Guillain‐Barre syndrome following COVID‐19 vaccines (GBSfCV19v) is a reported adverse effect that remains unclear. We present a structured review based on two case reports of GBSfCV19v, a systematic review, and Vaccine Adverse Event Reporting System (VAERS) analysis to estimate the risk and describe the clinical characteristics (CC) of these events. We've searched on MEDLINE and Embase, from the inception to May 20, 2021, using the keywords: “Guillain barre syndrome” and cross‐referenced with “covid‐19 vaccines.” We estimated the risk of GBSfCV19v, comparing it with the risk of GBS following the influenza vaccine (GBSfIv), considering the VAERS sensitivity. The clinical characteristics included: age, sex, comorbidities, type of vaccine, administered dose, clinical onset, deaths, cerebrospinal fluid (CSF), and electromyography (EMG) pattern. We found 43 cases, considering the risk of GBSfCV19v lower than GBSfIv (160–320 cases). The patients had a mean age of 54 years and 23 (56%) were male. The types of vaccines used: Pfizer (22), Moderna (9), AstraZeneca (3), Janssen (3), and Johnson & Johnson (1). 24 cases of GBS occurred after the first dose, with clinical onset of 7 days. CSF albuminocytological dissociation was reported in 7 patients, and EMG revealed a predominant demyelinating pattern. GBSfCV19v risk appears to be lower than what was expected from other respiratory virus vaccines. Most cases of GBS were middle‐aged males within a week following the first dose of the COVID‐19 vaccine, showing a typical demyelinating neuropathy with albuminocytological dissociation.

Background: For the last 20 years, the amyloid-beta (Aβ) cascade hypothesis has been dominant in the research of disease-modifying therapeutics, with spent of financial and clinical resources in potential drugs targeting Aβ peptide production or clearance. (1) In this context, monoclonal antibodies targeting beta-amyloid (Aβ-mAbs) are being tested to reduce the amyloid burden in patients with Alzheimer's Disease (AD). (2) However, the cognitive impact of Aβ-mAbs remains controversial. (3) We aim to evaluate the conflicting results of previous studies using a meta-analysis. Method: We searched PubMed, Embase, and Cochrane databases, following until April 2021, using the search terms: ''Alzheimer's disease'' OR ''dementia'' cross-referenced with ''monoclonal antibodies'' , considering the synonyms. Eligible articles were randomized clinical trials with Aβ-mAbs that reported cognitive outcomes. The cognitive function was assessed by Alzheimer's Disease Assessment Scale (ADAS-cog) and Mini-Mental State-Exam (MMSE). We performed a meta-analysis comparing mAbs and placebo, considering a minimal significant clinical change of 3 points in ADAS-Cog and 2 points in MMSE. Result: We found 12 eligible studies in 443 identified records, involving 6736 patients, mean age 71.4 ± 2. We found a small benefit in cognitive outcomes in patients treated with Aβ-mAbs: ADAS-Cog: mean difference (MD) = -0.65; 95% CI (-1.05 to -0.26); Iš = 12%; (p = 0.001) and MMSE: MD = 0.40; 95% CI (0.18 to 0.63); Iš = 10%; (p = 0.0004). The Funnel plot and Egger's test did not show publication bias. MD was below the minimal clinically relevant change in both scales. Conclusion:Aβ-mAbs may have a positive cognitive benefit in AD patients. However, the impact magnitude is small, not reaching minimal clinically relevant change for these scales. References: (1)

Objective: to verify if the prevalence of dementia differs between widowed and non-widowed elderly persons and between genders, and to analyse if there is an association with sociodemographic and clinical characteristics. Method: a retrospective cross-sectional observational study of patients treated at a Behavioral Neurology outpatient clinic from 1999 to 2009 was carried out, employing anamnesis, physical and neurological examination, the Clinical Dementia Rating Scale (CDR) and the Mini Mental State Examination (MMSE). Sociodemographic (schooling and age) and clinical (age of onset of symptoms and time since onset of symptoms, MMSE and CDR) variables were analyzed. The differences were evaluated by the Mann Whitney test, using a significance value of p<0.05. Results: of 208 patients diagnosed with dementia, 73 (35.1%) were widowed and 135 (64.9%) were non-widowed. Those who were widowed were older than those who were non-widowed (p<0.001) when diagnosed with dementia. This difference in age remained when gender (p<0.001), widowed and widowed women (p<0.001) and widowed and non-widowed men (p<0.001) were compared. The time from onset of symptoms to diagnosis was greater in widowed than in non-widowed men [55.6 (± 86.3) vs. 43.4 (± 44.8) months], although the difference was not statistically significant. Widowed patients with dementia had lower schooling, regardless of gender (p<0.05). Conclusion: the prevalence of dementia differed between widowed and non-widowed individuals, being higher among non-widows. There was an association between widowhood and the clinical and sociodemographic characteristics, with differences between the genders. The loss of a spouse can generate different outcomes among men and women, necessitating measures with a specific focus on prevention and strategies of care in dementia.