Your search for: 'collaborators:("Mah, L.")' has returned 8 results. (0.103s) Save search

Authors: Zawar, Ifrah | Mattos, Meghan K. | Manning, Carol | Patrie, James | Quigg, Mark

Article Type: Research Article

Abstract: Background: The effect of nighttime behaviors on cognition has not been studied independently from other neuropsychiatric symptoms. Objective: We evaluate the following hypotheses that sleep disturbances bring increased risk of earlier cognitive impairment, and more importantly that the effect of sleep disturbances is independent from other neuropsychiatric symptoms that may herald dementia. Methods: We used the National Alzheimer’s Coordinating Center database to evaluate the relationship between Neuropsychiatric Inventory Questionnaire (NPI-Q) determined nighttime behaviors which served as surrogate for sleep disturbances and cognitive impairment. Montreal Cognitive Assessment scores defined two groups: conversion from 1) normal to mild cognitive impairment (MCI) and …2) MCI to dementia. The effect of nighttime behaviors at initial visit and covariates of age, sex, education, race, and other neuropsychiatric symptoms (NPI-Q), on conversion risk were analyzed using Cox regression. Results: Nighttime behaviors predicted earlier conversion time from normal cognition to MCI (hazard ratio (HR): 1.09; 95% CI: [1.00, 1.48], p  = 0.048) but were not associated with MCI to dementia conversion (HR: 1.01; [0.92, 1.10], p  = 0.856). In both groups, older age, female sex, lower education, and neuropsychiatric burden increased conversion risk. Conclusion: Our findings suggest that sleep disturbances predict earlier cognitive decline independently from other neuropsychiatric symptoms that may herald dementia. Show more

Keywords: Dementia, mild cognitive impairment, neuropsychiatric symptoms, nighttime behaviors, sleep disturbances

DOI: 10.3233/JAD-221244

Citation: Journal of Alzheimer's Disease, vol. 92, no. 4, pp. 1427-1438, 2023

Authors: Gerritsen, Adrie A.J. | Bakker, Christian | Verhey, Frans R.J. | Bor, Hans | Pijnenburg, Yolande A.L. | de Vugt, Marjolein E. | Koopmans, Raymond T.C.M.

Article Type: Research Article

Abstract: Background: The progression of dementia in people with young-onset dementia (YOD) is relatively unknown. Objective: To investigate the progression of dementia and cognitive decline in the three most common subtypes in YOD and to explore which factors are associated with this course. Methods: The course of dementia was examined in 198 people with YOD. The primary outcomes were cognitive function, as assessed by the Mini-Mental State Examination (MMSE) and dementia severity, as assessed by the Global Deterioration Scale (GDS). Mixed-model analyses were used to explore factors associated with the course of dementia of the diagnostic sub-types. Results: The mean overall …two-year progression of dementia severity was 0.9 GDS points, this was a statistically significant change (p  = 0.012) and was not significantly different for the three dementia subtypes. The mean overall two-year decline in cognitive function was 1.6 points on the MMSE. The differences in cognitive decline were statistically significant (p  = 0.046) among the three diagnosis groups, AD participants showed the greatest decline, of 2.3 points. In addition to lower education (p  = 0.010), higher scores on the Neuropsychiatric Inventory (NPI) sub-syndromes psychosis (p  < 0.001) and hyperactivity (p  = 0.002) were associated with higher rates of cognitive decline. In contrast, higher scores on the NPI affect cluster were associated with lower levels of cognitive decline (p  < 0.001). Conclusion: Different YOD subtypes show different rates of decline in cognitive functioning, and this decline seems less progressive compared to those observed in studies in late-onset AD. Further research is needed to evaluate whether managing neuropsychiatric symptoms can positively influence the decline of cognitive function. Show more

Keywords: Cognitive decline, progression of dementia, young onset dementia

DOI: 10.3233/JAD-170859

Citation: Journal of Alzheimer's Disease, vol. 63, no. 1, pp. 343-351, 2018

Authors: Geng, Zhi | Wu, Yue | Liu, Jiaqiu | Zhan, Yuqian | Yan, Yibing | Yang, Chaoyi | Pang, Xuerui | Ji, Yi | Gao, Manman | Zhou, Shanshan | Wei, Ling | Hu, Panpan | Wu, Xingqi | Tian, Yanghua | Wang, Kai

Article Type: Research Article

Abstract: Background: Alzheimer’s disease (AD) is a neurodegenerative disease characterized by brain network dysfunction. Few studies have investigated whether the functional connections between executive control networks (ECN) and other brain regions can predict the therapeutic effect of repetitive transcranial magnetic stimulation (rTMS). Objective: The purpose of this study is to examine the relationship between the functional connectivity (FC) within ECN networks and the efficacy of rTMS. Methods: We recruited AD patients for rTMS treatment. We established an ECN using baseline period fMRI data and conducted an analysis of the ECN’s FC throughout the brain. Concurrently, the support vector regression (SVR) method …was employed to project post-rTMS cognitive scores, utilizing the connectional attributes of the ECN as predictive markers. Results: The average age of the patients was 66.86±8.44 years, with 8 males and 13 females. Significant improvement on most cognitive measures. We use ECN connectivity and brain region functions in baseline patients as features for SVR model training and fitting. The SVR model could demonstrate significant predictability for changes in Montreal Cognitive Assessment scores among AD patients after rTMS treatment. The brain regions that contributed most to the prediction of the model (the top 10% of weights) were located in the medial temporal lobe, middle temporal gyrus, frontal lobe, parietal lobe and occipital lobe. Conclusions: The stronger the antagonism between ECN and parieto-occipital lobe function, the better the prediction of cognitive improvement; the stronger the synergy between ECN and fronto-temporal lobe function, the better the prediction of cognitive improvement. Show more

Keywords: Alzheimer’s disease, executive control network, functional connectivity, repetitive transcranial magnetic stimulation, support vector regression

DOI: 10.3233/JAD-231449

Citation: Journal of Alzheimer's Disease, vol. 99, no. 4, pp. 1349-1359, 2024

Authors: Sinclair, Lindsey I. | Lawton, Michael A. | Palmer, Jennifer C. | Ballard, Clive G.

Article Type: Research Article

Abstract: Background: Depression in individuals with Alzheimer’s disease (AD) is common, distressing, difficult to treat, and inadequately understood. It occurs more frequently in AD than in older adults without dementia. The reasons why some patients develop depression during AD and others do not remain obscure. Objective: We aimed to characterize depression in AD and to identify risk factors. Methods: We used data from three large dementia focused cohorts: ADNI (n  = 665 with AD, 669 normal cognition), NACC (n  = 698 with AD, 711 normal cognition), and BDR (n  = 757 with AD). Depression ratings were available using the GDS and NPI and in …addition for BDR the Cornell. A cut-off of≥8 was used for the GDS and the Cornell Scale for Depression in Dementia,≥6 for the NPI depression sub-scale, and≥2 for the NPI-Q depression sub-scale. We used logistic regression to examine potential risk factors and random effects meta-analysis and an interaction term to look for interactions between each risk factor and the presence of cognitive impairment. Results: In individual studies there was no evidence of a difference in risk factors for depressive symptoms in AD. In the meta-analysis the only risk factor which increased the risk of depressive symptoms in AD was previous depression, but information on this was only available from one study (OR 7.78 95% CI 4.03–15.03). Conclusion: Risk factors for depression in AD appear to differ to those for depression per se supporting suggestions of a different pathological process, although a past history of depression was the strongest individual risk factor. Show more

Keywords: Alzheimer’s disease, dementia, depression, depressive disorder

DOI: 10.3233/ADR-239000

Citation: Journal of Alzheimer's Disease Reports, vol. 7, no. 1, pp. 213-225, 2023

Authors: Chen, Yu-si | Shu, Kai | Kang, Hui-cong

Article Type: Review Article

Abstract: Alzheimer’s disease (AD) is becoming a prevalent disease in the elderly population. Past decades have witnessed the development of drug therapies with varying targets. However, all drugs with a single molecular target fail to reverse or ameliorate AD progression, which ultimately results in cortical and subcortical network dysregulation. Deep brain stimulation (DBS) has been proven effective for the treatment of Parkinson’s disease, essential tremor, and other neurological diseases. As such, DBS has also been gradually acknowledged as a potential therapy for AD. The current review focuses on DBS of the nucleus basalis of Meynert (NBM). As a critical component of …the cerebral cholinergic system and the Papez circuit in the basal ganglia, the NBM plays an indispensable role in the subcortical regulation of memory, attention, and arousal state, which makes the NBM a promising target for modulation of neural network dysfunction and AD treatment. We summarized the intricate projection relations and functionality of the NBM, current approaches for stereotactic localization and evaluation of the NBM, and the therapeutic effects of NBM-DBS both in patients and animal models. Furthermore, the current shortcomings of NBM-DBS, such as variations in cortical blood flow, increased temperature in the target area, and stimulation-related neural damage, were presented. Show more

Keywords: Alzheimer’s disease, deep brain stimulation, functional neurosurgery, neuromodulation, nucleus basalis of Meynert, technical consideration

DOI: 10.3233/JAD-201141

Citation: Journal of Alzheimer's Disease, vol. 80, no. 1, pp. 53-70, 2021

Authors: Gaubert, Fanny | Borg, Céline | Chainay, Hanna

Article Type: Research Article

Abstract: Background: Alzheimer’s disease (AD) negatively impacts patients’ ability to make advantageous decisions, i.e., a core ability contributing to the preservation of autonomy. Objective: The present study aims to analyze the changes that occur in the decision-making competence (DMC) in AD patients and to determine if these changes are related to the deterioration of executive functions and working memory. Method: To this end, 20 patients with AD and 20 elderly control adults were assessed using executive, working memory, and DMC tasks. The latter comprised the Iowa Gambling Task (IGT) and a scenarios task based on situations inspired by everyday life and …performed under conditions of risk and ambiguity. Results: Results revealed lower performances in AD patients than in elderly control adults for all the tasks assessing cognitive functions. The AD patients also made more strategy changes during the IGT. In the scenarios tasks, the two groups took as many ambiguous or risky decisions, but AD patients tended to take more risks in the context of gain than elderly control adults did. Switching and updating ability, as well as working memory, appeared to be involved in decisions in tasks inspired by everyday life, while inhibition was more related to the IGT performances. Conclusion: Working memory and executive functions seem to be involved in decision-making, but in different ways in gambling and daily-life situations. Show more

Keywords: Alzheimer’s disease, decision making, executive function, working memory

DOI: 10.3233/JAD-220581

Citation: Journal of Alzheimer's Disease, vol. 90, no. 4, pp. 1793-1815, 2022

Authors: Sharon, Donald | Chen, Rui | Snyder, Michael

Article Type: Research Article

Abstract: Our understanding of human disease and potential therapeutics is improving rapidly. In order to take advantage of these developments it is important to be able to identify disease markers. Many new high-throughput genomics and proteomics technologies are being implemented to identify candidate disease markers. These technologies include protein microarrays, next-generation DNA sequencing and mass spectrometry platforms. Such methods are particularly important for elucidating the repertoire of molecular markers in the genome, transcriptome, proteome and metabolome of patients with diseases such as cancer, autoimmune diseases, and viral infections, resulting from the disruption of many biological pathways. These new technologies have identified …many potential disease markers. These markers are expected to be valuable to achieve the promise of truly personalized medicine. Show more

Keywords: Systems biology, disease markers, cancer, autoimmune disease, protein microarray, mass spectrometry, Next-generation sequencing

DOI: 10.3233/DMA-2010-0707

Citation: Disease Markers, vol. 28, no. 4, pp. 209-224, 2010

Authors: Johnson, Carrie E. | Duncan, Marilyn J. | Murphy, M. Paul

Article Type: Review Article

Abstract: Alzheimer’s disease (AD) affects more women than men, with women throughout the menopausal transition potentially being the most under researched and at-risk group. Sleep disruptions, which are an established risk factor for AD, increase in prevalence with normal aging and are exacerbated in women during menopause. Sex differences showing more disrupted sleep patterns and increased AD pathology in women and female animal models have been established in literature, with much emphasis placed on loss of circulating gonadal hormones with age. Interestingly, increases in gonadotropins such as follicle stimulating hormone are emerging to be a major contributor to AD pathogenesis and …may also play a role in sleep disruption, perhaps in combination with other lesser studied hormones. Several sleep influencing regions of the brain appear to be affected early in AD progression and some may exhibit sexual dimorphisms that may contribute to increased sleep disruptions in women with age. Additionally, some of the most common sleep disorders, as well as multiple health conditions that impair sleep quality, are more prevalent and more severe in women. These conditions are often comorbid with AD and have bi-directional relationships that contribute synergistically to cognitive decline and neuropathology. The association during aging of increased sleep disruption and sleep disorders, dramatic hormonal changes during and after menopause, and increased AD pathology may be interacting and contributing factors that lead to the increased number of women living with AD. Show more

Keywords: Alzheimer’s disease, hormones, menopause, sex differences, sleep, women

DOI: 10.3233/JAD-230527

Citation: Journal of Alzheimer's Disease, vol. 97, no. 1, pp. 31-74, 2024