(a) To characterize the frequency of objective cognitive deficits and self-perceived cognitive difficulties and (b) to explore demographic and clinical predictors of cognitive dysfunction and cognitive complaints. One hundred and ten adults diagnosed with COVID-19 between March and November 2020, aged ≤ 74 years underwent a brief neuropsychological evaluation 12 months after infection, which included: Brief Visuospatial Memory Test-Revised, California Verbal Learning Test, and Symbol Digit Modalities Test. T scores < 38 were considered abnormal performance; cognitive dysfunction was defined as ≥ 2 abnormal tests. Participants also completed Broadbent's Cognitive Failure Questionnaires (CFQ), Hospital Anxiety and Depression Scale, Modified Fatigue Impact Scale, and Short-Form Health Survey. CFQ ≥ 43 was considered indicative of cognitive complaints. Twenty participants (18.2%) had cognitive dysfunction and 36 (33.3%) had cognitive complaints. Cognitive dysfunction was related to lower education, preinfection history of headache/migraine, and acute COVID-19 symptoms of headache and sleep disturbance. Cognitive complaints were more likely to occur in women, those with fewer years of education, and acute COVID-19 symptoms of headache and sleep disturbance. Cognitive complaints were also significantly related to symptoms of anxiety, depression, and fatigue. Sex and psychopathology were not significant predictors of cognitive dysfunction. Modest associations were found between CFQ total score and cognitive test performance. A subset of individuals develops cognitive difficulties in the context of post-COVID syndrome. Results may support the protective effect of education, a known proxy of cognitive reserve. COVID-19 infection symptoms of headache and sleep disturbance appear to be risk factors for long-term cognitive difficulties. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Background: Stiff Person Spectrum Disorders (SPSD) are classically defined by the presence of muscle stiffness, spasms and hyperactivity of the central nervous system. There is a notable correlation between neurophysiological features and the clinical hallmark of SPSD, which has greatly encouraged the use of these techniques for diagnostic purposes. Besides, electrophysiological techniques allow for a functional evaluation of the ‘hyperactivity of the CNS’, thus offering the opportunity to clarify the mechanisms underlying this disorder. This review delves into the current knowledge on the electrophysiological aspects of SPSD, highlighting the pivotal role of various studies in unravelling its pathophysiology.Methods: Literature review for studies on SPSD that included a neurophysiological evaluation.Results: We first examined the abnormal neurophysiological findings of SPSD across the central nervous system, from the spinal circuit to the motor cortex. Subsequently, we discussed their pathological implications and explored how these findings can be interpreted within the framework of an immune‐mediated disorder.Conclusions: Two primary questions remain unanswered: the localization of the primary abnormality within the central nervous system and the connection between the autoimmune basis of SPSD and its neurophysiological aspects. Addressing these questions could provide invaluable insights into SPSD etiology and targeted therapeutic strategies.

Introduction: Anti-GAD65 antibodies are associated with several neurological phenotypes. Antibody titers are increasingly recognized as useful in diagnosis and prognosis. Objective: To describe a Portuguese cohort of patients with anti-GAD65-associated neurological syndromes. Methods: Retrospective analysis of all patients with positive anti-GAD65 antibodies and associated neurological syndromes followed in a tertiary referral center. Results: Nineteen anti-GAD65 antibody-positive neurological patients were identified, 62.3% female, with a mean age of onset of 56.0 (SD = 13.3) years. Comorbid autoimmune disorders were present in seven patients. Six patients had limbic encephalitis (31.6%), four had epilepsy (21.1%), four had cerebellar ataxia (21.1%), and three had stiff-person syndrome (15.8%). Two patients presented with isolated cognitive dysfunction (executive and mnesic) in the absence of other neurological symptoms. The mean follow-up time was 24.0 (14.0–42.0) months, at the end of which the mean modified Rankin Scale (mRS) value was 2.0 (1.0–4.0). Screening for malignancies was negative in all patients. Serum quantitative analysis was carried out in 18 patients, 10 of whom showed titers above previously defined cut-off points (>10,000 IU/L for ELISA and >20 mmol/L for RIA). Quantitative CSF analysis was performed in nine patients, with four showing above-threshold titers. There was no association between anti-GAD65 levels and clinical phenotype or the final mRS values. High-dose intravenous methylprednisolone and oral prednisolone were the most common acute and chronic treatment regimens, respectively. Conclusion: Anti-GAD65 antibodies are associated with varied neurological syndromes, and antibody titers alone should not be used to exclude a disease.

Introduction: Early-onset (EOMG) and late-onset (LOMG) are distinct groups of MG patients. It is unclear if treatment strategies and treatment-related adverse events may differ according to the age of MG onset.Methods: This single-center retrospective study includes all MG patients followed at a tertiary center since 2007. We reviewed the electronic clinical records.Results: In total, 212 patients were identified, 142 (67.0%) females, with a median disease duration of 10 years. The median age of symptom onset was 42.0 (26.0–64.5) years, with 130 (61.3%) EOMG cases and 82 (38.7%) LOMG. EOMG were more frequently female, had longer disease duration and often more generalized MG (p < 0.001). Comorbidities were significantly more frequent in LOMG (67.1%) compared to EOMG (53.1%) (p = 0.002). Steroid-related adverse effects motivating the switch to steroid-sparing agents (82.0%) were different between groups, with hypertension, hypercholesterolemia, diabetes mellitus and malignancies being more common in LOMG. At the same time, osteoporosis and dyspepsia were more frequent in EOMG (p < 0.001). The most common first-line choice was azathioprine (45.8%), and rituximab was used in 4 patients (1.9%).Conclusion: Our study shows that treatment modalities are similar between EOMG and LOMG, while steroid-related adverse events appear to be distinct.