Acute and post-acute neurological manifestations of COVID-19: present findings, critical appraisal, and future directions

Brain organoids: building higher-order complexity and neural circuitry models

Brain organoids are 3D tissue models of the human brain that are derived from pluripotent stem cells (PSCs). They have enabled studies that were previously stymied by the inaccessibility of human brain tissue or the limitations of mouse models of some brain diseases. Despite their enormous potential, brain organoids have had significant limitations that prevented them from recapitulating the full complexity of the human brain and reduced their utility in disease studies. We describe recent progress in addressing these limitations, especially building complex organoids that recapitulate the interactions between multiple brain regions, and reconstructing in vitro the neural circuitry present in in vivo. These major advances in the human brain organoid technology will remarkably facilitate brain disease modeling and neuroscience research.

Neuroinflammation in Severe COVID-19: The Dynamics of Inflammatory and Brain Injury Markers During Hospitalization

Patients with COVID-19 can develop excessive inflammation in the brain and consequent neurological complications. The aim of this study was to evaluate the inflammatory, endothelial and brain injury markers in hospitalized COVID-19 patients and compare those with or without neurological symptoms. A total of 30 intensive care unit (ICU) COVID-19 patients were allocated into COVID-19 (without neurological symptoms) or neuro-COVID-19 (with neurological symptoms) groups. Patients with respiratory infection symptoms but negative for COVID-19 were included as a control group. Peripheral blood samples were collected at hospital admission (T1) (controls and ICU patients) and during hospitalization (T2: last 72 h before hospital discharge or in-hospital death) (ICU COVID-19 patients) to analyze inflammatory markers. Higher ICAM-1, CCL26 and VEGF at T1 were identified in both COVID-19 groups compared with control. Neuro-COVID-19 patients presented lower systemic BDNF levels compared with the control group and increased S100B compared with the control and COVID-19 groups. BDNF levels in survivors were lower in the neuro-COVID-19 group compared to the COVID-19 group, while S100B were higher, regardless of the outcome. In addition, all COVID-19 patients presented increased ICAM-1 and CCL26 levels over the hospitalization period (T2 > T1). Furthermore, S100B, ICAM-1, CCL26 and VEGF levels increased in relation to T1 in neuro-COVID-19 patients, with S100B and CCL26 being significantly higher in relation to the COVID-19 group. In conclusion, high levels of brain injury biomarkers were found in patients with neuro-COVID-19, indicating neuroinflammatory and consequent brain injury in the last 72 h of hospitalization.

Impact of COVID-19 on functional, cognitive, neuropsychiatric, and health-related outcomes in patients with dementia: A systematic review

Background

This systematic review analyzes the impact of COVID-19 on dementia patients' functional, cognitive, neuropsychiatric, and health related outcomes. It hypothesizes that dementia patients infected with SARS-CoV-2experience more pronounced deterioration compared to those who are uninfected.

Methods

Research from 01/03/2020 to 07/10/2023 was conducted using Medline, Web of Science, and Embase databases, and adhering to PRISMA guidelines and the PICO framework. The study aimed to determine if SARS-CoV-2 infection is associated with worse outcomes in dementia patients. The protocol is registered in PROSPERO (CRD42022352481), and bias was evaluated using the Newcastle-Ottawa Scale.

Results

Among 198 studies reviewed, only three met the criteria. Chen et al. (2023) identified higher mortality in SARS-CoV-2-infected dementia patients, while Merla et al. (2023) observed faster cognitive decline in infected individuals with increased hospital admissions. Additionally, Cascini et al. (2022) reported an increased risk of infection and significantly elevated mortality in dementia patients, highlighting comorbidities and antipsychotic medication use as key risk factors.

Conclusion

These limited data suggest higher mortality and cognitive decline in dementia patients following COVID-19, underscoring the need for extensive research in this area.

Immunologic and inflammatory consequences of SARS-CoV-2 infection and its implications in renal disease

The emergence of the COVID-19 pandemic made it critical to understand the immune and inflammatory responses to the SARS-CoV-2 virus. It became increasingly recognized that the immune response was a key mediator of illness severity and that its mechanisms needed to be better understood. Early infection of both tissue and immune cells, such as macrophages, leading to pyroptosis-mediated inflammasome production in an organ system critical for systemic oxygenation likely plays a central role in the morbidity wrought by SARS-CoV-2. Delayed transcription of Type I and Type III interferons by SARS-CoV-2 may lead to early disinhibition of viral replication. Cytokines such as interleukin-1 (IL-1), IL-6, IL-12, and tumor necrosis factor α (TNFα), some of which may be produced through mechanisms involving nuclear factor kappa B (NF-κB), likely contribute to the hyperinflammatory state in patients with severe COVID-19. Lymphopenia, more apparent among natural killer (NK) cells, CD8+ T-cells, and B-cells, can contribute to disease severity and may reflect direct cytopathic effects of SARS-CoV-2 or end-organ sequestration. Direct infection and immune activation of endothelial cells by SARS-CoV-2 may be a critical mechanism through which end-organ systems are impacted. In this context, endovascular neutrophil extracellular trap (NET) formation and microthrombi development can be seen in the lungs and other critical organs throughout the body, such as the heart, gut, and brain. The kidney may be among the most impacted extrapulmonary organ by SARS-CoV-2 infection owing to a high concentration of ACE2 and exposure to systemic SARS-CoV-2. In the kidney, acute tubular injury, early myofibroblast activation, and collapsing glomerulopathy in select populations likely account for COVID-19-related AKI and CKD development. The development of COVID-19-associated nephropathy (COVAN), in particular, may be mediated through IL-6 and signal transducer and activator of transcription 3 (STAT3) signaling, suggesting a direct connection between the COVID-19-related immune response and the development of chronic disease. Chronic manifestations of COVID-19 also include systemic conditions like Multisystem Inflammatory Syndrome in Children (MIS-C) and Adults (MIS-A) and post-acute sequelae of COVID-19 (PASC), which may reflect a spectrum of clinical presentations of persistent immune dysregulation. The lessons learned and those undergoing continued study likely have broad implications for understanding viral infections' immunologic and inflammatory consequences beyond coronaviruses.

Patients with neurological or psychiatric complications of COVID-19 have worse long-term functional outcomes: COVID-CNS-A multicentre case-control study

It is established that patients hospitalised with COVID-19 often have ongoing morbidity affecting activity of daily living (ADL), employment, and mental health. However, little is known about the relative outcomes in patients with COVID-19 neurological or psychiatric complications. We conducted a UK multicentre case-control study of patients hospitalised with COVID-19 (controls) and those who developed COVID-19 associated acute neurological or psychiatric complications (cases). Among the 651 patients, [362 (55%) cases and 289 (45%) controls], a higher proportion of cases had impairment in ADLs (199 [68.9%] vs 101 [51.8%], OR 2.06, p < 0.0002) and reported symptoms impacting employment (159 [58.2%] vs 69 [35.6%] OR 2.53, p < 0.0001). There was no significant difference in the proportion with depression or anxiety between case and control groups overall. For cases, impairment of ADLs was associated with increased risk in female sex, age > 50 years and hypertension (OR 5.43, p < 0.003, 3.11, p = 0.02, 3.66, p = 0.04). Those receiving either statins or angiotensin converting enzyme (ACE) inhibitors had a lower risk of impairment in ADLs (OR 0.09, p = 0.0006, 0.17, p = 0.03). Patients with neurological or psychiatric complications of COVID-19 had worse functional outcomes than those with respiratory COVID-19 alone in terms of ADLs and employment. Female sex, age > 50 years, and hypertension were associated with worse outcomes, and statins or ACE inhibitors with better outcomes.

Diagnostic Models for Differentiating COVID-19-Related Acute Ischemic Stroke Using Machine Learning Methods

Backgrounds: Although COVID-19 is primarily known as a respiratory disease, there is growing evidence of neurological complications, such as ischemic stroke, in infected individuals. This study aims to evaluate the impact of COVID-19 on acute ischemic stroke (AIS) using radiomic features extracted from brain MR images and machine learning methods. Methods: This retrospective study included MRI data from 57 patients diagnosed with AIS who presented to the Department of Radiology at Hacettepe University Hospital between March 2020 and September 2021. Patients were stratified into COVID-19-positive (n = 30) and COVID-19-negative (n = 27) groups based on PCR results. Radiomic features were extracted from brain MR images following image processing steps. Various feature selection algorithms were applied to identify the most relevant features, which were then used to train and evaluate machine learning classification models. Model performance was evaluated using a range of classification metrics, including measures of predictive accuracy and diagnostic reliability, with 95% confidence intervals provided to enhance reliability. Results: This study assessed the performance of dimensionality reduction and classification algorithms in distinguishing COVID-19-negative and COVID-19-positive cases using radiomics data from brain MR scans. Without feature selection, ANN achieved the highest AUC of 0.857 (95% CI: 0.806-0.900), demonstrating strong discriminative power. Using the Boruta method for feature selection, the k-NN classifier attained the best performance, with an AUC of 0.863 (95% CI: 0.816-0.904). LASSO-based feature selection showed comparable results across k-NN, RF, and ANN classifiers, while SVM exhibited excellent specificity and high PPV. The RFE method yielded the highest overall performance, with the k-NN classifier achieving an AUC of 0.882 (95% CI: 0.838-0.924) and an accuracy of 79.1% (95% CI: 73.6-83.8). Among the methods, RFE provided the most consistent results, with k-NN and the ANN identified as the most effective classifiers for COVID-19 detection. Conclusions: The proposed radiomics-based classification model effectively distinguishes AIS associated with COVID-19 from brain MRI. These findings demonstrate the potential of AI-driven diagnostic tools to identify high-risk patients, support optimized treatment strategies, and ultimately improve clinical implications.

Impact of SARS-CoV-2 Infection on Essential Tremor: A Retrospective Clinical and Kinematic Analysis

In the past few years, SARS-CoV-2 infection has substantially impacted public health. Alongside respiratory symptoms, some individuals have reported new neurological manifestations or a worsening of pre-existing neurological conditions. We previously documented two cases of essential tremor (ET) who experienced a deterioration in tremor following SARS-CoV-2 infection. However, the effects of SARS-CoV-2 on ET remain largely unexplored. This study aims to evaluate the impact of SARS-CoV-2 infection on a relatively broad sample of ET patients by retrospectively comparing their clinical and kinematic data collected before and after the exposure to SARS-CoV-2. We surveyed to evaluate the impact of SARS-CoV-2 infection on tremor features in ET. Subsequently, we retrospectively analysed clinical and kinematic data, including accelerometric recordings of postural and kinetic tremor. We included 36 ET patients (14 females with a mean age of 71.1 ± 10.6 years). Among the 25 patients who reported SARS-CoV-2 infection, 11 (44%) noted a subjective worsening of tremor. All patients reporting subjective tremor worsening also exhibited symptoms of long COVID, whereas the prevalence of these symptoms was lower (50%) in those without subjective exacerbation. The retrospective analysis of clinical data revealed a tremor deterioration in infected patients, which was not observed in non-infected patients. Finally, kinematic analysis revealed substantial stability of tremor features in both groups. The study highlighted a potential correlation between the SARS-CoV-2 infection and clinical worsening of ET. Long COVID contributes to a greater impact of tremor on the daily life of ET patients.

Headache severity in patients with post COVID-19 condition: a case-control study

Post COVID-19 conditions (PCC) present with a wide range of symptoms. Headache is one of the most frequently reported neurological symptoms by patients with PCC. We aimed to assess the prevalence of headache in patients with PCC who attended the Post-COVIDLMU outpatient department at LMU University Hospital in Munich. We hypothesized that headaches occur more frequently in patients with PCC than in the control group. Patients answered a questionnaire containing sociodemographic characteristics, their current symptoms, and prior psychiatric and somatic diagnoses, the WHO Quality of Life assessment (WHOQOL-BREF), 9-item Patient Health Questionnaire (PHQ-9), and the Fatigue Severity Scale (FSS). 188 PCC patients were included in this study and compared to a control group of patients with a history of COVID-19 or a different infectious disease - but no consecutive post-infectious condition (nc=27). 115 (61%) of our PCC patients were female. The median age was 41 years. 60 (32%, p = 0.001) had a pre-existing psychiatric diagnosis. PCC was associated with worse outcomes in all four domains of the WHOQOL-BREF (p < 0.001), high levels of fatigue (FSS; p < 0.001), and a higher likeliness for symptoms of depression (PHQ-9; p < 0.001). We were able to confirm that psychiatric disorders are more frequently associated with headaches in PCC patients. Headache should be assessed and treated in the context of PCC not only by neurologists but by multi-professional teams and regarding all PCC symptoms.

Sex Differences in Long-Term Cardiovascular Outcomes and Mortality After COVID-19 Hospitalization During Alpha, Delta and Omicron Waves

Background: Increased mortality and occurrence of cardiovascular (CV) outcomes during hospitalization and in short-term follow-up for moderate to severe SARS-CoV-2 infection have been associated with male sex, yet data regarding long-term outcomes by sex and COVID-19 variant (Alpha, Delta, and Omicron) are limited. Methods: This prospective study of 4882 patients examines potential differences by sex in the occurrence of primary combined cardiovascular outcomes (CV death, CV hospitalization, myocardial infarction (MI), stroke, pulmonary embolism) as well as secondary outcomes (CV death, cardiovascular hospitalizations, myocardial infarction, stroke, pulmonary embolism) at 18-month follow-up after urgent hospitalization for SARS-CoV-2-associated pneumonia, as well as evaluating for differences during the three COVID-19 waves. Survival rate was analyzed for the entire cohort by sex and SARS-CoV-2 variant and adjusted for age using the multiple Kaplan-Meier method. To compare survival in groups of men and women for each wave, the Gehan-Wilcoxon test was applied with significance p < 0.05. Univariate Cox proportional hazards models were used to search for potential risk factors of CV death at 18-months follow-up separately for men and women in each COVID-19 wave. Results: Men had significantly higher 18-month CV mortality compared to women in the Delta wave (6.13% men vs. 3.62% women, p = 0.017). Although men had higher percentages of all other CV endpoints (excepting pulmonary embolism) at follow-up during the Delta wave, none were significant compared with women, except for the combined CV endpoint (16.87% men vs. 12.61% women, p = 0.017). No significant differences by sex in CV outcomes were seen during the Alpha and Omicron variants. Discrepancies in CV outcomes in demographical data and concomitant disease between the COVID-19 variants of concern existed. Conclusions: Higher male mortality and higher but non-significant incidences of CV outcomes occurred during the Delta wave of the COVID-19 pandemic, with the lowest incidence of CV outcomes observed during the Omicron variant.

Impact on the nervous system of long COVID-19 infection in children

BACKGROUND

 The coronavirus disease 2019 (COVID-19) pandemic has had a profound global impact, raising concerns about its long-term effects, particularly neurological complications. While studies have highlighted such complications in adults, there is a paucity of research focusing on children.

OBJECTIVE

 To examine the medium- to long-term neurological and cognitive symptoms in 18 year old children and below with positive versus negative COVID-19 antigens and to identify the probable risk factors to promote specific health actions.

METHODS

 An observational study was carried out to determine neurological symptoms in the medium and long terms after COVID 19. A random sample of 124 children, both symptomatic or asymptomatic, tested positive or negative for COVID-19 through swab tests.

RESULTS

 Neurological symptoms were assessed between 6 to 12 months and 2 years after the infection. Acute symptoms, including headache, anosmia, ageusia, and myalgia, were observed in more than 20% of the children, but they generally resolved within 6 to 12 months. Persistent functional difficulties, such as in studying, paying attention, and socializing, were reported in 3% of the cases. Behavioral symptoms at baseline were noted in 7.8% of children, but they were remitted in most cases, except for those with prior involvement.

CONCLUSION

 These findings underscore the need for continued monitoring of children following COVID-19 infection and the importance of tailored health interventions.

Impact of the COVID-19 pandemic on risk of sarcopenia: From lockdown and infection perspectives: A systematic review and meta-analysis

BACKGROUND

During the new coronavirus disease 2019 (COVID-19) pandemic, there are numerous symptoms in the skeletal muscular system, such as decreased skeletal muscle mass, strength, and muscle function, which are the main manifestations of sarcopenia. To investigate the impact of the COVID-19 pandemic on sarcopenia from the perspectives of COVID-19 pandemic lockdown and COVID-19 infection, we conducted this study.

METHODS

We searched for literature related to COVID-19 and sarcopenia published in PubMed, Embase, Cochrane Library, and Web of Science. Two researchers independently searched and screened the articles, extracted data, and assessed the quality of the final included literature. RevMan 5.4 was used for meta-analysis.

RESULTS

A total of 8 articles with a total of 1145 patients were included. There was a significant difference in SARC-F scores (MD = 0.67, 95%CI = [0.41, 0.93], Z = 5.00, P < .00001), handgrip (MD = -1.57, 95%CI = [-2.41, -0.73], Z = 3.66, P = .0002), body weight (MD = -1.87, 95%CI = [-3.69, -0.05], Z = 2.01, P = .04), and skeletal muscle mass index (MD = -0.28, 95%CI = [-0.54, -0.02], Z = 2.13, P = .03) between the time before the COVID-19 pandemic and during the COVID-19 pandemic. However, the results showed that there was no significant difference in muscle mass between the 2 groups (MD = -1.72, 95%CI = [-4.39, 0.94], Z = 1.27, P = .21).

CONCLUSION

The COVID-19 pandemic has had an impact on sarcopenia. Both infection with COVID-19 and lockdown during the COVID-19 pandemic increase the risk of sarcopenia. Research should pay more attention to this disease during the COVID-19 pandemic and adopt effective interventions to minimize adverse outcomes.

Acute and Preventive Treatment of COVID-19-Related Headache: A Series of 100 Patients

To describe the need and effectiveness of acute and preventive medications in a series of 100 consecutive patients referred due to COVID-19-related headaches. Patients were aged 48.0 (standard deviation (SD): 12.4), 84% were female, and 56% had a prior history of headache. The most common headache phenotype was holocranial (63%), frontal (48%), pressing (75%), of moderate intensity (7 out of 10), and accompanied by photophobia (58%). Acute medication was required by 93%, with paracetamol (46%) being the most frequently used drug, followed by ibuprofen (44%). The drugs with the highest proportion of a 2 h pain-freedom response were dexketoprofen (58.8%), triptans (57.7%), and ibuprofen (54.3%). Preventive treatment was required by 75% of patients. The most frequently used drugs were amitriptyline (66%), anesthetic blockades (18%), and onabotulinumtoxinA (11%). The drugs with the highest 50% responder rate were amitriptyline (45.5%), mirtazapine (50%), and anesthetic blockades (38.9%). The highest 75% responder rate was experienced following onabotulinumtoxinA (18.2%). In conclusion, most patients required acute medication, with triptans and non-steroidal anti-inflammatory drugs achieving the best responses. Three-quarters of patients required preventive medication. The most frequently used drug was amitriptyline, which obtained the best results. In some treatment-resistant patients, anesthetic blockades and onabotulinumtoxinA were also beneficial.

Neuropsychological functioning and its correlates at 1 year follow-up of severe COVID-19

BACKGROUND

Short-term cognitive impairment is associated with SARS-CoV-2 infection but the long-term impact is yet to be examined in detail. We aim to study the evolution of these symptoms in severe COVID-19 patients admitted to the intensive care unit (ICU) between April and December 2020 1 year after hospital discharge and to analyze its clinical correlates.

METHOD

A total of 58 patients agreed to participate in the 6 months follow-up and 30 at 1 year after hospital discharge. Demographic, clinical and laboratory data were collected and a comprehensive neuropsychological battery including validated tests for the main cognitive domains was administered. To test the magnitude of neurocognitive sequelae, two standard deviations below normative group were considered. To compare the neuropsychological performance at 6 and 12 months follow-up we used repeated measures tests. Finally, regression analyses were performed to test the main effects of medical and psychological factors on multiple cognition.

RESULTS

Almost half of the sample continued to have impaired performance on neuropsychological tests at 12 months follow-up. In comparison with the results obtained at 6 months, significant improvements were found in immediate recall (d = 0.49), delayed recall (d = 0.45), and inhibitory control (d = 0.53). Medical variables predicted cognitive performance at 6 months but not at 12 months follow-up, while anxiety and depression predicted cognitive deficits in the long-term.

CONCLUSIONS

A generalised improvement was observed in severe COVID-19 patients at follow-up. This improvement was particularly notable in verbal memory and executive functioning. However, a considerable proportion of the sample continued to present deficits at 1 year follow-up.

Relative frequencies and clinical features of Guillain-Barré Syndrome before and during the COVID-19 pandemic in North China

OBJECTIVE

Most studies investigated the relationship between COVID-19 and Guillain-Barré syndrome (GBS) by comparing the incidence of GBS before and during the pandemic of COVID-19. However, the findings were inconsistent, probably owing to varying degrees of the lockdown policy. The quarantine requirements and travel restrictions in China were lifted around December 7, 2022. This study aimed to explore whether the relative frequency of GBS increased during the major outbreak in the absence of COVID-19-mandated social restrictions in China.

METHODS

GBS patients admitted to the First Hospital, Shanxi Medical University, from December 7, 2022 to February 20, 2023, and from June, 2017 to August, 2019 were included. The relative frequencies of GBS in hospitalized patients during different periods were compared. The patients with and without SARS-CoV-2 infection within six weeks prior to GBS onset formed the COVID-GBS group and non-COVID-GBS group, respectively.

RESULTS

The relative frequency of GBS among hospitalized patients during the major outbreak of COVID-19 (13/14,408) was significantly higher than that before the COVID-19 epidemic (29/160,669, P < 0.001). More COVID-GBS patients (11/13) presented AIDP subtype than non-COVID-GBS cases (10/27, P = 0.003). The mean interval between onset of infective symptoms and GBS was longer in COVID-GBS (21.54 ± 11.56 days) than in non-COVID-GBS (5.76 ± 3.18 days, P < 0.001).

CONCLUSIONS

COVID-19 significantly increased the incidence of GBS. Most COVID-GBS patients fell into the category of AIDP, responded well to IVIg, and had a favorable prognosis.

Neurological manifestations and complications of COVID-19 in patients admitted to a tertiary care center in Nepal during the second wave

Neurological symptoms and signs of Coronavirus disease-19 (COVID-19) can accompany, follow, or precede respiratory symptoms and signs; hence, they are important in the diagnosis and management of COVID-19 patients. In this retrospective study conducted during the second wave of COVID-19, we included all patients diagnosed with COVID-19 using real-time polymerase chain reaction and admitted to the Tribhuvan University Teaching Hospital between June 2021 and October 2021. The patients were categorized into 2 groups: group A (with neurological manifestations or complications) and Group-B (without neurological manifestations or complications). The 2 groups were compared in terms of intensive care unit (ICU) admission, need for ventilatory support, length of hospital stay, and various outcomes. The study included 235 participants ranging in age from 13 to 102 years (mean age = 54 years, standard deviation = 18). Among the participants, 54.50% were male. The proportion of individuals in group A was higher (59.15%, N = 139) than that in Group-B (40.85%, N = 96). Notably, a significantly greater number of patients were admitted to the ICU in Group B than in Group A. However, there were no statistically significant differences in the need for ventilatory support or hospital stay between the 2 groups. Interestingly, group A showed a higher rate of improvement (Z = -3.1145, P = .00188, 95% CI), while Group-B had a higher rate of mortality (Z = 4.5562, P < .00001, 95% CI). Altered mental status and stroke have been specifically linked to poorer outcomes, whereas typical neurological manifestations, such as hyposmia, hypogeusia, dizziness, headache, and myalgia, are associated with better outcomes.

Prevalence and Trajectories of Post-COVID-19 Neurological Manifestations: A Systematic Review and Meta-Analysis

INTRODUCTION

The aim of this systematic review and meta-analysis was to evaluate the prevalence of thirteen neurological manifestations in people affected by COVID-19 during the acute phase and at 3, 6, 9 and 12-month follow-up time points.

METHODS

The study protocol was registered with PROSPERO (CRD42022325505). MEDLINE (PubMed), Embase, and the Cochrane Library were used as information sources. Eligible studies included original articles of cohort studies, case-control studies, cross-sectional studies, and case series with ≥5 subjects that reported the prevalence and type of neurological manifestations, with a minimum follow-up of 3 months after the acute phase of COVID-19 disease. Two independent reviewers screened studies from January 1, 2020, to June 16, 2022. The following manifestations were assessed: neuromuscular disorders, encephalopathy/altered mental status/delirium, movement disorders, dysautonomia, cerebrovascular disorders, cognitive impairment/dementia, sleep disorders, seizures, syncope/transient loss of consciousness, fatigue, gait disturbances, anosmia/hyposmia, and headache. The pooled prevalence and their 95% confidence intervals were calculated at the six pre-specified times.

RESULTS

126 of 6,565 screened studies fulfilled the eligibility criteria, accounting for 1,542,300 subjects with COVID-19 disease. Of these, four studies only reported data on neurological conditions other than the 13 selected. The neurological disorders with the highest pooled prevalence estimates (per 100 subjects) during the acute phase of COVID-19 were anosmia/hyposmia, fatigue, headache, encephalopathy, cognitive impairment, and cerebrovascular disease. At 3-month follow-up, the pooled prevalence of fatigue, cognitive impairment, and sleep disorders was still 20% and higher. At six- and 9-month follow-up, there was a tendency for fatigue, cognitive impairment, sleep disorders, anosmia/hyposmia, and headache to further increase in prevalence. At 12-month follow-up, prevalence estimates decreased but remained high for some disorders, such as fatigue and anosmia/hyposmia. Other neurological disorders had a more fluctuating occurrence.

DISCUSSION

Neurological manifestations were prevalent during the acute phase of COVID-19 and over the 1-year follow-up period, with the highest overall prevalence estimates for fatigue, cognitive impairment, sleep disorders, anosmia/hyposmia, and headache. There was a downward trend over time, suggesting that neurological manifestations in the early post-COVID-19 phase may be long-lasting but not permanent. However, especially for the 12-month follow-up time point, more robust data are needed to confirm this trend.

LIMBIC-CENC: Successfully conducting longitudinal mTBI research during the COVID-19 pandemic

BACKGROUND

Conducting mild traumatic brain injury (mTBI) longitudinal studies across multiple sites is a challenging endeavor which has been made more challenging because of COVID-19.

OBJECTIVE

This article briefly describes several concerns that need to be addressed during the conduct of research to account for COVID-19's impact.

METHODS

The recent actions and steps taken by the Long-term Impact of Military-relevant Brain Injury Consortium (LIMBIC)-Chronic Effects of Neurotrauma Consortium (CENC) researchers are reviewed.

RESULTS

COVID-19's effects on the conduct of LIMBIC-CENC for the short-term and long-term were considered to ensure the study continued safely for participants and researchers. COVID-19 may have long-lasting health and especially neurological effects which may confound the quantitative and qualitative measures of this any comparable longitudinal studies.

CONCLUSION

The recognition, understanding, and preparation of COVID-19's impact on a longitudinal military and veteran mTBI population is crucial to successfully conducting LIMBIC-CENC and similar neurological research studies. Developing a plan based on the best available information while remaining agile as new information about COVID-19 emerge, is essential. Research presented in this special issue underscores the complexity of studying long-term effects of mTBI, in a population exposed to and symptomatic from COVID-19.

The effect of COVID-19 on Multiple Sclerosis relapse: A systematic review and meta-analysis

BACKGROUND

Multiple Sclerosis (MS) is a chronic autoimmune disease, affecting over 2.5 million people worldwide. There has been growing concern about the impact of COVID-19 on the clinical course of MS. However, these findings remain controversial, and there is a lack of high-quality evidence to establish the relationship between COVID-19 and MS.

METHODS

A comprehensive search was done to identify relevant studies reporting relapse rate in patients with MS (pwMS), those comparing the relapse rate of COVID-19 pwMS and MS controls, and studies investigating the effect of COVID-19 on relapse rate of pwMS. The results were presented as proportion of COVID-19 pwMS experiencing relapse and odds ratio determining the impact of COVID-19 on relapse rate.

RESULTS

Fourteen studies were included in the analyses. The proportion of COVID-19 positive pwMS with relapse was 7.71 per 100 cases (95 % confidence interval, CI: 4.41-13.89, I2=96 %). Quantitative evaluation of studies with pwMS without COVID-19 did not demonstrate a statistically significant difference in relapse rate of patients with COVID-19 (OR: 0.75, 95 %CI: 0.44-1.29, I2= 54 %). Subgroup and sensitivity analyses did not alter the lack of significance of association between COVID-19 and MS relapse. Sensitivity analysis excluding the outlying study was largely in favor of no difference between the groups (OR:1.00, 95 %CI: 0.72-1.38, I2=34 %) CONCLUSION: The results of this review does not suggest that COVID-19 influences the relapse rate in pwMS. While the findings alleviate the concerns regarding the co-occurrence of the diseases, further studies are needed to investigate the effects of confounding factors.

Evolving Clinical Manifestations and Outcomes in COVID-19 Patients: A Comparative Analysis of SARS-CoV-2 Variant Waves in a Romanian Hospital Setting

The aim of this study was to evaluate differences in the clinical manifestations and outcomes in hospitalized patients with COVID-19 in a single Romanian center during four pandemic waves determined by different SARS-CoV-2 variants of concern (VOCs). A retrospective study on 9049 consecutive hospitalized adult patients was performed between 27 February 2020 and 31 March 2023. The study interval was divided into waves based on national data on SARS-CoV-2 VOCs' circulation. Multivariate logistic regression models were built, predicting death and complications as functions of comorbidities, therapy, wave, severity form, and vaccination status, and adjusted for ages ≥65 years. Pulmonary (pneumothorax/pneumomediastinum, pulmonary embolism) and extrapulmonary complications (liver injury, acute kidney injury, ischemic/hemorrhagic stroke, myocardial infarction, and gastrointestinal bleeding) were present, more frequently in ICU hospitalized patients and with differences between waves. The highest in-hospital mortality was found in patients presenting pneumothorax/pneumomediastinum. All of the evaluated risk factors were significantly associated with death, except for obesity and the Omicron wave. Our study highlights the changing nature of COVID-19 and acknowledges the impacts of viral mutations on disease outcomes. For all four waves, COVID-19 was a severe disease with a high risk of poor outcomes.

Metabolic and toxicological considerations regarding CGRP mAbs and CGRP antagonists to treat migraine in COVID-19 patients: a narrative review

INTRODUCTION

Migraine pharmacological therapies targeting calcitonin gene-related peptide (CGRP), including monoclonal antibodies and gepants, have shown clinical effect and optimal tolerability. Interactions between treatments of COVID-19 and CGRP-related drugs have not been reviewed.

AREAS COVERED

An overview of CGRP, a description of the characteristics of each CGRP-related drug and its response predictors, COVID-19 and its treatment, the interactions between CGRP-related drugs and COVID-19 treatment, COVID-19 and vaccination-induced headache, and the neurological consequences of Covid-19.

EXPERT OPINION

Clinicians should be careful about using gepants for COVID-19 patients, due to the potential drug interactions with drugs metabolized via CYP3A4 cytochrome. In particular, COVID-19 treatment (especially nirmatrelvir packaged with ritonavir, as Paxlovid) should be considered cautiously. It is advisable to stop or adjust the dose (10 mg atogepant when used for episodic migraine) of gepants when using Paxlovid (except for zavegepant). CGRP moncolconal antibodies (CGRP-mAbs) do not have drug - drug interactions, but a few days' interval between a COVID-19 vaccination and the use of CGRP mAbs is recommended to allow the accurate identification of the possible adverse effects, such as injection site reaction. Covid-19- and vaccination-related headache are known to occur. Whether CGRP-related drugs would be of benefit in these circumstances is not yet known.

Evaluation and treatment approaches for neurological post-acute sequelae of COVID-19: A consensus statement and scoping review from the global COVID-19 neuro research coalition

Post-acute neurological sequelae of COVID-19 affect millions of people worldwide, yet little data is available to guide treatment strategies for the most common symptoms. We conducted a scoping review of PubMed/Medline from 1/1/2020-4/1/2023 to identify studies addressing diagnosis and treatment of the most common post-acute neurological sequelae of COVID-19 including: cognitive impairment, sleep disorders, headache, dizziness/lightheadedness, fatigue, weakness, numbness/pain, anxiety, depression and post-traumatic stress disorder. Utilizing the available literature and international disease-specific society guidelines, we constructed symptom-based differential diagnoses, evaluation and management paradigms. This pragmatic, evidence-based consensus document may serve as a guide for a holistic approach to post-COVID neurological care and will complement future clinical trials by outlining best practices in the evaluation and treatment of post-acute neurological signs/symptoms.

Pitfalls and biases in neuroepidemiological studies of COVID-19 and the nervous system: a critical appraisal of the current evidence and future directions

BACKGROUND

Neurological manifestations frequently occur in individuals with COVID-19, manifesting during the acute phase, persisting beyond the resolution of acute symptoms, and appearing days or weeks after the initial onset of COVID-19 symptoms. However, predicting the incidence, course, and outcome of these neurological manifestations at the individual patient level remains challenging. Biases in study design and limitations in data collection may contribute to the inconsistency and limited validity of the reported findings. Herein, we focused on critically appraising pitfalls and biases of prior reports and provide guidance for improving the quality and standardization of future research. Patients with COVID-19 exhibit diverse demographic features, sociocultural backgrounds, lifestyle habits, and comorbidities, all of which can influence the severity and progression of the infection and its impact on other organ systems. Overlooked or undocumented comorbidities and related treatments may contribute to neurological sequelae, which may not solely be attributable to COVID-19. It is crucial to consider the potential side effects of vaccines in relation to neurological manifestations.

CONCLUSION

To investigate neurological manifestations of COVID-19, it is essential to employ valid and reliable diagnostic criteria and standard definitions of the factors of interest. Although population-based studies are lacking, well-defined inception cohorts, including hospitalized individuals, outpatients, and community residents, can serve as valuable compromises. These cohorts should be evaluated for the presence of common comorbidities, alongside documenting the primary non-neurological manifestations of the infectious disease. Lastly, patients with COVID-19 should be followed beyond the acute phase to assess the persistence, duration, and severity of neurological symptoms, signs, or diseases.

SARS-CoV-2 infects epithelial cells of the blood-cerebrospinal fluid barrier rather than endothelial cells or pericytes of the blood-brain barrier

BACKGROUND

As a consequence of SARS-CoV-2 infection various neurocognitive and neuropsychiatric symptoms can appear, which may persist for several months post infection. However, cell type-specific routes of brain infection and underlying mechanisms resulting in neuroglial dysfunction are not well understood.

METHODS

Here, we investigated the susceptibility of cells constituting the blood-brain barrier (BBB) and the blood-cerebrospinal fluid barrier (BCSFB) of the choroid plexus (ChP) to SARS-CoV-2 infection using human induced pluripotent stem cell (hiPSC)-derived cellular models and a ChP papilloma-derived epithelial cell line as well as ChP tissue from COVID-19 patients, respectively.

RESULTS

We noted a differential infectibility of hiPSC-derived brain microvascular endothelial cells (BMECs) depending on the differentiation method. Extended endothelial culture method (EECM)-BMECs characterized by a complete set of endothelial markers, good barrier properties and a mature immune phenotype were refractory to SARS-CoV-2 infection and did not exhibit an activated phenotype after prolonged SARS-CoV-2 inoculation. In contrast, defined medium method (DMM)-BMECs, characterized by a mixed endothelial and epithelial phenotype and excellent barrier properties were productively infected by SARS-CoV-2 in an ACE2-dependent manner. hiPSC-derived brain pericyte-like cells (BPLCs) lacking ACE2 expression were not susceptible to SARS-CoV-2 infection. Furthermore, the human choroid plexus papilloma-derived epithelial cell line HIBCPP, modeling the BCSFB was productively infected by SARS-CoV-2 preferentially from the basolateral side, facing the blood compartment. Assessment of ChP tissue from COVID-19 patients by RNA in situ hybridization revealed SARS-CoV-2 transcripts in ChP epithelial and ChP stromal cells.

CONCLUSIONS

Our study shows that the BCSFB of the ChP rather than the BBB is susceptible to direct SARS-CoV-2 infection. Thus, neuropsychiatric symptoms because of COVID-19 may rather be associated with dysfunction of the BCSFB than the BBB. Future studies should consider a role of the ChP in underlying neuropsychiatric symptoms following SARS-CoV-2 infection.

COVID-19 as a polymorphic inflammatory spectrum of diseases: a review with focus on the brain

There appear to be huge variations and aberrations in the reported data in COVID-19 2 years now into the pandemic. Conflicting data exist at almost every level and also in the reported epidemiological statistics across different regions. It is becoming clear that COVID-19 is a polymorphic inflammatory spectrum of diseases, and there is a wide range of inflammation-related pathology and symptoms in those infected with the virus. The host's inflammatory response to COVID-19 appears to be determined by genetics, age, immune status, health status and stage of disease. The interplay of these factors may decide the magnitude, duration, types of pathology, symptoms and prognosis in the spectrum of COVID-19 disorders, and whether neuropsychiatric disorders continue to be significant. Early and successful management of inflammation reduces morbidity and mortality in all stages of COVID-19.

Risk predict model using multi-drug resistant organism infection from Neuro-ICU patients: a retrospective cohort study

The aim of this study was to analyze the current situation and risk factors of multi-drug-resistant organism (MDRO) infection in Neuro-intensive care unit (ICU) patients, and to develop the risk predict model. The data was collected from the patients discharged from Neuro-ICU of grade-A tertiary hospital at Guizhou province from January 2018 to April 2020. Binary Logistics regression was used to analyze the data. The model was examined by receiver operating characteristic curve (ROC). The grouped data was used to verify the sensitivity and specificity of the model. A total of 297 patients were included, 131 patients infected with MDRO. The infection rate was 44.11%. The results of binary Logistics regression showed that tracheal intubation, artery blood pressure monitoring, fever, antibiotics, pneumonia were independent risk factors for MDRO infection in Neuro-ICU (P < 0.05), AUC = 0.887. The sensitivity and specificity of ROC curve was 86.3% and 76.9%. The risk prediction model had a good predictive effect on the risk of MDRO infection in Neuro ICU, which can evaluate the risk and provide reference for preventive treatment and nursing intervention.

ICU Delirium Is Associated with Cardiovascular Burden and Higher Mortality in Patients with Severe COVID-19 Pneumonia

BACKGROUND

COVID-19 can lead to functional disorders and complications, e.g., pulmonary, thromboembolic, and neurological. The neuro-invasive potential of SARS-CoV-2 may result in acute brain malfunction, which manifests as delirium as a symptom. Delirium is a risk factor for death among patients hospitalized due to critical illness. Taking the above into consideration, the authors investigated risk factors for delirium in COVID-19 patients and its influence on outcomes.

METHODS

A total of 335 patients hospitalized due to severe forms of COVID-19 were enrolled in the study. Data were collected from medical charts.

RESULTS

Delirium occurred among 21.5% of patients. In the delirium group, mortality was significantly higher compared to non-delirium patients (59.7% vs. 28.5%; p < 0.001). Delirium increased the risk of death, with an OR of 3.71 (95% CI 2.16-6.89; p < 0.001). Age, chronic atrial fibrillation, elevated INR, urea, and procalcitonin, as well as decreased phosphates, appeared to be the independent risk factors for delirium occurrence.

CONCLUSIONS

Delirium occurrence in patients with severe COVID-19 significantly increases the risk of death and is associated with a cardiovascular burden. Hypophosphatemia is a promising reversible factor to reduce mortality in this group of patients. However, larger studies are essential in this area.

Neurological Consequences, Mental Health, Physical Care, and Appropriate Nutrition in Long-COVID-19

SARS-CoV-2 pandemic has caused a collapse of the world health systems. Now, vaccines and more effective therapies have reversed this crisis but the scenario is further aggravated by the appearance of a new pathology, occurring as SARS-CoV-2 infection consequence: the long-COVID-19. This term is commonly used to describe signs and symptoms that continue or develop after acute infection of COVID-19 up to several months. In this review, the consequences of the disease on mental health and the neurological implications due to the long-COVID are described. Furthermore, the appropriate nutritional approach and some recommendations to relieve the symptoms of the pathology are presented. Data collected indicated that in the next future the disease will affect an increasing number of individuals and that interdisciplinary action is needed to counteract it.

Disability evaluation in patients with Guillain-Barre syndrome and SARS-CoV-2 infection

Objective

Several cases of Guillain-Barre syndrome (GBS) associated with SARS-CoV-2 infection have been described. This study illustrated the demographic, clinical, and neurophysiological characteristics of patients with GBS and COVID-19, as well as associated factors with disability at discharge.

Materials and methods

A retrospective analytical observational study was conducted. It included patients diagnosed with GBS admitted in a national reference center in Peru between 2019 and 2021. Epidemiological, clinical, neurophysiological, and cerebrospinal fluid data were analyzed. A multivariate analysis, using the generalized linear model, was performed, considering the presence of disability at discharge as the dependent variable.

Results

Eight-one subjects diagnosed with GBS were included. The mean age was 46.8 years (SD: 15.2), with a predominance of males (61.73%). The most frequent clinical presentation was the classic sensory-motor form in 74 cases (91.36%) with AIDP (82.35%) as the most frequent neurophysiological pattern in the group with COVID-19, while AMAN pattern predominated (59.26%) in those without COVID-19 (p = <0.000). The disability prevalence ratio at discharge between subjects with COVID-19 and those without COVID-19 was 1.89 (CI 1.06-3.34), p = 0.030, adjusted for age, sex, and neurophysiological subtype.

Conclusion

The neurophysiologic subtype AIDP, and a higher disability were associated with the presence of COVID-19.

Challenges to associate early onset epilepsy with COVID-19 autoimmune encephalitis: A case report

BACKGROUND

Diagnosis of coronavirus disease 2019 (COVID-19)-related neurological events in the pediatric population is challenging. Overlapping clinical picture of children with altered neurological state and inborn errors of metabolism, in addition to the frequency of asymptomatic COVID-19 cases, pose the main challenges for diagnosis. Diagnostic approaches to the onset post-COVID 19 subacute encephalopathy are still troublesome as seronegative autoimmune encephalitis (AIE) is reported.

CASE SUMMARY

A 27-mo-old boy was admitted for stormy refractory seizure of polymorphic semiology and altered mental status followed by various neuropsychiatric features that were suggestive of AIE. Brain magnetic resonance imaging and cerebrospinal fluid analysis were normal. Neither the immunological assessment, including viral serologies, antinuclear antibodies, autoimmune antibodies (NMDA, AMPA, CASPR2, LG11, GABARB, Hu, Yo, Ri, CV2, PNMA2, SOX1, Titin, amphiphysin, Recoverin), nor the metabolic assessment for lactate and pyruvate showed significant anomaly. Both positive history of COVID-19 infection and the findings of characteristic repetitive extreme delta brush played a key role in the diagnosis of COVID-19-related AIE. A remarkable improvement in the state of the child was noted after two pulse doses of intravenous Veino-globulin and high dose of intravenous Corticosteroid.

CONCLUSION

Diagnostic biomarkers for AIE might aid effective treatment.

Importance of Magnesium Status in COVID-19

A large amount of published research points to the interesting concept (hypothesis) that magnesium (Mg) status may have relevance for the outcome of COVID-19 and that Mg could be protective during the COVID disease course. As an essential element, Mg plays basic biochemical, cellular, and physiological roles required for cardiovascular, immunological, respiratory, and neurological functions. Both low serum and dietary Mg have been associated with the severity of COVID-19 outcomes, including mortality; both are also associated with COVID-19 risk factors such as older age, obesity, type 2 diabetes, kidney disease, cardiovascular disease, hypertension, and asthma. In addition, populations with high rates of COVID-19 mortality and hospitalization tend to consume diets high in modern processed foods, which are generally low in Mg. In this review, we review the research to describe and consider the possible impact of Mg and Mg status on COVID-19 showing that (1) serum Mg between 2.19 and 2.26 mg/dL and dietary Mg intakes > 329 mg/day could be protective during the disease course and (2) inhaled Mg may improve oxygenation of hypoxic COVID-19 patients. In spite of such promise, oral Mg for COVID-19 has thus far been studied only in combination with other nutrients. Mg deficiency is involved in the occurrence and aggravation of neuropsychiatric complications of COVID-19, including memory loss, cognition, loss of taste and smell, ataxia, confusion, dizziness, and headache. Potential of zinc and/or Mg as useful for increasing drug therapy effectiveness or reducing adverse effect of anti-COVID-19 drugs is reviewed. Oral Mg trials of patients with COVID-19 are warranted.

Cost-Effectiveness Analysis of COVID-19 Inactivated Vaccines in Reducing the Economic Burden of Ischaemic Stroke after SARS-CoV-2 Infection

Due to significant economic burden and disability from ischaemic stroke and the relationship between ischaemic stroke and SARS-CoV-2 infection, we aimed to explore the cost-effectiveness of the two-dose inactivated COVID-19 vaccination program in reducing the economic burden of ischaemic stroke after SARS-CoV-2 infection. We constructed a decision-analytic Markov model to compare the two-dose inactivated COVID-19 vaccination strategy to the no vaccination strategy using cohort simulation. We calculated incremental cost-effectiveness ratios (ICERs) to evaluate the cost-effectiveness and used number of the ischaemic stroke cases after SARS-CoV-2 infection and quality-adjusted life-years (QALYs) to assess effects. Both one-way deterministic sensitivity analysis and probabilistic sensitivity analysis were performed to assess the robustness of the results. We found that the two-dose inactivated vaccination strategy reduced ischaemic stroke cases after SARS-CoV-2 infection by 80.89% (127/157) with a USD 1.09 million as vaccination program cost, saved USD 3675.69 million as direct health care costs and gained 26.56 million QALYs compared with no vaccination strategy among 100,000 COVID-19 patients (ICER < 0 per QALY gained). ICERs remained robust in sensitivity analysis. The proportion of older patients and the proportion of two-dose inactivated vaccination among older people were the critical factors that affected ICER. This study suggests the importance of COVID-19 vaccination is not only in preventing the spread of infectious diseases, but also in considering its long-term value in reducing the economic burden of non-communicable diseases such as ischaemic stroke after SARS-CoV-2 infection.

Pathogenesis Underlying Neurological Manifestations of Long COVID Syndrome and Potential Therapeutics

The development of long-term symptoms of coronavirus disease 2019 (COVID-19) more than four weeks after primary infection, termed "long COVID" or post-acute sequela of COVID-19 (PASC), can implicate persistent neurological complications in up to one third of patients and present as fatigue, "brain fog", headaches, cognitive impairment, dysautonomia, neuropsychiatric symptoms, anosmia, hypogeusia, and peripheral neuropathy. Pathogenic mechanisms of these symptoms of long COVID remain largely unclear; however, several hypotheses implicate both nervous system and systemic pathogenic mechanisms such as SARS-CoV2 viral persistence and neuroinvasion, abnormal immunological response, autoimmunity, coagulopathies, and endotheliopathy. Outside of the CNS, SARS-CoV-2 can invade the support and stem cells of the olfactory epithelium leading to persistent alterations to olfactory function. SARS-CoV-2 infection may induce abnormalities in innate and adaptive immunity including monocyte expansion, T-cell exhaustion, and prolonged cytokine release, which may cause neuroinflammatory responses and microglia activation, white matter abnormalities, and microvascular changes. Additionally, microvascular clot formation can occlude capillaries and endotheliopathy, due to SARS-CoV-2 protease activity and complement activation, can contribute to hypoxic neuronal injury and blood-brain barrier dysfunction, respectively. Current therapeutics target pathological mechanisms by employing antivirals, decreasing inflammation, and promoting olfactory epithelium regeneration. Thus, from laboratory evidence and clinical trials in the literature, we sought to synthesize the pathophysiological pathways underlying neurological symptoms of long COVID and potential therapeutics.

Links between COVID-19 and Parkinson's disease/Alzheimer's disease: reciprocal impacts, medical care strategies and underlying mechanisms

The impact of coronavirus disease 2019 (COVID-19) pandemic on patients with neurodegenerative diseases and the specific neurological manifestations of COVID-19 have aroused great interest. However, there are still many issues of concern to be clarified. Therefore, we review the current literature on the complex relationship between COVID-19 and neurodegenerative diseases with an emphasis on Parkinson's disease (PD) and Alzheimer's disease (AD). We summarize the impact of COVID-19 infection on symptom severity, disease progression, and mortality rate of PD and AD, and discuss whether COVID-19 infection could trigger PD and AD. In addition, the susceptibility to and the prognosis of COVID-19 in PD patients and AD patients are also included. In order to achieve better management of PD and AD patients, modifications of care strategies, specific drug therapies, and vaccines during the pandemic are also listed. At last, mechanisms underlying the link of COVID-19 with PD and AD are reviewed.

Mechanisms, Effects, and Management of Neurological Complications of Post-Acute Sequelae of COVID-19 (NC-PASC)

With a growing number of patients entering the recovery phase following infection with SARS-CoV-2, understanding the long-term neurological consequences of the disease is important to their care. The neurological complications of post-acute sequelae of SARS-CoV-2 infection (NC-PASC) represent a myriad of symptoms including headaches, brain fog, numbness/tingling, and other neurological symptoms that many people report long after their acute infection has resolved. Emerging reports are being published concerning COVID-19 and its chronic effects, yet limited knowledge of disease mechanisms has challenged therapeutic efforts. To address these issues, we review broadly the literature spanning 2020-2022 concerning the proposed mechanisms underlying NC-PASC, outline the long-term neurological sequelae associated with COVID-19, and discuss potential clinical interventions.

Cortical Grey matter volume depletion links to neurological sequelae in post COVID-19 "long haulers"

OBJECTIVE

COVID-19 (SARS-CoV-2) has been associated with neurological sequelae even in those patients with mild respiratory symptoms. Patients experiencing cognitive symptoms such as "brain fog" and other neurologic sequelae for 8 or more weeks define "long haulers". There is limited information regarding damage to grey matter (GM) structures occurring in COVID-19 "long haulers". Advanced imaging techniques can quantify brain volume depletions related to COVID-19 infection which is important as conventional Brain MRI often fails to identify disease correlates. 3-dimensional voxel-based morphometry (3D VBM) analyzes, segments and quantifies key brain volumes allowing comparisons between COVID-19 "long haulers" and normative data drawn from healthy controls, with values based on percentages of intracranial volume.

METHODS

This is a retrospective single center study which analyzed 24 consecutive COVID-19 infected patients with long term neurologic symptoms. Each patient underwent Brain MRI with 3D VBM at median time of 85 days following laboratory confirmation. All patients had relatively mild respiratory symptoms not requiring oxygen supplementation, hospitalization, or assisted ventilation. 3D VBM was obtained for whole brain and forebrain parenchyma, cortical grey matter (CGM), hippocampus, and thalamus.

RESULTS

The results demonstrate a statistically significant depletion of CGM volume in 24 COVID-19 infected patients. Reduced CGM volume likely influences their long term neurological sequelae and may impair post COVID-19 patient's quality of life and productivity.

CONCLUSION

This study contributes to understanding effects of COVID-19 infection on patient's neurocognitive and neurological function, with potential for producing serious long term personal and economic consequences, and ongoing challenges to public health systems.

Depression and brain fog as long-COVID mental health consequences: Difficult, complex and partially successful treatment of a 72-year-old patient-A case report

SARS-CoV-2 (COVID-19) infection can result in long-term health consequences i.e., long COVID. The clinical manifestations of long COVID include depression, anxiety, brain fog with cognitive dysfunction, memory issues, and fatigue. These delayed effects of COVID-19 occur in up to 30% of people who have had an acute case of COVID-19. In this case report, a 72-year-old, fully vaccinated patient without pre-existing somatic or mental illnesses, or other relevant risk factors was diagnosed with long COVID. Nine months following an acute COVID-19 infection, the patient's depressive symptoms improved, but memory and concentration difficulties persisted, and the patient remains unable to resume work. These long-term symptoms are possibly linked to micro-hemorrhages detected during examinations of the patient's brain following COVID-19 infection. Patient treatment was complex, and positive results were attained via antidepressants and non-drug therapies e.g., art, music, drama, dance and movement therapy, physiotherapy, occupational therapy, and psychotherapy.

[Modern ideas about the relationship between fibromyalgia and mental disorders]

Fibromyalgia (FM) is a pain syndrome with a high burden and an understudied etiology and pathogenesis. There is now considerable evidence that FM has a strong bidirectional relationship with psychiatric disorders and is associated with certain personality traits that contribute to the severity of key somatic symptoms and affect overall prognosis. In this article, the authors present data from recent epidemiological and neurobiological studies, discuss the multilevel relationship between FM and psychiatric disorders, and briefly review approaches to the treatment of co-morbid conditions.

COVID-19: Brain Effects

Severe acute respiratory syndrome coronavirus 2, the novel coronavirus responsible for the coronavirus disease (COVID-19), affects the brain. Neurologic and neuropsychiatric symptoms may manifest in the acute and post-acute phases of illness. The vulnerability of the brain with aging further increases the burden of disease in the elderly, who are at the highest risk of complications and death from COVID-19. The mechanisms underlying the effects of COVID-19 on the brain are not fully known. Emerging evidence vis-à-vis pathogenesis and etiologies of COVID-19 brain effects is promising and may pave the way for future research and development of interventions.

Persistent unilateral diaphragmatic paralysis in the course of Coronavirus Disease 2019 pneumonia: a case report

Coronavirus Disease 2019 infections can cause a wide range of symptoms, particularly in the respiratory system. Diaphragmatic paralysis is a rare condition that is poorly documented in the literature. We present the case of a 38-year-old Caucasian male adult who developed unilateral diaphragmatic paralysis during the course of the disease. The patient presented to the Emergency Department with fever, cough, and dyspnea, was admitted, and was immediately fitted with a high flow nasal cannula. When his condition worsened eight days later, he was admitted to the Intensive Care Unit and a tracheostomy was performed. A CT scan of the chest revealed significant left diaphragm elevation. On the 48th day, the patient gradually improved and was discharged. The paralysis of the diaphragm persisted three months later in the follow-up examination. This case illustrates a possible neuromuscular virus invasion that may have an impact on the patient's health after discharge.

Neuro-Immune Interactions in Severe COVID-19 Infection

SARS-CoV-2 is a new coronavirus that has affected the world since 2019. Interstitial pneumonia is the most common clinical presentation, but additional symptoms have been reported, including neurological manifestations. Severe forms of infection, especially in elderly patients, present as an excessive inflammatory response called "cytokine storm", which can lead to acute respiratory distress syndrome (ARDS), multiorgan failure and death. Little is known about the relationship between symptoms and clinical outcomes or the characteristics of virus-host interactions. The aim of this narrative review is to highlight possible links between neurological involvement and respiratory damage mediated by pathological inflammatory pathways in SARS-CoV-2 infection. We will focus on neuro-immune interactions and age-related immunity decline and discuss some pathological mechanisms that contribute to negative outcomes in COVID-19 patients. Furthermore, we will describe available therapeutic strategies and their effects on COVID-19 neurological symptoms.

Neurologic symptoms and signs observed in critical COVID-19 patients may be precursors of existing cerebrovascular disease

Introduction: Although COVID-19 disease often includes respiratory system findings, that affects the gastrointestinal system, circulatory system, coagulation system and neurological system. In this study, we identified the neurological signs and symptoms observed in critical COVID-19 patients. Material and Method: This retrospective study reviewed 595 COVID-19 patients admitted to our intensive care unit (ICU) between January to June 2020. Patients with neurologic symptoms that were divided into two groups were diagnosed neurological disease (group ND) and non-neurological disease (group non-ND). Clinical signs and symptoms, radiological findings, demographic data (age, gender, presence of comorbidities), white blood cell (WBC), lymphocyte, platelet, lactic acid, glucose, and D-dimer levels, length of hospitalization, requirement of mechanical ventilation, and mortality were recorded for each patient. Results: Neurologic symptoms were observed in 148 (24.8%) patients. Of these, 44 patients were diagnosed neurological disease and 104 patients were non- neurological disease. The prevalence of neurologic symptoms was significantly higher in group ND. The rate of acute ischemic cerebrovascular disease in 595 critical COVID-19 patients was 6.2%. Conclusion: Presence of cerebrovascular diseases should be suspected in COVID-19patients with paresis, altered consciousness, numbness, taste/smell disorders, and plegia. The rate of ischemic cerebrovascular disease was approximately seven times higher than the rate of hemorrhagic cerebrovascular disease in critically COVID-19 patients.

Child Neurology: Hemiconvulsion-Hemiplegia-Epilepsy Syndrome in the Setting of COVID-19 Infection and Multisystem Inflammatory Syndrome

Hemiconvulsion-hemiplegia-epilepsy (HHE) syndrome is a rare pediatric epilepsy syndrome characterized by prolonged focal febrile convulsive status epilepticus with unilateral hemispheric cerebral edema, followed by the subsequent development of hemiplegia, global atrophy of the affected hemisphere, and epilepsy. The pathophysiology of HHE syndrome remains poorly understood though is clearly multifactorial. Factors thus far implicated are hyperthermia, proinflammatory state, and cytotoxic edema from prolonged ictal activity. Prognosis is variable, from the resolution of hemiplegia and seizures to permanent hemiparesis and refractory epilepsy. We describe a 2-year-old boy who presented with superrefractory focal status epilepticus in the setting of acute coronavirus infectious disease-2019 (COVID-19) and multisystem inflammatory syndrome in children (MIS-C). He had right-sided hemiplegia on neurologic examination, and an MRI examination of the brain showed left cerebral hemispheric edema consistent with HHE syndrome. Our case represents the first report in the literature on HHE syndrome in the setting of acute COVID-19 and MIS-C.

Post-COVID-19 Parkinsonism and Parkinson's Disease Pathogenesis: The Exosomal Cargo Hypothesis

Parkinson's disease (PD) is the second most prevalent neurodegenerative disease after Alzheimer's disease, globally. Dopaminergic neuron degeneration in substantia nigra pars compacta and aggregation of misfolded alpha-synuclein are the PD hallmarks, accompanied by motor and non-motor symptoms. Several viruses have been linked to the appearance of a post-infection parkinsonian phenotype. Coronavirus disease 2019 (COVID-19), caused by emerging severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection, has evolved from a novel pneumonia to a multifaceted syndrome with multiple clinical manifestations, among which neurological sequalae appear insidious and potentially long-lasting. Exosomes are extracellular nanovesicles bearing a complex cargo of active biomolecules and playing crucial roles in intercellular communication under pathophysiological conditions. Exosomes constitute a reliable route for misfolded protein transmission, contributing to PD pathogenesis and diagnosis. Herein, we summarize recent evidence suggesting that SARS-CoV-2 infection shares numerous clinical manifestations and inflammatory and molecular pathways with PD. We carry on hypothesizing that these similarities may be reflected in exosomal cargo modulated by the virus in correlation with disease severity. Travelling from the periphery to the brain, SARS-CoV-2-related exosomal cargo contains SARS-CoV-2 RNA, viral proteins, inflammatory mediators, and modified host proteins that could operate as promoters of neurodegenerative and neuroinflammatory cascades, potentially leading to a future parkinsonism and PD development.

Effects of vaccination, new SARS-CoV-2 variants and reinfections on post-COVID-19 complications

Post-COVID-19 complications involve a variety of long-lasting health complications emerging in various body systems. Since the prevalence of post-COVID-19 complications ranges from 8-47% in COVID-19 survivors, it represents a formidable challenge to COVID-19 survivors and the health care system. Post-COVID-19 complications have already been studied in the connection to risk factors linked to their higher probability of occurrence and higher severity, potential mechanisms underlying the pathogenesis of post-COVID-19 complications, and their functional and structural correlates. Vaccination status has been recently revealed to represent efficient prevention from long-term and severe post-COVID-19 complications. However, the exact mechanisms responsible for vaccine-induced protection against severe and long-lasting post-COVID-19 complications remain elusive. Also, to the best of our knowledge, the effects of new SARS-CoV-2 variants and SARS-CoV-2 reinfections on post-COVID-19 complications and their underlying pathogenesis remain to be investigated. This hypothesis article will be dedicated to the potential effects of vaccination status, SARS-CoV-2 reinfections, and new SARS-CoV-2 variants on post-COVID-19 complications and their underlying mechanisms Also, potential prevention strategies against post-COVID complications will be discussed.

An Overview of Neurological and Psychiatric Complications During Post-COVID Period: A Narrative Review

The coronavirus disease 2019 (COVID-19), induced by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a multi-organ and multi-system disease with high morbidity and mortality in severe cases due to respiratory failure and severe cardiovascular events. However, the various manifestations of neurological and psychiatric (N/P) systems of COVID-19 should not be neglected. Some clinical studies have reported a high risk of N/P disorders in COVID-19 and post-COVID-19 patients and that their outcomes were positively associated with the disease severity. These clinical manifestations could attribute to direct SARS-CoV-2 invasion into the central nervous system (CNS), which is often complicated by systemic hypoxia, the dysfunctional activity of the renin-angiotensin system and other relevant pathological changes. These changes may remain long term and may even lead to persistent post-COVID consequences on the CNS, such as memory, attention and focus issues, persistent headaches, lingering loss of smell and taste, enduring muscle aches and chronic fatigue. Mild confusion and coma are serious adverse outcomes of neuropathological manifestations in COVID-19 patients, which could be diversiform and vary at different stages of the clinical course. Although lab investigations and neuro-imaging findings may help quantify the disease's risk, progress and prognosis, large-scale and persistent multicenter clinical cohort studies are needed to evaluate the impact of COVID-19 on the N/P systems. However, we used "Boolean Operators" to search for relevant research articles, reviews and clinical trials from PubMed and the ClinicalTrials dataset for "COVID-19 sequelae of N/P systems during post-COVID periods" with the time frame from December 2019 to April 2022, only found 42 in 254,716 COVID-19-related articles and 2 of 7931 clinical trials involved N/P sequelae during post-COVID periods. Due to the increasing number of infected cases and the incessant mutation characteristics of this virus, diagnostic and therapeutic guidelines for N/P manifestations should be further refined.

Perspective: COVID-19 and Its Neurologic Sequelae

COVID-19 led to a catastrophic, international, public health crisis after its first detection in 2019 [1]. Though it is primarily a respiratory virus, it impacts the central and peripheral nervous systems leading to further COVID-19-associated disability [2]. This Perspective reviews our current understanding of the neurological sequelae of COVID-19 and the gaps in our understanding of their treatment and epidemiology.

Immunopathology of SARS-COV-2 and Neurological Manifestations Caused by the Virus: A Review of the Literature

SARS-CoV-2 (Severe Acute Respiratory Syndrome), or the disease caused by the new coronavirus, the source of COVID-19, has rapidly turned into a pandemic, a danger with an impact on human health.

Various neurological manifestations associated with SARS-CoV-2 infection have been reported in the literature and are currently classified into central nervous system-related (headache, dizziness, cerebrovascular disease, epilepsy) and peripheral nervous system-related (anosmia, ageusia, muscle pain, Guillain-Barré syndrome). However, it remains difficult to establish a link between these neurological manifestations and the underlying mechanisms.

In the current context, physicians need to be aware of the broad spectrum of neurological symptoms associated with infection with this virus for early diagnosis and appropriate treatment.

In this review, we aim to highlight the pathways of SARS-CoV-2 virus invasion, the neurotropism of the virus and the immunopathological mechanisms underlying the neurological manifestations associated with COVID-19 disease.