Abstract: Background: Although dementia with Lewy bodies (DLB) is a degenerative disease involving irreversible pathological changes and subsequent progressive cognitive decline, some patients have presented with improved cognitive function at follow-ups. Their clinical and neuropsychological characteristics and the factors influencing this improvement remain unclear. Objective: To investigate differences in clinical and neuropsychological characteristics between DLB patients with and without cognitive improvement at a one-year follow-up, and to identify predictive factors of cognitive improvement. Methods: This retrospective study included 60 DLB patients, 28 patients in the improved group, and 32 patients in the non-improved group. A multiple linear regression model was used…to compare changes in cognitive function test scores between groups over the course of one year. Binary logistic regression analysis was performed to determine the odds ratios (ORs) of depressive symptoms as a predictor for cognitive improvement. Results: The improved group showed significant increases in immediate and delayed verbal memory function in one year over the non-improved group. We also found that baseline depressive symptoms were associated with an increased probability of cognitive improvement (OR 1.234, CI 1.043– 1.460). Conclusion: Depressive symptoms at baseline were related to a higher probability of a cognitive improvement at one-year follow-up. In addition, immediate and delayed verbal memory function showed significant improvement during one year in improved patients compared to non-improved patients.
Show more
Keywords: Cognitive improvement, dementia with Lewy bodies, depressive symptoms
Abstract: Background: Sundown syndrome (SS) in patients with Alzheimer’s disease (AD) is characterized by aggravation of behavioral problems at sunset. Disturbance of the circadian rhythm, a possible cause of SS, also facilitates amyloidopathy and reduces sleep quality. However, the associations of SS with amyloidopathy and sleep quality remain unclear. Objective: To investigate the prevalence of SS in patients with AD, the association between SS and APOE ɛ 4 carrier, representing an enhanced amyloid pathology, and the relationship between SS and sleep quality in AD. Methods: We included 104 patients with late-onset AD and known APOE genotype. All participants underwent a structured…interview via informant-based questionnaires to assess sleep quality and the presence of SS. Binary logistic regression analysis was performed to determine odds ratios (ORs) of APOE ɛ 4 carrier and parameters of sleep quality for SS. Results: The prevalence of SS in AD was 27.8% (n = 29). Patients with SS were significantly more likely to be APOE ɛ 4 carriers and to have rapid eye movement sleep behavior disorder (RBD) and a higher Clinical Dementia Rating (CDR) score compared to those without SS. In the multivariate regression analysis, APOE ɛ 4 carrier (OR 3.158, CI 1.022–9.758), RBD (OR 2.166, CI 1.073–4.371), and higher CDR score (OR 2.453, CI 1.084–5.550) were associated with an increased risk of SS. Conclusion: The prevalence of SS in patients with AD was 27.8%. The presence of the APOE ɛ 4 allele, RBD, and more severe dementia are associated with an increased risk of SS in AD.
Show more
Abstract: Amyloid-β (Aβ) is a key protein in Alzheimer’s disease (AD) in that its accumulation induces complex pathological changes. Although there has been extensive research on the metabolism of Aβ in AD, new compelling results have recently emerged. Historically, the production and clearance of Aβ have been thought to originate in the central nervous system (CNS). However, recent evidence suggests that the production and clearance of Aβ can also occur in the peripheral system, and that the peripherally driven Aβ migrates to the CNS and induces amyloidopathy with subsequent AD pathologic changes in the brain. This concept implies that AD is…not restricted to the CNS but is a systemic disease instead. As such, the development of blood-based biomarkers targeting Aβ is of great interest. Central and peripheral Aβ are both active contributors to the pathology of AD and interact bidirectionally. Measuring peripheral Aβ is not just observing the reflection of the residual Aβ removed from the CNS but also tracking the ongoing process of AD pathology. Additionally, blood-based biomarkers could be a more accessible tool in clinical and research settings. Through arduous research, several blood-based biomarker assays have demonstrated notable results. In this review, we describe the metabolism of Aβ and the amyloid-targeting blood-based biomarkers of AD.
Show more
Abstract: BACKGROUND: The upright head roll test (UHRT) is a recently introduced diagnostic maneuver for lateral semicircular canal benign paroxysmal positional vertigo (LSC-BPPV). OBJECTIVE: This study aimed to evaluate the reliability and validity of the UHRT. METHODS: Two separate studies were conducted. Study 1 analyzed 827 results of videonystagmography (VNG) to assess UHRT reliability, and Study 2 analyzed 130 LSC-BPPV cases to evaluate UHRT validity. RESULTS: The inter-test reliability between UHRT and the supine head roll test (SHRT) showed substantial agreement (Cohen’s kappa = 0.753) in direction-changing positional nystagmus (DCPN) and almost perfect agreement (Cohen’s kappa = 0.836) in distinguishing the direction of DCPN. The…validity assessment of UHRT showed high accuracy in diagnosing LSC-BPPV (80.0%) and in differentiating the variant types (74.6%). UHRT was highly accurate in diagnosing the canalolithiasis type in LSC-BPPV patients (Cohen’s kappa = 0.835); however, it showed only moderate accuracy in diagnosing the cupulolithiasis type (Cohen’s kappa = 0.415). The intensity of nystagmus in UHRT was relatively weaker than that in SHRT (P < 0.05). CONCLUSION: UHRT is a reliable test for diagnosing LSC-BPPV and distinguishing subtypes. However, UHRT has a limitation in discriminating the affected side owing to a weaker intensity of nystagmus than SHRT.
Show more
Abstract: Background: Oligomeric amyloid-β (Aβ) is one of the major contributors to the pathomechanism of Alzheimer’s disease (AD); Aβ oligomerization in plasma can be measured using a Multimer Detection System-Oligomeric Aβ (MDS-OAβ) after incubation with spiked synthetic Aβ. Objective: We evaluated the clinical sensitivity and specificity of the MDS-OAβ values for prediction of AD. Methods: The MDS-OAβ values measured using inBlood™ OAβ test in heparin-treated plasma samples from 52 AD patients in comparison with 52 community-based subjects with normal cognition (NC). The inclusion criterion was proposed by the NINCDS-ADRDA and additionally required at least 6 months of follow-up from the initial…clinical diagnosis in the course of AD. Results: The MDS-OAβ values were 1.43±0.30 ng/ml in AD and 0.45±0.19 (p < 0.001) in NC, respectively. Using a cut-off value of 0.78 ng/ml, the results revealed 100% sensitivity and 92.31% specificity. Conclusion: MDS-OAβ to measure plasma Aβ oligomerization is a valuable blood-based biomarker for clinical diagnosis of AD, with high sensitivity and specificity.
Show more