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OBJECTIVE: Most neurodegenerative dementias present with substantial overlap in clinical features. Therefore, differential diagnosis is often a challenging task necessitating costly and sometimes invasive diagnostic procedures. A promising, non-invasive and cost-effective method is the widely available electroencephalography (EEG). METHODS: Twenty-three subjects with Alzheimer's disease (AD), 28 subjects with dementia with Lewy bodies (DLB), 15 subjects with frontotemporal dementias (FTDs), and 22 healthy controls (HC) were enrolled. Nineteen channel computerized EEG recordings were acquired. Mean relative powers were calculated using the standard frequency bands. Theta/alpha ratio (TAR), theta/beta ratio (TBR), a spectral index of (alpha + beta)/(theta + delta) and an alpha reactivity index (alpha in eyes-open condition/alpha in eyes-closed condition) were also calculated. Receiver operating characteristic (ROC) analyses were performed to assess diagnostic accuracy. RESULTS: For the comparison of EEG measures across groups, we performed a multivariate ANOVA followed by univariate ANOVAs controlling for the effects of age, with post hoc tests. Theta power and TBR were increased in DLB compared to other groups. Alpha power was decreased in DLB compared to HC and FTD; and in AD compared to FTD. Beta power was decreased in DLB compared to AD and HC. Furthermore, regional analyses demonstrated a unique pattern of theta power increase in DLB; affecting frontal, central, parietal, occipital, and temporal regions. In AD, theta power increased compared to HC in parietal, occipital, and right temporal regions. TAR was increased in DLB compared to other groups; and in AD compared to HC. Finally, alpha reactivity index was higher in DLB compared to HC and FTD. In AD, EEG slowing was associated with cognitive impairment, while in DLB, this was associated with higher DLB characteristics. In the ROC analyses to distinguish DLB from FTD and AD, measures of EEG slowing yielded high area under curve values, with good specificities. Also, decreased alpha reactivity could distinguish DLB from FTD with good specificity. EEG slowing in DLB showed a diffuse pattern compared to AD, where a posterior and temporal slowing predominated. CONCLUSION: We showed that EEG slowing was satisfactory in distinguishing DLB patients from AD and FTD patients. Notably, this slowing was a characteristic finding in DLB patients, even at early stages, while it paralleled disease progression in AD. Furthermore, EEG slowing in DLB showed a diffuse pattern compared to AD, where a posterior and temporal slowing predominated. These findings align with the previous evidence of the diencephalic dysfunction in DLB.
Assuntos
Doença de Alzheimer , Eletroencefalografia , Demência Frontotemporal , Doença por Corpos de Lewy , Humanos , Feminino , Masculino , Eletroencefalografia/métodos , Diagnóstico Diferencial , Idoso , Doença por Corpos de Lewy/diagnóstico , Doença por Corpos de Lewy/fisiopatologia , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/fisiopatologia , Demência Frontotemporal/diagnóstico , Demência Frontotemporal/fisiopatologia , Pessoa de Meia-Idade , Idoso de 80 Anos ou maisRESUMO
BACKGROUND: Here, we aimed to investigate the roles of long-term potentiation-like (LTP-like) plasticity using intermittent theta burst (iTBS) protocol and resting motor threshold (rMT) in the differential diagnosis of Alzheimer's disease (AD), diffuse dementia with Lewy bodies (DLB) and frontotemporal dementia (FTD). METHOD: We enrolled 21 subjects with AD, 28 subjects with DLB, 14 subjects with FTD, and 33 elderly subjects with normal cognitive functions into the study. We recorded rMT and percentage amplitude change of motor evoked potentials (MEPs) after the iTBS protocol in each group. RESULTS: In patients with AD and DLB, the percentage amplitude change of MEPs, and rMTs were significantly lower than in healthy subjects. However, no significant difference was observed in individuals with FTD. CONCLUSION: Our findings showed that transcranial magnetic stimulation measures, particularly rMTs and LTP-like plasticity, may be potential biomarkers to distinguish between different dementia subtypes. Impaired motor cortical excitability and synaptic plasticity were more prominent in AD and DLB than in FTD. This aligns with the evidence that cortical motor networks are usually spared in FTDs in early-to-middle stages.
Assuntos
Doença de Alzheimer , Excitabilidade Cortical , Demência Frontotemporal , Doença por Corpos de Lewy , Doença de Pick , Idoso , Humanos , Demência Frontotemporal/diagnóstico , Doença de Alzheimer/diagnóstico , Doença por Corpos de Lewy/diagnóstico , Estimulação Magnética TranscranianaRESUMO
BACKGROUND: Dementia encompasses a range of neurodegenerative disorders characterized by cognitive decline and functional impairment. The identification of reliable biomarkers is essential for accurate diagnosis and gaining insights into the mechanisms underlying diseases. OBJECTIVE: This study aimed to investigate the plasma biomarker profiles associated with Brain- Derived Neurotrophic Factor (BDNF), Oxytocin, Neuronal Pentraxin-1 (NPTX1), Triggering Receptor Expressed on Myeloid Cells 2 (TREM2), Tumor Necrosis Factor-alpha (TNF-alpha), Interleukin- 1 (IL-1), and Prolactin in Alzheimer's disease (AD), dementia with Lewy bodies (DLB), frontotemporal dementias (FTD), and healthy controls. METHODS: Serum levels of the aforementioned biomarkers were analyzed in 23 AD, 28 DLB, 15 FTD patients recruited from outpatient units, and 22 healthy controls. Diagnostic evaluations followed established criteria, and standardized clinical tests were conducted. Blood samples were collected and analyzed using ELISA and electrochemiluminescence immunoassay methods. RESULTS: Serum BDNF and oxytocin levels did not significantly differ across groups. NPTX1, TREM2, TNF-alpha, and IL-1 levels also did not show significant differences among dementia groups. However, prolactin levels exhibited distinct patterns, with lower levels in male DLB patients and higher levels in female AD patients compared to controls. CONCLUSION: The study findings suggest potential shared mechanisms in dementia pathophysiology and highlight the importance of exploring neuroendocrine responses, particularly in AD and DLB. However, further research is warranted to elucidate the role of these biomarkers in dementia diagnosis and disease progression.
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We investigated the psychiatric symptomatology and the protracted symptoms in patients who had recovered from the acute COVID-19 infection. Two hundred and eighty-four patients completed a web-based or a paper survey on socio-demographic and clinical data. The psychiatric status was assessed using Impact of Events Scale-Revised (IES-R), Hospital Anxiety and Depression Scale (HADS), Pittsburgh Sleep Quality Index (PSQI), and MINI suicidality scale. Patients completed a checklist for the protracted symptoms that were experienced after the acute infection. After a mean of almost 50 days following the diagnosis, 98 patients (34.5%) reported clinically significant PTSD, anxiety, and/or depression, with PTSD being the most common condition reported (25.4%). One hundred and eighteen patients (44.3%) reported one or more protracted symptom(s). Predictors of PTSD symptom severity were the female gender, past traumatic events, protracted symptoms, stigmatization, and a negative view on the COVID-19 pandemic. PTSD symptom severity was the sole independent predictor of the protracted symptoms. Our results suggest that COVID-19 patients are prone to substantial psychological distress in the first few months after the infection. The protracted symptoms were frequent in this period, and these were closely related to the posttraumatic symptoms.