n = 165; mean age 69 ± 9 years, 72% males). We used binary logistic regression and ANOVA for statistical analysis. Results: We found a statistically significantly higher likelihood of frontal atrophy measured by the global cortical atrophy-frontal subscale (GCA-F) in males (40% of males had an abnormal GCA-F score versus 29% of females, P-value = 0.006). Using automated estimations, we found smaller GM volumes in 6 cortical regions in males compared with females, as well as smaller GM volume in the entorhinal cortex and thinner olfactory cortices in females, compared with males. The sex-by-age interaction showed statistically significant results in 6 cortical volumes and 7 mean CTh estimations (P-value ≤ 0.05), accentuated in the right middle frontal gyrus (FDR-adjusted P-value = 0.047). These cross-sectional interactions indicated that while females have statistically significantly less atrophy than males at younger ages, differences become non-significant at older ages, with females showing the same level of atrophy than males around the age of 75. Conclusions: This study demonstrates sex differences on brain atrophy in probable DLB. While male DLB patients have a more widespread pattern of cortical atrophy at younger ages, these sex differences tend to disappear with increasing age. Longitudinal studies will help establish these cross-sectional findings and inform on sex and age considerations to the use of MRI in clinical routine, as the field moves towards precision medicine.

10.
JAMA Netw Open ; 6(1): e2250921, 2023 01 03.
Article in English | MEDLINE | ID: mdl-36637820

ABSTRACT

Importance: Individuals who are amyloid-positive with subjective cognitive decline and clinical features increasing the likelihood of preclinical Alzheimer disease (SCD+) are at higher risk of developing dementia. Some individuals with SCD+ undergo amyloid-positron emission tomography (PET) as part of research studies and frequently wish to know their amyloid status; however, the disclosure of a positive amyloid-PET result might have psychological risks. Objective: To assess the psychological outcomes of the amyloid-PET result disclosure in individuals with SCD+ and explore which variables are associated with a safer disclosure in individuals who are amyloid positive. Design, Setting, and Participants: This prospective, multicenter study was conducted as part of The Amyloid Imaging to Prevent Alzheimer Disease Diagnostic and Patient Management Study (AMYPAD-DPMS) (recruitment period: from April 2018 to October 2020). The setting was 5 European memory clinics, and participants included patients with SCD+ who underwent amyloid-PET. Statistical analysis was performed from July to October 2022. Exposures: Disclosure of amyloid-PET result. Main Outcomes and Measures: Psychological outcomes were defined as (1) disclosure related distress, assessed using the Impact of Event Scale-Revised (IES-R; scores of at least 33 indicate probable presence of posttraumatic stress disorder [PTSD]); and (2) anxiety and depression, assessed using the Hospital Anxiety and Depression scale (HADS; scores of at least 15 indicate probable presence of severe mood disorder symptoms). Results: After disclosure, 27 patients with amyloid-positive SCD+ (median [IQR] age, 70 [66-74] years; gender: 14 men [52%]; median [IQR] education: 15 [13 to 17] years, median [IQR] Mini-Mental State Examination [MMSE] score, 29 [28 to 30]) had higher median (IQR) IES-R total score (10 [2 to 14] vs 0 [0 to 2]; P < .001), IES-R avoidance (0.00 [0.00 to 0.69] vs 0.00 [0.00 to 0.00]; P < .001), IES-R intrusions (0.50 [0.13 to 0.75] vs 0.00 [0.00 to 0.25]; P < .001), and IES-R hyperarousal (0.33 [0.00 to 0.67] vs 0.00 [0.00 to 0.00]; P < .001) scores than the 78 patients who were amyloid-negative (median [IQR], age, 67 [64 to 74] years, 45 men [58%], median [IQR] education: 15 [12 to 17] years, median [IQR] MMSE score: 29 [28 to 30]). There were no observed differences between amyloid-positive and amyloid-negative patients in the median (IQR) HADS Anxiety (-1.0 [-3.0 to 1.8] vs -2.0 [-4.8 to 1.0]; P = .06) and Depression (-1.0 [-2.0 to 0.0] vs -1.0 [-3.0 to 0.0]; P = .46) deltas (score after disclosure - scores at baseline). In patients with amyloid-positive SCD+, despite the small sample size, higher education was associated with lower disclosure-related distress (ρ = -0.43; P = .02) whereas the presence of study partner was associated with higher disclosure-related distress (W = 7.5; P = .03). No participants with amyloid-positive SCD+ showed probable presence of PTSD or severe anxiety or depression symptoms at follow-up. Conclusions and Relevance: The disclosure of a positive amyloid-PET result to patients with SCD+ was associated with a bigger psychological change, yet such change did not reach the threshold for clinical concern.


Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Male , Humans , Adult , Aged , Alzheimer Disease/diagnosis , Brain/metabolism , Amyloid beta-Peptides/metabolism , Prospective Studies , Disclosure , Positron-Emission Tomography , Cognitive Dysfunction/diagnostic imaging
11.
Alzheimers Res Ther ; 14(1): 125, 2022 09 06.
Article in English | MEDLINE | ID: mdl-36068621

ABSTRACT

BACKGROUND: Older individuals with subjective cognitive decline (SCD) perceive that their cognition has declined but do not show objective impairment on neuropsychological tests. Individuals with SCD are at elevated risk of objective cognitive decline and incident dementia. Non-pharmacological interventions (including mindfulness-based and health self-management approaches) are a potential strategy to maintain or improve cognition in SCD, which may ultimately reduce dementia risk. METHODS: This study utilized data from the SCD-Well randomized controlled trial. One hundred forty-seven older adults with SCD (MAge = 72.7 years; 64% female) were recruited from memory clinics in four European countries and randomized to one of two group-based, 8-week interventions: a Caring Mindfulness-based Approach for Seniors (CMBAS) or a health self-management program (HSMP). Participants were assessed at baseline, post-intervention (week 8), and at 6-month follow-up (week 24) using a range of cognitive tests. From these tests, three composites were derived-an "abridged" Preclinical Alzheimer's Cognitive Composite 5 (PACC5Abridged), an attention composite, and an executive function composite. Both per-protocol and intention-to-treat analyses were performed. Linear mixed models evaluated the change in outcomes between and within arms and adjusted for covariates and cognitive retest effects. Sensitivity models repeated the per-protocol analyses for participants who attended ≥ 4 intervention sessions. RESULTS: Across all cognitive composites, there were no significant time-by-trial arm interactions and no measurable cognitive retest effects; sensitivity analyses supported these results. Improvements, however, were observed within both trial arms on the PACC5Abridged from baseline to follow-up (Δ [95% confidence interval]: CMBAS = 0.34 [0.19, 0.48]; HSMP = 0.30 [0.15, 0.44]). There was weaker evidence of an improvement in attention but no effects on executive function. CONCLUSIONS: Two non-pharmacological interventions conferred small, non-differing improvements to a global cognitive composite sensitive to amyloid-beta-related decline. There was weaker evidence of an effect on attention, and no evidence of an effect on executive function. Importantly, observed improvements were maintained beyond the end of the interventions. Improving cognition is an important step toward dementia prevention, and future research is needed to delineate the mechanisms of action of these interventions and to utilize clinical endpoints (i.e., progression to mild cognitive impairment or dementia). TRIAL REGISTRATION: ClinicalTrials.gov, NCT03005652.


Subject(s)
Cognitive Dysfunction , Dementia , Mindfulness , Self-Management , Aged , Cognition , Cognitive Dysfunction/psychology , Dementia/prevention & control , Female , Humans , Male , Neuropsychological Tests
12.
Neurology ; 99(13): e1422-e1431, 2022 Sep 27.
Article in English | MEDLINE | ID: mdl-35853750

ABSTRACT

BACKGROUND AND OBJECTIVES: Self-reflection (the active evaluation of ones thoughts, feelings, and behaviors) can confer protection against adverse health outcomes. Its effect on markers sensitive to Alzheimer disease (AD), however, is unknown. The primary objective of this cross-sectional study was to examine the association between self-reflection and AD-sensitive markers. METHODS: This study used baseline data from cognitively unimpaired older adults enrolled in the Age-Well clinical trial and older adults with subjective cognitive decline from the SCD-Well clinical trial. In both cohorts, self-reflection was measured via the reflective pondering subscale of the Rumination Response Scale, global cognition assessed via the Preclinical Alzheimer's Cognitive Composite 5, and a modified late-life Lifestyle-for-Brain-Health (LIBRA) index computed to assess health and lifestyle factors. In Age-Well, glucose metabolism and amyloid deposition were quantified in AD-sensitive gray matter regions via fluorodeoxyglucose- and AV45-PET scans, respectively. Associations between self-reflection and AD-sensitive markers (global cognition, glucose metabolism, and amyloid deposition) were assessed via unadjusted and adjusted regressions. Furthermore, we explored whether associations were independent of health and lifestyle factors. To control for multiple comparisons in Age-Well, false discovery rate-corrected p values (p FDR) are reported. RESULTS: A total of 134 (mean age 69.3 ± 3.8 years, 61.9% women) Age-Well and 125 (mean age 72.6 ± 6.9 years, 65.6% women) SCD-Well participants were included. Across unadjusted and adjusted analyses, self-reflection was associated with better global cognition in both cohorts (Age-Well: adjusted-ß = 0.22, 95% CI 0.05-0.40, p FDR = 0.041; SCD-Well: adjusted-ß = 0.18, 95% CI 0.03-0.33, p = 0.023) and with higher glucose metabolism in Age-Well after adjustment for all covariates (adjusted-ß = 0.29, 95% CI 0.03-0.55, p FDR = 0.041). Associations remained following additional adjustment for LIBRA but did not survive false discovery rate (FDR) correction. Self-reflection was not associated with amyloid deposition (adjusted-ß = 0.13, 95% CI -0.07 to 0.34, p FDR = 0.189). DISCUSSION: Self-reflection was associated with better global cognition in 2 independent cohorts and with higher glucose metabolism after adjustment for covariates. There was weak evidence that relationships were independent from health and lifestyle behaviors. Longitudinal and experimental studies are warranted to elucidate whether self-reflection helps preserve cognition and glucose metabolism or whether reduced capacity to self-reflect is a harbinger of cognitive decline and glucose hypometabolism. TRIAL REGISTRATION INFORMATION: Age-Well: NCT02977819; SCD-Well: NCT03005652.


Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Aged , Alzheimer Disease/metabolism , Amyloid beta-Peptides/metabolism , Biomarkers/metabolism , Brain/diagnostic imaging , Brain/metabolism , Cognition/physiology , Cognitive Dysfunction/diagnostic imaging , Cognitive Dysfunction/metabolism , Cross-Sectional Studies , Female , Glucose/metabolism , Humans , Magnetic Resonance Imaging , Male , Positron-Emission Tomography
13.
Alzheimers Dement ; 2022 Jun 17.
Article in English | MEDLINE | ID: mdl-35715930

ABSTRACT

INTRODUCTION: AMYPAD Diagnostic and Patient Management Study (DPMS) aims to investigate the clinical utility and cost-effectiveness of amyloid-PET in Europe. Here we present participants' baseline features and discuss the representativeness of the cohort. METHODS: Participants with subjective cognitive decline plus (SCD+), mild cognitive impairment (MCI), or dementia were recruited in eight European memory clinics from April 16, 2018, to October 30, 2020, and randomized into three arms: ARM1, early amyloid-PET; ARM2, late amyloid-PET; and ARM3, free-choice. RESULTS: A total of 840 participants (244 SCD+, 341 MCI, and 255 dementia) were enrolled. Sociodemographic/clinical features did not differ significantly among recruiting memory clinics or with previously reported cohorts. The randomization assigned 35% of participants to ARM1, 32% to ARM2, and 33% to ARM3; cognitive stages were distributed equally across the arms. DISCUSSION: The features of AMYPAD-DPMS participants are as expected for a memory clinic population. This ensures the generalizability of future study results.

14.
Neuropsychol Rev ; 32(3): 677-702, 2022 09.
Article in English | MEDLINE | ID: mdl-34350544

ABSTRACT

Mindfulness-based programs (MBPs) are increasingly utilized to improve mental health. Interest in the putative effects of MBPs on cognitive function is also growing. This is the first meta-analysis of objective cognitive outcomes across multiple domains from randomized MBP studies of adults. Seven databases were systematically searched to January 2020. Fifty-six unique studies (n = 2,931) were included, of which 45 (n = 2,238) were synthesized using robust variance estimation meta-analysis. Meta-regression and subgroup analyses evaluated moderators. Pooling data across cognitive domains, the summary effect size for all studies favored MBPs over comparators and was small in magnitude (g = 0.15; [0.05, 0.24]). Across subgroup analyses of individual cognitive domains/subdomains, MBPs outperformed comparators for executive function (g = 0.15; [0.02, 0.27]) and working memory outcomes (g = 0.23; [0.11, 0.36]) only. Subgroup analyses identified significant effects for studies of non-clinical samples, as well as for adults aged over 60. Across all studies, MBPs outperformed inactive, but not active comparators. Limitations include the primarily unclear within-study risk of bias (only a minority of studies were considered low risk), and that statistical constraints rendered some p-values unreliable. Together, results partially corroborate the hypothesized link between mindfulness practices and cognitive performance. This review was registered with PROSPERO [CRD42018100904].


Subject(s)
Mindfulness , Adult , Aged , Cognition , Executive Function , Humans , Memory, Short-Term , Middle Aged , Mindfulness/methods
15.
Front Neurol ; 13: 1063598, 2022.
Article in English | MEDLINE | ID: mdl-36761917

ABSTRACT

Background: Amyloid-ß (Aß) accumulation is considered the earliest pathological change in Alzheimer's disease (AD). The Amyloid Imaging to Prevent Alzheimer's Disease (AMYPAD) consortium is a collaborative European framework across European Federation of Pharmaceutical Industries Associations (EFPIA), academic, and 'Small and Medium-sized enterprises' (SME) partners aiming to provide evidence on the clinical utility and cost-effectiveness of Positron Emission Tomography (PET) imaging in diagnostic work-up of AD and to support clinical trial design by developing optimal quantitative methodology in an early AD population. The AMYPAD studies: In the Diagnostic and Patient Management Study (DPMS), 844 participants from eight centres across three clinical subgroups (245 subjective cognitive decline, 342 mild cognitive impairment, and 258 dementia) were included. The Prognostic and Natural History Study (PNHS) recruited pre-dementia subjects across 11 European parent cohorts (PCs). Approximately 1600 unique subjects with historical and prospective data were collected within this study. PET acquisition with [18F]flutemetamol or [18F]florbetaben radiotracers was performed and quantified using the Centiloid (CL) method. Results: AMYPAD has significantly contributed to the AD field by furthering our understanding of amyloid deposition in the brain and the optimal methodology to measure this process. Main contributions so far include the validation of the dual-time window acquisition protocol to derive the fully quantitative non-displaceable binding potential (BP ND ), assess the value of this metric in the context of clinical trials, improve PET-sensitivity to emerging Aß burden and utilize its available regional information, establish the quantitative accuracy of the Centiloid method across tracers and support implementation of quantitative amyloid-PET measures in the clinical routine. Future steps: The AMYPAD consortium has succeeded in recruiting and following a large number of prospective subjects and setting up a collaborative framework to integrate data across European PCs. Efforts are currently ongoing in collaboration with ARIDHIA and ADDI to harmonize, integrate, and curate all available clinical data from the PNHS PCs, which will become openly accessible to the wider scientific community.

16.
Ageing Res Rev ; 72: 101505, 2021 12.
Article in English | MEDLINE | ID: mdl-34757173

ABSTRACT

Up to 40% of dementias may be preventable via risk factor modification. This inference has motivated the development of lifestyle interventions for reducing cognitive decline. Typically delivered to older adults face-to-face, the COVID-19 pandemic has necessitated their adaptation for remote delivery. We systematically reviewed randomized controlled trials of remotely delivered lifestyle interventions (≥4 weeks duration and delivered >50% remotely), for adults aged ≥ 60 without dementia, examining effects on objective cognitive measures. Comparators were active (face-to-face or remote) or passive. Ten studies (n = 2967) comprising multidomain (k = 4), physical activity (k = 3) or psychosocial (k = 3) remote interventions were included. Data were synthesized using robust variance estimation meta-analysis. The pooled estimate comparing the effect of remote interventions versus comparators on cognition was not significant (g=-0.02; 95%CI [-0.14, 0.09]; p = .66); subgroup analyses by type of intervention or comparator also yielded non-significant effects. Most studies had low risk of bias. Current evidence to support remote lifestyle interventions is limited. Included studies were conducted pre-pandemic, and evaluated individual, rather than group interventions. Future studies may exploit the greater digital connectivity of older people since the pandemic. Group formats, more frequently efficacious than individual interventions in face-to-face dementia prevention trials, may be a rational approach for future remote trials.


Subject(s)
COVID-19 , Dementia , Aged , Cognition , Humans , Life Style , Pandemics , SARS-CoV-2
17.
Alzheimers Dement (N Y) ; 7(1): e12172, 2021.
Article in English | MEDLINE | ID: mdl-33969179

ABSTRACT

INTRODUCTION: People living with dementia in nursing homes have complex needs; impairments in cognition, communication, and daily function; neuropsychiatric symptoms (NPS); and poor quality of life (QoL). The current study examines impairments in non-verbal communication as a potential driver of NPS and QoL. METHODS: One hundred nursing home residents with dementia were assessed using the Emory Dyssemia Index (EDI), Neuropsychiatric Inventory Nursing Home version (NPI-NH), Quality of Life in Alzheimer's Disease (QoL-AD) at baseline, 12-, and 24-week follow-up. RESULTS: The quantile regression (0.5) model indicated that impairment of non-verbal communication was independently associated with the severity of NPS (P = .001) and proxy reported QoL (P < .05), levels of agitation (P < .05), and professional caregiver burden (P < .05). DISCUSSION: These results highlight a novel potential approach to improve NPS and QoL using retained elements of non-verbal communication, particularly for people with severe dementia.

18.
Psychother Psychosom ; 90(5): 341-350, 2021.
Article in English | MEDLINE | ID: mdl-33873195

ABSTRACT

INTRODUCTION: Older adults experiencing subjective cognitive decline (SCD) have a heightened risk of developing dementia and frequently experience subclinical anxiety, which is itself associated with dementia risk. OBJECTIVE: To understand whether subclinical anxiety symptoms in SCD can be reduced through behavioral interventions. METHODS: SCD-Well is a randomized controlled trial designed to determine whether an 8-week mindfulness-based intervention (caring mindfulness-based approach for seniors; CMBAS) is superior to a structurally matched health self-management program (HSMP) in reducing subclinical anxiety. Participants were recruited from memory clinics at 4 European sites. The primary outcome was change in anxiety symptoms (trait subscale of the State-Trait Anxiety Inventory; trait-STAI) from pre- to postintervention. Secondary outcomes included a change in state anxiety and depression symptoms postintervention and 6 months postrandomization (follow-up). RESULTS: One hundred forty-seven participants (mean [SD] age: 72.7 [6.9] years; 64.6% women; CMBAS, n = 73; HSMP, n = 74) were included in the intention-to-treat analysis. There was no difference in trait-STAI between groups postintervention (adjusted change difference: -1.25 points; 95% CI -4.76 to 2.25) or at follow-up (adjusted change difference: -0.43 points; 95% CI -2.92 to 2.07). Trait-STAI decreased postintervention in both groups (CMBAS: -3.43 points; 95% CI -5.27 to -1.59; HSMP: -2.29 points; 95% CI -4.14 to -0.44) and reductions were maintained at follow-up. No between-group differences were observed for change in state anxiety or depression symptoms. CONCLUSIONS: A time-limited mindfulness intervention is not superior to health self-management in reducing subclinical anxiety symptoms in SCD. The sustained reduction observed across both groups suggests that subclinical anxiety symptoms in SCD are modifiable. ClinicalTrials.gov identifier: NCT03005652.


Subject(s)
Cognitive Dysfunction , Mindfulness , Self-Management , Aged , Anxiety/therapy , Anxiety Disorders , Cognitive Dysfunction/therapy , Female , Humans , Male
19.
Article in English | MEDLINE | ID: mdl-33542085

ABSTRACT

PURPOSE: The aim of this study was to re-evaluate the differentiation of patients with dementia with Lewy bodies (DLB) from Alzheimer's disease (AD) and Parkinson's disease (PD) using a quantitative analysis of 123I-FP-CIT SPECT scans. METHODS: Thirty-six patients with in vivo 123I-FP-CIT SPECT and neuropathological diagnoses were included. Based on neuropathological criteria, patients were further subclassified into nine AD, eight DLB, ten PD and nine with other diagnoses. An additional 16 healthy controls (HC) scanned with 123I-FP-CIT SPECT were also included. All images were visually assessed as normal versus abnormal uptake by consensus of five nuclear medicine physicians. Bihemispheric mean was calculated for caudate binding potential (CBP), putamen binding potential (PBP) and putamen-to-caudate ratio (PCR). RESULTS: Patients with DLB had significantly lower CBP and PBP than patients with AD and significantly higher PCR than patients with PD. Qualitative visual analysis of the images gave an accuracy of 88% in the evaluation of the status of the nigrostriatal pathway considering all individuals, and 96% considering only the patients with PD, AD and DLB. Quantitative analyses provided a balanced accuracy of 94%, 94% and 100% in binary classifications DLB versus AD, DLB versus PD and PD versus AD, respectively, and an accuracy of 93% in the differentiation among patients with DLB, AD and PD simultaneously. No statistically significant differences were observed between the AD and HC. CONCLUSIONS: This study demonstrates a very high diagnostic accuracy of the quantitative analysis of(123I-FP-CIT SPECT data to differentiate among patients with DLB, PD and AD.

20.
Alzheimers Res Ther ; 13(1): 47, 2021 02 17.
Article in English | MEDLINE | ID: mdl-33597002

ABSTRACT

BACKGROUND: Type 2 diabetes is a risk factor for Alzheimer's disease (AD), and AD brain shows impaired insulin signalling. The role of peripheral insulin resistance on AD aetiopathogenesis in non-diabetic patients is still debated. Here we evaluated the influence of insulin resistance on brain glucose metabolism, grey matter volume and white matter lesions (WMLs) in non-diabetic AD subjects. METHODS: In total, 130 non-diabetic AD subjects underwent MRI and [18F]FDG PET scans with arterial cannula insertion for radioactivity measurement. T1 Volumetric and FLAIR sequences were acquired on a 3-T MRI scanner. These subjects also had measurement of glucose and insulin levels after a 4-h fast on the same day of the scan. Insulin resistance was calculated by the updated homeostatic model assessment (HOMA2). For [18F]FDG analysis, cerebral glucose metabolic rate (rCMRGlc) parametric images were generated using spectral analysis with arterial plasma input function. RESULTS: In this non-diabetic AD population, HOMA2 was negatively associated with hippocampal rCMRGlc, along with total grey matter volumes. No significant correlation was observed between HOMA2, hippocampal volume and WMLs. CONCLUSIONS: In non-diabetic AD, peripheral insulin resistance is independently associated with reduced hippocampal glucose metabolism and with lower grey matter volume, suggesting that peripheral insulin resistance might influence AD pathology by its action on cerebral glucose metabolism and on neurodegeneration.


Subject(s)
Alzheimer Disease , Diabetes Mellitus, Type 2 , Insulin Resistance , Alzheimer Disease/complications , Alzheimer Disease/diagnostic imaging , Brain/diagnostic imaging , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/diagnostic imaging , Fluorodeoxyglucose F18 , Glucose , Humans , Magnetic Resonance Imaging , Positron-Emission Tomography
SELECTION OF CITATIONS
SEARCH DETAIL
...