| 1. |
- Wallert, John, et al.
(författare)
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The worst performance rule with elderly in abnormal cognitive decline
- 2017
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Ingår i: Intelligence. - : Elsevier. - 0160-2896 .- 1873-7935. ; 64, s. 9-17
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Tidskriftsartikel (refereegranskat)abstract
- Compared to best performances, worst performances on multi-trial psychometric tests often show stronger correlations with other g-loaded cognitive tests, which is known as the Worst Performance Rule (WPR). While worst performances may be more sensitive or specific to cognitive decline, clinical psychometric research and neuropsychological practice tends to neglect the WPR. Here, we examined the WPR-paradigm relative to abnormal cognitive decline. Specifically, we studied the WPR with binned simple reaction time task responses when rank-correlated with five different estimates of psychometric g within a memory clinic sample (n = 103) of elderly diagnosed with either Mild Cognitive Impairment (MCI) (n = 53) or dementia (n = 50). Three of the g-estimates were composite scores constructed from 2, 6, and 28 established test scores. Results showed a consistent WPR-pattern in the whole sample for each of the five estimates (block design rs = − 0.201 to − 0.120; digit span rs = − 0.284 to − 0.112; g2 rs = − 0.311 to − 0.162; g6 rs = − 0.314 to − 0.107; g28 rs = − 0.269 to − 0.121). Our findings contradict classical test theory, and highlight the underused potential of the WPR when assessing cognitive dysfunction in elderly patients.
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| 2. |
- Ekman, Urban, et al.
(författare)
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Evaluation of a Novel Psychological Intervention Tailored for Patients With Early Cognitive Impairment (PIPCI) : Study Protocol of a Randomized Controlled Trial
- 2020
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Ingår i: Frontiers in Psychology. - : Frontiers Media SA. - 1664-1078. ; 11
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Tidskriftsartikel (refereegranskat)abstract
- Background: Individuals with early phase cognitive impairment are frequently affected by existential distress, social avoidance and associated health issues (including symptoms of stress, anxiety, and depression). The demand for efficient psychological support is crucial from both an individual and a societal perspective. We have developed a novel psychological intervention (Psychological Intervention tailored for Patients with Cognitive Impairment, PIPCI) manual for providing a non-medical path to enhanced psychological health in the cognitively impaired population. The current article provides specific information on the randomized controlled trial (RCT)-design and methods. The main hypothesis is that participants receiving PIPCI will increase their psychological flexibility (the ability to notice and accept interfering thoughts, emotions, and bodily sensations without acting on them, when this serves action in line with personal values) compared to participants in the active control (cognitive training) group and the waiting list control group. The secondary hypotheses are that participants receiving PIPCI will improve psychological health (stress measures, quality of life, depression, and general health) compared to participants in the active control group and the waiting list control group.Materials and Methods: This three-arm RCT will recruit participants from the cognitive centers at Karolinska University Hospital in Stockholm and randomize approximately 120 individuals in the early phase of cognitive impairment to either an experimental group (psychological intervention once a week for 10 weeks), an active control group (cognitive training once a week for 10 weeks) or a waiting list control group. Intervention outcome will be evaluated with self-report questionnaires on physical and psychological aspects of health, cognitive assessment, biological markers (obtained from blood and saliva) and health care costs. Assessments will be performed at pre- (1 week before the interventions) and post-intervention (1 week after the interventions), as well as at a 6-month follow-up.Discussion: The development of a potentially feasible and effective psychological intervention tailored for early phase cognitive impairment (PIPCI) has the potential to advance the non-pharmacological intervention field. This is especially important given the extensive burden for many affected individuals and their families and the current lack of effective treatments. If the psychological intervention discussed here shows feasibility and efficacy, there is potential for far-reaching healthcare implications for patients with early cognitive impairment at risk of developing dementia.
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| 3. |
- Li, Xiaozhen, et al.
(författare)
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The Effects of Gene Mutations on Default Mode Network in Familial Alzheimer’s Disease
- 2017
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Ingår i: Journal of Alzheimer's Disease. - 1387-2877 .- 1875-8908. ; 56:1, s. 327-334
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Tidskriftsartikel (refereegranskat)abstract
- Familial Alzheimer’s disease (FAD) mutations have very high penetrance but age at onset and rate of disease progression differ. Neuroimaging and cerebrospinal fluid (CSF) examinations in mutation carriers (MCs) may provide an opportunity to identify early biomarkers that can be used to track disease progression from presymptomatic to the dementia stages of disease. The default mode network (DMN) is a resting state neuronal network composed of regions known to associate with amyloid deposition in AD. We hypothesized that functional connectivity in the DMN might change at pre-clinical stages in FAD MCs and correlate with changes in CSF biomarkers as a consequence of AD brain pathology. To test the hypothesis, we compared the functional connectivity in DMN between pre-MCs/MCs and non-carriers (NCs). No significant differences between pre-MCs and NCs were observed. When comparing all MCs with NCs, significant decreased functional connectivity in the right inferior parietal lobule, right precuneus, and left posterior cingulate cortex were found. We also found statistically significant correlations between CSF amyloid-β 42 and tau protein levels and average Z-score, a resting-state functional MRI measurement reflecting the degree of the correlation between a given voxel’s time courses and the time courses corresponding to DMN, from the region with statistical difference. The observed disruption of DMN and pathological levels of AD CSF-biomarkers in FAD MCs are similar to the changes described in sporadic AD, which give further support that amyloid and tau pathology impairs neuronal and synaptic function.
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| 4. |
- Thordardottir, Steinunn, et al.
(författare)
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Reduced penetrance of the PSEN1 H163Y autosomal dominant Alzheimer mutation : A 22-year follow-up study
- 2018
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Ingår i: Alzheimer's Research & Therapy. - : Springer Science and Business Media LLC. - 1758-9193. ; 10
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Tidskriftsartikel (refereegranskat)abstract
- Background: The range of onset ages within some PSEN1 families is wide, and a few cases of reduced penetrance of PSEN1 mutations have been reported. However, published data on reduced penetrance have been limited to clinical histories, often collected retrospectively and lacking biomarker information. We present a case of reduced penetrance of the PSEN1 H163Y mutation in a carrier prospectively followed for 22 years. Methods: Two brothers (A and B), both carriers of the H163Y mutation, were followed between 1995 and 2017. They underwent repeated clinical evaluations, neuropsychological assessments, and cerebrospinal fluid analyses, as well as brain imaging examinations with structural magnetic resonance, [F-18] fluorodeoxyglucose positron emission tomography, and [C-11] Pittsburgh compound B positron emission tomography. Results: Brother A was followed between 44 and 64 years of age. Cognitive symptoms due to Alzheimer's disease set in at the age of 54. Gradual worsening of symptoms resulted in admittance to a nursing home owing to dependence on others for all activities of daily living. He showed a curvilinear decline in cognitive function on neuropsychological tests, and changes on magnetic resonance imaging, positron emission tomography, and biomarkers in the cerebrospinal fluid supported a clinical diagnosis of Alzheimer's disease. Brother A died at the age of 64 and fulfilled the criteria for definitive Alzheimer's disease according to neuropathological examination results. Brother B was followed between the ages of 43 and 65 and showed no cognitive deterioration on repeated neuropsychological test occasions. In addition, no biomarker evidence of Alzheimer's disease pathology was detected, either on imaging examinations or in cerebrospinal fluid. Conclusions: The average (SD) age of symptom onset for PSEN1 H163Y is 51 +/- 7 years according to previous studies. However, we present a case of a biomarker-verified reduction in penetrance in a mutation carrier who was still symptom-free at the age of 65. This suggests that other genetic, epigenetic, and/or environmental factors modify the onset age.
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| 5. |
- Vilaplana, Eduard, et al.
(författare)
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Cortical microstructural correlates of astrocytosis in autosomal-dominant Alzheimer disease
- 2020
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Ingår i: Neurology. - : LIPPINCOTT WILLIAMS & WILKINS. - 0028-3878 .- 1526-632X. ; 94:19, s. e2026-E2036
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To study the macrostructural and microstructural MRI correlates of brain astrocytosis, measured with C-11-deuterium-L-deprenyl (C-11-DED)-PET, in familial autosomal-dominant Alzheimer disease (ADAD).Methods: The total sample (n = 31) comprised ADAD mutation carriers (n = 10 presymptomatic, 39.2 10.6 years old; n = 3 symptomatic, 55.5 2.0 years old) and noncarriers (n = 18, 44.0 +/- 13.7 years old) belonging to families with mutations in either the presenilin-1 or amyloid precursor protein genes. All participants underwent structural and diffusion MRI and neuropsychological assessment, and 20 participants (6 presymptomatic and 3 symptomatic mutation carriers and 11 noncarriers) also underwent C-11-DED-PET.Results: Vertex-wise interaction analyses revealed a differential relationship between carriers and noncarriers in the association between C-11-DED binding and estimated years to onset (EYO) and between cortical mean diffusivity (MD) and EYO. These differences were due to higher C-11-DED binding in presymptomatic carriers, with lower binding in symptomatic carriers compared to noncarriers, and to lower cortical MD in presymptomatic carriers, with higher MD in symptomatic carriers compared to noncarriers. Using a vertex-wise local correlation approach, C-11-DED binding was negatively correlated with cortical MD and positively correlated with cortical thickness.Conclusions: Our proof-of-concept study is the first to show that microstructural and macrostructural changes can reflect underlying neuroinflammatory mechanisms in early stages of Alzheimer disease (AD). The findings support a role for neuroinflammation in AD pathogenesis, with potential implications for the correct interpretation of neuroimaging biomarkers as surrogate endpoints in clinical trials.
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