Neuropsychiatric and Cognitive Outcomes in Patients 6 Months After COVID-19 Requiring Hospitalization Compared With Matched Control Patients Hospitalized for Non-COVID-19 Illness

Outcomes and Management After COVID-19 Critical Illness

TOPIC IMPORTANCE

COVID-19 has caused > 7 million deaths worldwide since its onset in 2019. Although the severity of illness has varied throughout the pandemic, critical illness related to COVID-19 persists. Survivors of COVID-19 critical illness can be left with sequelae of both the SARS-CoV-2 virus and long-term effects of critical illness included within post-intensive care syndrome. Given the complexity and heterogeneity of COVID-19 critical illness, the biopsychosocial-ecological model can aid in evaluation and treatment of survivors, integrating interactions among physical, cognitive, and psychological domains, as well as social systems and environments.

REVIEW FINDINGS

Prolonged illness after COVID-19 critical illness generally can be classified into effects on physical, cognitive, and psychosocial function, with much interaction among the various effects, and includes a wide range of symptoms such as ICU-acquired weakness, prolonged respiratory symptoms, cognitive changes, post-traumatic stress disorder post-traumatic stress disorder, anxiety, and depression. Risk factors for COVID-19 critical illness developing are complex and include preexisting factors, disease course, and specifics of hospitalization in addition to psychological comorbidities and socioenvironmental factors. Recovery trajectories are not well defined, and management requires a comprehensive, interdisciplinary, and individualized approach to care.

SUMMARY

The onset of vaccinations, new therapeutics, and new strains of SARS-CoV-2 virus have decreased COVID-19 mortality; however, the number of survivors of COVID-19 critical illness remains high. A biopsychosocial-ecological approach is recommended to guide care of COVID-19 critical illness survivors.

Neurocognitive Impairment in Post-COVID-19 Condition in Adults: Narrative Review of the Current Literature

The severe acute respiratory syndrome coronavirus 2 virus has, up to the time of this article, resulted in >770 million cases of COVID-19 illness worldwide, and approximately 7 million deaths, including >1.1 million in the United States. Although defined as a respiratory virus, early in the pandemic, it became apparent that considerable numbers of people recovering from COVID-19 illness experienced persistence or new onset of multi-system health problems, including neurologic and cognitive and behavioral health concerns. Persistent multi-system health problems are defined as Post-COVID-19 Condition (PCC), Post-Acute Sequelae of COVID-19, or Long COVID. A significant number of those with PCC report cognitive problems. This paper reviews the current state of scientific knowledge on persisting cognitive symptoms in adults following COVID-19 illness. A brief history is provided of the emergence of concerns about persisting cognitive problems following COVID-19 illness and the definition of PCC. Methodologic factors that complicate clear understanding of PCC are reviewed. The review then examines research on patterns of cognitive impairment that have been found, factors that may contribute to increased risk, behavioral health variables, and interventions being used to ameliorate persisting symptoms. Finally, recommendations are made about ways neuropsychologists can improve the quality of existing research.

Possible temporal relationship between SARS-CoV-2 infection and anti-NMDA receptor encephalitis: a meta-analysis

The global impact of SARS-CoV-2 infection has raised concerns about secondary diseases beyond acute illness. This review explores the significance and potential underlying mechanisms of how SARS-CoV-2 infection might elicit an immune response targeting N-methyl-D-aspartate (NMDA) receptors, and its implications for autoimmune-driven neuropsychiatric manifestations. We identified 19 published case reports of NMDA receptor encephalitis associated with SARS-CoV-2 infection or vaccination by a systematic literature search. The significance of these reports was limited since it is not clear if a coincidental or causal relationship exists between SARS-CoV-2 infection or vaccination and manifestation of NMDA receptor encephalitis. The included studies were hampered by difficulties in establishing if these patients had pre-existing NMDA receptor antibodies which entered the brain by infection- or vaccination-associated transient blood-brain barrier leakage. In addition, four cases had comorbid ovarian teratoma, which is a known trigger for development of NMDA receptor encephalitis. Considering that billions of people have contracted COVID-19 or have been vaccinated against this virus, the publication of only 19 case reports with a possible link to NMDA receptor encephalitis, indicates that it is rare. In conclusion, these findings do not support the case that SARS-CoV-2 infection or vaccination led to an increase of existing or de novo encephalitis mediated by an autoimmune response targeting NMDA receptor function. Nevertheless, this work underscores the importance of ongoing vigilance in monitoring viral outbreaks and their potential impact on the central nervous system through basic, epidemiological and translational research.

Cognition and Memory after Covid-19 in a Large Community Sample

BACKGROUND

Cognitive symptoms after coronavirus disease 2019 (Covid-19), the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), are well-recognized. Whether objectively measurable cognitive deficits exist and how long they persist are unclear.

METHODS

We invited 800,000 adults in a study in England to complete an online assessment of cognitive function. We estimated a global cognitive score across eight tasks. We hypothesized that participants with persistent symptoms (lasting ≥12 weeks) after infection onset would have objectively measurable global cognitive deficits and that impairments in executive functioning and memory would be observed in such participants, especially in those who reported recent poor memory or difficulty thinking or concentrating ("brain fog").

RESULTS

Of the 141,583 participants who started the online cognitive assessment, 112,964 completed it. In a multiple regression analysis, participants who had recovered from Covid-19 in whom symptoms had resolved in less than 4 weeks or at least 12 weeks had similar small deficits in global cognition as compared with those in the no-Covid-19 group, who had not been infected with SARS-CoV-2 or had unconfirmed infection (-0.23 SD [95% confidence interval {CI}, -0.33 to -0.13] and -0.24 SD [95% CI, -0.36 to -0.12], respectively); larger deficits as compared with the no-Covid-19 group were seen in participants with unresolved persistent symptoms (-0.42 SD; 95% CI, -0.53 to -0.31). Larger deficits were seen in participants who had SARS-CoV-2 infection during periods in which the original virus or the B.1.1.7 variant was predominant than in those infected with later variants (e.g., -0.17 SD for the B.1.1.7 variant vs. the B.1.1.529 variant; 95% CI, -0.20 to -0.13) and in participants who had been hospitalized than in those who had not been hospitalized (e.g., intensive care unit admission, -0.35 SD; 95% CI, -0.49 to -0.20). Results of the analyses were similar to those of propensity-score-matching analyses. In a comparison of the group that had unresolved persistent symptoms with the no-Covid-19 group, memory, reasoning, and executive function tasks were associated with the largest deficits (-0.33 to -0.20 SD); these tasks correlated weakly with recent symptoms, including poor memory and brain fog. No adverse events were reported.

CONCLUSIONS

Participants with resolved persistent symptoms after Covid-19 had objectively measured cognitive function similar to that in participants with shorter-duration symptoms, although short-duration Covid-19 was still associated with small cognitive deficits after recovery. Longer-term persistence of cognitive deficits and any clinical implications remain uncertain. (Funded by the National Institute for Health and Care Research and others.).

Long-term follow-up of brain regional changes and the association with cognitive impairment in quarantined COVID-19 survivors

OBJECTIVE

This study aimed to evaluate the neuropsychiatric symptoms of quarantined COVID-19 survivors 15 months after discharge and explore its potential association with structural and functional brain changes and inflammation.

METHODS

A total of 51 quarantined COVID-19 survivors and 74 healthy controls were included in this study. Cognitive function was assessed using the THINC-integrated tool. Structural brain changes were examined through both surface- and volume-based analyses, and functional changes were assessed using resting-state amplitude low-frequency fluctuation (ALFF). Serum inflammatory markers were measured by a multiplexed flow cytometric assay.

RESULTS

COVID-19 survivors exhibited subjective cognitive decline compared to healthy controls, despite no significant differences in objective cognitive tasks. Structural analysis revealed significantly increased gray matter volume and cortical surface area in the left transverse temporal gyrus (Heschl's gyrus) in quarantined COVID-19 survivors. This enlargement was negatively correlated with cognitive impairment. The ALFF analysis showed decreased neural activity in multiple brain regions. Elevated levels of serum inflammatory markers were also found in COVID-19 survivors, including MIP-1a, MIP-1b, TNF-a, and IL-8, which correlated with functional abnormalities.

CONCLUSIONS

Our findings indicate a subjective cognitive decline in quarantined COVID-19 survivors 15 months after discharge, which is associated with brain structural alterations in the left Heschl's gyrus. The observed elevation of inflammatory markers suggests a potential mechanism involving inflammation-induced neurogenesis. These results contribute to our understanding of the possible mechanisms underlying long-term neuropsychiatric consequences of COVID-19 and highlight the need for further research to develop targeted interventions.

Cognitive and mental health trajectories of COVID-19: Role of hospitalisation and long-COVID symptoms

BACKGROUND

There is considerable evidence of cognitive impairment post COVID-19, especially in individuals with long-COVID symptoms, but limited research objectively evaluating whether such impairment attenuates or resolves over time, especially in young and middle-aged adults.

METHODS

Follow-up assessments (T2) of cognitive function (processing speed, attention, working memory, executive function, memory) and mental health were conducted in 138 adults (18-69 years) who had been assessed 6 months earlier (T1). Of these, 88 had a confirmed history of COVID-19 at T1 assessment (≥20 days post-diagnosis) and were also followed-up on COVID-19-related symptoms (acute and long-COVID); 50 adults had no known COVID-19 history at any point up to their T2 assessment.

RESULTS

From T1 to T2, a trend-level improvement occurred in intra-individual variability in processing speed in the COVID, relative to the non-COVID group. However, longer response/task completion times persisted in participants with COVID-19-related hospitalisation relative to those without COVID-19-related hospitalisation and non-COVID controls. There was a significant reduction in long-COVID symptom load, which correlated with improved executive function in non-hospitalised COVID-19 participants. The COVID group continued to self-report poorer mental health, irrespective of hospitalisation history, relative to non-COVID group.

CONCLUSIONS

Although some cognitive improvement has occurred over a 6-month period in young and middle-aged COVID-19 survivors, cognitive impairment persists in those with a history of COVID-19-related hospitalisation and/or long-COVID symptoms. Continuous follow-up assessments are required to determine whether cognitive function improves or possibly worsens, over time in hospitalised and long-COVID participants.

Cognition and psychological well-being in adults with post COVID-19 condition and analyses of symptom sequelae

OBJECTIVE

As the coronavirus disease 2019 (COVID-19) pandemic moves into its fourth year, gaining a better clinical understanding of individuals with post COVID-19 condition is paramount. The current study examined the neurocognitive and psychological status of adults with post COVID-19 condition, as well as explored the impact of high psychological burden on objective neurocognitive functioning and the relationship between subjective cognitive concerns and objective neurocognitive findings.

METHOD

Valid neuropsychological assessments were completed with 51 symptomatic adults who were 297.55 days, on average, following a confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Participants completed brief self-report depression, anxiety, and PTSD questionnaires, a questionnaire with subjective ratings of cognitive abilities, and standardized neurocognitive tests that examined performance validity, attention, processing speed, verbal learning and memory, naming, visual construction, and executive functioning.

RESULTS

The participants were mostly Caucasian (80.39%), middle-aged (average 47.37 years), women (82.35%), who were never hospitalized (86.27%). Despite all individuals reporting cognitive problems in daily life, mean performances on objective testing did not reveal any neurocognitive deficits (at or below the 8th percentile) at a group level. Approximately half (49.02%) of the participants reported co-occurring mental health symptoms that were considered clinically elevated based on questionnaire results. High psychological symptom burden was associated with greater subjective cognitive difficulties but did not result in neurocognitive dysfunction on objective testing.

CONCLUSIONS

This study contributes to the literature regarding post COVID-19 condition in adults including the relationship between the cognitive and psychological symptoms. Results are summarized in key clinical learning points.

The burden of persistent symptoms after COVID-19 (long COVID): a meta-analysis of controlled studies in children and adults

BACKGROUND

Previous meta-analyses estimating the prevalence of the post-COVID-19 condition (PCC) were confounded by the lack of negative control groups. This may result in an overestimation of the prevalence of those experiencing PCC, as these symptoms are non-specific and common in the general population. In this study, we aimed to compare the burden of persistent symptoms among COVID-19 survivors relative to COVID-19-negative controls.

METHODS

A systematic literature search was conducted using the following databases (PubMed, Web of Science, and Scopus) until July 2023 for comparative studies that examined the prevalence of persistent symptoms in COVID-19 survivors. Given that many of the symptoms among COVID-19 survivors overlap with post-hospitalization syndrome and post-intensive care syndrome, we included studies that compare the prevalence of persistent symptoms in hospitalized COVID-19 patients relative to non-COVID-19 hospitalized patients and in non-hospitalized COVID-19 patients relative to healthy controls that reported outcomes after at least 3 months since infection. The results of the meta-analysis were reported as odds ratios with a 95% confidence interval based on the random effects model.

RESULTS

Twenty articles were included in this study. Our analysis of symptomatology in non-hospitalized COVID-19 patients compared to negative controls revealed that the majority of symptoms examined were not related to COVID-19 infection and appeared equally prevalent in both cohorts. However, non-COVID-19 hospitalized patients had higher odds of occurrence of certain symptoms like anosmia, ageusia, fatigue, dyspnea, and brain fog (P < 0.05). Particularly, anosmia and ageusia showed substantially elevated odds relative to the negative control group at 11.27 and 9.76, respectively, P < 0.05. In contrast, analysis of hospitalized COVID-19 patients compared to those hospitalized for other indications did not demonstrate significantly higher odds for the tested symptoms.

CONCLUSIONS

The persistent symptoms in COVID-19 survivors may result from hospitalization for causes unrelated to COVID-19 and are commonly reported among the general population. Although certain symptoms exhibited higher odds in non-hospitalized COVID-19 patients relative to controls, these symptoms are common post-viral illnesses. Therefore, the persistent symptoms after COVID-19 may not be unique to SARS-CoV-2. Future studies including well-matched control groups when investigating persistent symptoms in COVID-19 survivors are warranted to draw a firm conclusion.

Cognitive impairment in post-acute COVID-19 syndrome: a scoping review

Emerging studies indicate the persistence of symptoms beyond the acute phase of COVID-19. Cognitive impairment has been observed in certain individuals for months following infection. Currently, there is limited knowledge about the specific cognitive domains that undergo alterations during the post-acute COVID-19 syndrome and the potential impact of disease severity on cognition. The aim of this review is to examine studies that have reported cognitive impairment in post-acute COVID-19, categorizing them into subacute and chronic phases. The methodology proposed by JBI was followed in this study. The included studies were published between December 2019 and December 2022. The search was conducted in PubMed, PubMed PMC, BVS - BIREME, Embase, SCOPUS, Cochrane, Web of Science, Proquest, PsycInfo, and EBSCOHost. Data extraction included specific details about the population, concepts, context, and key findings or recommendations relevant to the review objectives. A total of 7,540 records were identified and examined, and 47 articles were included. The cognitive domains most frequently reported as altered 4 to 12 weeks after acute COVID-19 were language, episodic memory, and executive function, and after 12 weeks, the domains most affected were attention, episodic memory, and executive function. The results of this scoping review highlight that adults with post-acute COVID-19 syndrome may have impairment in specific cognitive domains.

Brain Health After COVID-19, Pneumonia, Myocardial Infarction, or Critical Illness

Importance

Brain health is most likely compromised after hospitalization for COVID-19; however, long-term prospective investigations with matched control cohorts and face-to-face assessments are lacking.

Objective

To assess whether long-term cognitive, psychiatric, or neurological complications among patients hospitalized for COVID-19 differ from those among patients hospitalized for other medical conditions of similar severity and from healthy controls.

Design, Setting, and Participants

This prospective cohort study with matched controls was conducted at 2 academic hospitals in Copenhagen, Denmark. The case cohort comprised patients with COVID-19 hospitalized between March 1, 2020, and March 31, 2021. Control cohorts consisted of patients hospitalized for pneumonia, myocardial infarction, or non-COVID-19 intensive care-requiring illness between March 1, 2020, and June 30, 2021, and healthy age- and sex-matched individuals. The follow-up period was 18 months; participants were evaluated between November 1, 2021, and February 28, 2023.

Exposures

Hospitalization for COVID-19.

Main Outcomes and Measures

The primary outcome was overall cognition, assessed by the Screen for Cognitive Impairment in Psychiatry (SCIP) and the Montreal Cognitive Assessment (MoCA). Secondary outcomes were executive function, anxiety, depressive symptoms, and neurological deficits.

Results

The study included 345 participants, including 120 patients with COVID-19 (mean [SD] age, 60.8 [14.4] years; 70 men [58.3%]), 125 hospitalized controls (mean [SD] age, 66.0 [12.0] years; 73 men [58.4%]), and 100 healthy controls (mean [SD] age, 62.9 [15.3] years; 46 men [46.0%]). Patients with COVID-19 had worse cognitive status than healthy controls (estimated mean SCIP score, 59.0 [95% CI, 56.9-61.2] vs 68.8 [95% CI, 66.2-71.5]; estimated mean MoCA score, 26.5 [95% CI, 26.0-27.0] vs 28.2 [95% CI, 27.8-28.6]), but not hospitalized controls (mean SCIP score, 61.6 [95% CI, 59.1-64.1]; mean MoCA score, 27.2 [95% CI, 26.8-27.7]). Patients with COVID-19 also performed worse than healthy controls during all other psychiatric and neurological assessments. However, except for executive dysfunction (Trail Making Test Part B; relative mean difference, 1.15 [95% CI, 1.01-1.31]), the brain health of patients with COVID-19 was not more impaired than among hospitalized control patients. These results remained consistent across various sensitivity analyses.

Conclusions and Relevance

This prospective cohort study suggests that post-COVID-19 brain health was impaired but, overall, no more than the brain health of patients from 3 non-COVID-19 cohorts of comparable disease severity. Long-term associations with brain health might not be specific to COVID-19 but associated with overall illness severity and hospitalization. This information is important for putting understandable concerns about brain health after COVID-19 into perspective.

Effects of COVID-19 on cognition and brain health

COVID-19 is associated with a range of neurological, cognitive, and mental health symptoms both acutely and chronically that can persist for many months after infection in people with long-COVID syndrome. Investigations of cognitive function and neuroimaging have begun to elucidate the nature of some of these symptoms. They reveal that, although cognitive deficits may be related to brain imaging abnormalities in some people, symptoms can also occur in the absence of objective cognitive deficits or neuroimaging changes. Furthermore, cognitive impairment may be detected even in asymptomatic individuals. We consider the evidence regarding symptoms, cognitive deficits, and neuroimaging, as well as their possible underlying mechanisms.

SARS-CoV-2 and autoantibodies in the cerebrospinal fluid of COVID-19 patients: prospective multicentre cohort study

Disease mechanisms underlying neurological and neuropsychiatric symptoms after coronavirus disease 2019 (COVID-19), termed neuro-COVID, are poorly understood. Investigations of the cerebrospinal fluid (CSF) for the presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA and antibodies, as well as autoantibodies against neuronal surface antigens, could improve our understanding in that regard. We prospectively collected CSF and blood from patients investigated by lumbar puncture for neurological or neuropsychiatric symptoms during or after COVID-19. Primary outcomes were the presence of (i) SARS-CoV-2 RNA in CSF via polymerase chain reaction (PCR), (ii) SARS-CoV-2 immunoglobulin G (IgG) anti-S receptor-binding-domain antibodies via the Euroimmun and Wantai assays and (iii) IgG autoantibodies against neuronal surface antigens using commercial cell- and tissue-based assays (Euroimmun). Secondary outcomes were (i) routine CSF investigations and (ii) correlation between SARS-CoV-2 antibody levels in CSF with serum levels, blood-brain barrier permeability and peripheral inflammation. We obtained CSF from 38 COVID-19 patients (mean age 56.5 ± 19.2 years, 53% women) who developed neurological and neuropsychiatric symptoms. CSF pleocytosis (>5 cells) was observed in 9/38 patients (23.7%), elevated CSF protein (>0.50 g/L) in 13/38 (34.2%) and elevated CSF/serum albumin ratio in 12/35 (34.3%). PCR for SARS-CoV-2 RNA in CSF was negative in all. SARS-CoV-2 CSF antibodies were detected in 15/34 (44.1%; Euroimmun assay) and 7/31 (22.6%; Wantai assay) individuals, but there were no signs of intrathecal SARS-CoV-2 IgG production. SARS-CoV-2 CSF antibodies were positively correlated with serum levels (R = 0.93, P < 0.001), blood-brain barrier permeability (R = 0.47, P = 0.006), peripheral inflammation (R = 0.51, P = 0.002) and admission to the intensive care unit [odds ratio (OR) 17.65; 95% confidence interval (CI) 1.18-264.96; P = 0.04; n = 15]. Cell-based assays detected weakly positive NMDAR, LGI1 and CASPR2 antibodies in serum of 4/34 (11.8%) patients but not in CSF. The tissue-based assay showed anti-neuronal fluorescence in CSF from one individual, staining for Purkinje cells. In summary, whereas we did not detect active SARS-CoV-2 infection in the CSF, SARS-CoV-2 antibodies were prevalent. The absence of intrathecal antibody production points towards blood-brain barrier impairment as the origin of CSF SARS-CoV-2 antibodies. In contrast, CSF autoantibodies against neuronal surface antigens were rare. There was no evidence for a clinical correlate of these antibodies. We conclude that, rather than specific autoimmune neuronal injury, non-specific effects of critical illness including an impaired blood-brain barrier are more likely to contribute to neuro-COVID.

Prevalence, pathogenesis and spectrum of neurological symptoms in COVID-19 and post-COVID-19 syndrome: a narrative review

Neurological symptoms are not uncommon during severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and reflect a broad spectrum of neurological disorders of which clinicians should be aware. The underlying pathogenesis of neurological disease in coronavirus disease 2019 (COVID-19) may be due to four mechanisms of nervous system dysfunction and injury: i) direct viral neurological invasion; ii) immune dysregulation; iii) endothelial dysfunction and coagulopathy; and iv) severe systemic COVID-19 disease. Neurological manifestations of acute COVID-19 include headache, peripheral neuropathies, seizures, encephalitis, Guillain-Barré syndrome, and cerebrovascular disease. Commonly reported long term neurological sequelae of COVID-19 are cognitive dysfunction and dysautonomia, which despite being associated with severe acute disease are also seen in people with mild disease. Assessment of cognitive dysfunction after COVID-19 is confounded by a high prevalence of comorbid fatigue, anxiety, and mood disorders. However, other markers of neuroaxonal breakdown suggest no significant neuronal injury apart from during severe acute COVID-19. The long term impact of COVID-19 on neurological diseases remains uncertain and requires ongoing vigilance.

Mental, cognitive and physical outcomes after intensive care unit treatment during the COVID-19 pandemic: a comparison between COVID-19 and non-COVID-19 patients

To compare mental, cognitive and physical outcomes between COVID-19 and non-COVID-19 patients, 3-6 months after Intensive Care Unit (ICU) treatment during the COVID-19 pandemic and to compare mental outcomes between relatives of these patients. This retrospective cohort study included 209 ICU survivors (141 COVID-19 patients and 68 non-COVID-19 patients) and 168 of their relatives (maximum one per patient) during the COVID-19 pandemic. Primary outcomes were self-reported occurrence of mental, cognitive and/or physical symptoms 3-6 months after ICU discharge. The occurrence of mental symptoms did not differ between former COVID-19 patients (34.7% [43/124]) and non-COVID-19 patients (43.5% [27/62]) (p = 0.309), neither between relatives of COVID-19 patients (37.6% [38/101]) and relatives of non-COVID-19 patients (39.6% [21/53]) (p = 0.946). Depression scores on the Hospital Anxiety and Depression Scale were lower in former COVID-19 patients, compared to non-COVID-19 patients (p = 0.025). We found no differences between COVID-19 and non-COVID-19 patients in cognitive and physical outcomes. Mental, cognitive and physical outcomes in COVID-19 ICU survivors were similar to non-COVID-19 ICU survivors. Mental symptoms in relatives of COVID-19 ICU survivors did not differ from relatives of non-COVID-19 ICU survivors, within the same time frame.

Cognitive functions in COVID-19 survivors, approaches strategies, and impact on health systems: a qualitative systematic review

Post-COVID syndrome has been defined as signs and symptoms that develop after an infection consistent with COVID-19 and continue for more than 12 weeks, including neurocognitive signs and symptoms that have an impact on the functioning and quality of life of middle-aged adult and older survivors. This systematic review describes the current knowledge of long-term cognitive impairments in COVID-19 survivors, approaches strategies, and their impact on public and private health services worldwide. The systematic review was conducted under the criteria and flowchart established in the PRISMA statement, considering studies from the PubMed, Scopus, and Web of Science databases between 2020 and 2023. The included studies considered participants over 40 years of age, COVID-19 survivors. A total of 68 articles were included, most of which had high to excellent quality. The analysis showed the presence of heterogeneous cognitive symptoms in COVID survivors, persistent for at least 12 weeks from the onset of infection, mostly unsystematized and nonspecific approaches strategies, and a lack of methods for monitoring their effectiveness, with a significant economic and logistical impact on health systems. Specific protocols are required for the rehabilitation of persistent cognitive dysfunction in COVID-19 survivors, as well as longitudinal studies to evaluate the effectiveness of these interventions.

Evaluating the Association of Montelukast Use on Neuropsychiatry-Related Healthcare Utilization and Depression in COVID-19-Hospitalized Veterans: A Nationwide VA Observational Cohort Study

BACKGROUND

Montelukast's new boxed warning for neuropsychiatric events questions its use in the setting of coronavirus disease 2019 (COVID-19) due to increased risk for new-onset psychiatric diagnoses.

OBJECTIVE

We aim to evaluate the impact of using montelukast in patients hospitalized with COVID-19 on neuropsychiatry-related healthcare utilization and depression.

METHODS

This retrospective nationwide observational cohort study using the Veterans Health Administration database included patients from January 1, 2020, through July 1, 2021. The treatment cohorts consisted of patients with and without montelukast use prior to COVID-19 hospitalization and matched using propensity score (PS) to two control cohorts: patients with COVID-19-related hospitalization without prior montelukast use and patients with prior montelukast use who were hospitalized for reasons other than COVID-19. The primary outcome of psychiatric hospitalizations at 90 days and 180 days and mental health visits at 180 days were compared using Poisson or negative binomial regression. Secondary outcomes of new-onset depression and new use of antidepressants were analyzed using multivariable logistic regression.

RESULTS

After PS matching, a total of 415 patients were included in COVID-19 with and without montelukast matched cohort and 409 patients in montelukast with and without COVID-19-related hospitalization matched cohorts. For the primary outcomes, inpatient psychiatric hospitalization at 90 days [incidence rate ratio (IRR) 95% CI 1.79 (1.36-2.36)] and 180 days [IRR 95% CI 1.79 (1.32-2.25)] and mental health visits at 180 days [IRR 95% CI 1.72 (1.45-2.03)] were significantly higher in the montelukast with COVID-19 hospitalization group compared with those hospitalized without COVID-19. No difference in primary outcomes were noted in patients hospitalized with COVID-19 with and without use of montelukast. No significant difference was found in the secondary outcomes between either comparator group.

CONCLUSIONS

Patients with prior montelukast use who were hospitalized with COVID-19 appeared to have increased rate of neuropsychiatry-related healthcare utilization.

Risks of neurological and psychiatric sequelae 2 years after hospitalisation or intensive care admission with COVID-19 compared to admissions for other causes

The association between COVID-19 and subsequent neurological and psychiatric disorders is well established. However, two important questions remain unanswered. First, what are the risks in those admitted to intensive care unit (ICU) with COVID-19? Admission to ICU is itself associated with neurological and psychiatric sequelae and it is not clear whether COVID-19 further increases those risks or changes their profile. Second, what are the trajectories of neurological and psychiatric risks in patients admitted to hospital or ICU with COVID-19, and when do the risks subside? We sought to answer these two questions using a retrospective cohort study based on electronic health records (EHR) data from the TriNetX Analytics Network (covering 89 million patients, mostly in the USA). Cohorts of patients admitted to hospital or ICU with COVID-19 were propensity score-matched (for 82 covariates capturing risk factors for COVID-19 and more severe COVID-19 illness) to patients admitted to hospital or ICU (respectively) for any other reason. Matched cohorts were followed for up to two years and the risk of 14 neurological and psychiatric outcomes were compared. A total of 280,173 patients admitted to hospital and 46,573 patients admitted to ICU with COVID-19 were successfully matched to an equal number of patients admitted to hospital or ICU for any other reason. Those hospitalised with COVID-19 were found to be at a greater risk of a range of neurological and psychiatric outcomes including seizure/epilepsy, encephalitis, myoneural junction/muscle disease, Guillain-Barré syndrome (GBS), dementia, cognitive deficits, psychotic disorder, mood and anxiety disorders, but not ischaemic stroke or intracranial haemorrhage. When risks were elevated after COVID-19, most remained so for the whole two years of follow-up (except for mood and anxiety disorders). Risk profiles and trajectories were substantially different among those admitted to ICU: compared to those admitted for any other reasons, those admitted with COVID-19 were at a greater risk of myoneural junction/muscle disease, GBS, cognitive deficits and anxiety disorder, but at a significantly lower risk of ischaemic stroke, intracranial haemorrhage, encephalitis, and mood disorder. When elevated, the risks in those admitted to ICU with COVID-19 were mostly short-lived. In summary, risks of neurological and psychiatric sequelae in patients hospitalised with COVID-19 are wide ranging and long standing whereas those in patients admitted to ICU with COVID-19 are similar to, or lower than, the risks observed post-ICU admission for any other cause. These contrasting risk trajectories are relevant for researchers, clinicians, patients, and policymakers.

COVID-19 and Risk for Mental Disorders Among Adults in Denmark

Importance

Psychiatric outcomes after COVID-19 have been of high concern during the pandemic; however, studies on a nationwide level are lacking.

Objective

To estimate the risk of mental disorders and use of psychotropic medication among individuals with COVID-19 compared with individuals not tested, individuals with SARS-CoV-2-negative test results, and those hospitalized for non-COVID-19 infections.

Design, Setting, and Participants

This nationwide cohort study used Danish registries to identify all individuals who were alive, 18 years or older, and residing in Denmark between January 1 and March 1, 2020 (N = 4 152 792), excluding individuals with a mental disorder history (n = 616 546), with follow-up until December 31, 2021.

Exposures

Results of SARS-CoV-2 polymerase chain reaction (PCR) testing (negative, positive, and never tested) and COVID-19 hospitalization.

Main Outcomes and Measures

Risk of new-onset mental disorders (International Statistical Classification of Diseases and Related Health Problems, Tenth Revision, codes F00-F99) and redeemed psychotropic medication (Anatomical Therapeutic Chemical classification codes N05-N06) was estimated through survival analysis using a Cox proportional hazards model, with a hierarchical time-varying exposure, reporting hazard rate ratios (HRR) with 95% CIs. All outcomes were adjusted for age, sex, parental history of mental illness, Charlson Comorbidity Index, educational level, income, and job status.

Results

A total of 526 749 individuals had positive test results for SARS-CoV-2 (50.2% men; mean [SD] age, 41.18 [17.06] years), while 3 124 933 had negative test results (50.6% women; mean [SD] age, 49.36 [19.00] years), and 501 110 had no tests performed (54.6% men; mean [SD] age, 60.71 [19.78] years). Follow-up time was 1.83 years for 93.4% of the population. The risk of mental disorders was increased in individuals with positive (HRR, 1.24 [95% CI, 1.17-1.31]) and negative (HRR, 1.42 [95% CI, 1.38-1.46]) test results for SARS-CoV-2 compared with those never tested. Compared with individuals with negative test results, the risk of new-onset mental disorders in SARS-CoV-2-positive individuals was lower in the group aged 18 to 29 years (HRR, 0.75 [95% CI, 0.69-0.81]), whereas individuals 70 years or older had an increased risk (HRR, 1.25 [95% CI, 1.05-1.50]). A similar pattern was seen regarding psychotropic medication use, with a decreased risk in the group aged 18 to 29 years (HRR, 0.81 [95% CI, 0.76-0.85]) and elevated risk in those 70 years or older (HRR, 1.57 [95% CI, 1.45-1.70]). The risk for new-onset mental disorders was substantially elevated in hospitalized patients with COVID-19 compared with the general population (HRR, 2.54 [95% CI, 2.06-3.14]); however, no significant difference in risk was seen when compared with hospitalization for non-COVID-19 respiratory tract infections (HRR, 1.03 [95% CI, 0.82-1.29]).

Conclusion and Relevance

In this Danish nationwide cohort study, overall risk of new-onset mental disorders in SARS-CoV-2-positive individuals did not exceed the risk among individuals with negative test results (except for those aged ≥70 years). However, when hospitalized, patients with COVID-19 had markedly increased risk compared with the general population, but comparable to risk among patients hospitalized for non-COVID-19 infections. Future studies should include even longer follow-up time and preferentially include immunological biomarkers to further investigate the impact of infection severity on postinfectious mental disorder sequelae.

Long-term neurological outcome after COVID-19 using all SARS-CoV-2 test results and hospitalisations in Denmark with 22-month follow-up

Hospitalisation with COVID-19 is associated with an increased risk of neurological sequelae; however, representative nationwide studies comparing to other infections with similar severity and also including milder SARS-CoV-2 infections have been lacking. Using the nationwide Danish registers including all SARS-CoV-2 PCR test results and hospitalisations between March 1, 2020, and December 31, 2021, we estimate the risk of any first neurological disorder diagnosed in inpatient, outpatient, or emergency room settings. We show that positive tests increase the rate of neurological disorders by a hazard ratio of 1.96 (95% confidence interval: 1.88-2.05) compared to individuals not tested and by a hazard ratio of 1.11 (95% confidence interval: 1.07-1.16) compared to individuals with negative tests only. However, there is no evidence that the risk of neurological disorders is higher for individuals who test positive compared to non-COVID-19 infections treated with anti-infective medication. The risk of neurological disorders is increased after COVID-19-hospitalisation compared to no COVID-19 hospital admission; however, these risks are comparable to hospitalisation with other respiratory infections (P value 0.328). In conclusion, COVID-19 is associated with an increased risk of neurological disorders, but no more than that observed after other infections of similar severity.

Gastrointestinal disorders in post-COVID syndrome. Clinical guidelines

Summary Post- COVID syndrome refers to the long-term consequences of a new coronavirus infection COVID-19, which includes a set of symptoms that develop or persist after COVID-19. Symptoms of gastrointestinal disorders in post- COVID syndrome, due to chronic infl ammation, the consequences of organ damage, prolonged hospitalization, social isolation, and other causes, can be persistent and require a multidisciplinary approach. The presented clinical practice guidelines consider the main preventive and therapeutic and diagnostic approaches to the management of patients with gastroenterological manifestations of postCOVID syndrome. The Guidelines were approved by the 17th National Congress of Internal Medicine and the 25th Congress of Gastroenterological Scientifi c Society of Russia.

An eye to the future: Acute and long-term neuro-ophthalmological and neurological complications of COVID-19

COVID-19 has had a significant impact on the global population and has produced compelling evidence of non-pulmonary organ dysfunction, including the nervous system. It is vital that specialists in ophthalmology and neurology are informed of the potential complications of COVID-19 and gain a deeper understanding of how COVID-19 can cause diseases of the nervous system. In this review we detail four possible mechanisms by which COVID-19 infection may result in neurological or neuro-ophthalmological complications: (1) Toxic and metabolic effects of severe pulmonary COVID-19 disease on the neural axis including hypoxia and the systemic hyper-inflammatory state, (2) endothelial dysfunction, (3) dysimmune responses directed again the neuroaxis, and (4) direct neuro-invasion and injury by the virus itself. We explore the pathological evidence for each of these and how they may link to neuro-ophthalmological disorders. Finally, we explore the evidence for long-term neurological and neuro-ophthalmological complications of COVID-19, with a focus on neurodegeneration.

Cognitive impairments among patients in a long-COVID clinic: Prevalence, pattern and relation to illness severity, work function and quality of life

BACKGROUND

A considerable proportion of people experience lingering symptoms after Coronavirus Disease 2019 (COVID-19). The aim of this study was to investigate the frequency, pattern and functional implications of cognitive impairments in patients at a long-COVID clinic who were referred after hospitalisation with COVID-19 or by their general practitioner.

METHODS

Patients underwent cognitive screening and completed questionnaires regarding subjective cognition, work function and quality of life. Patients' cognitive performance was compared with that of 150 age-, sex-, and education-matched healthy controls (HC) and with their individually expected performance calculated based on their age, sex and education.

RESULTS

In total, 194 patients were assessed, on average 7 months (standard deviation: 4) after acute COVID-19.44-53 % of the patients displayed clinically relevant cognitive impairments compared to HC and to their expected performance, respectively. Moderate to large impairments were seen in global cognition and in working memory and executive function, while mild to moderate impairments occurred in verbal fluency, verbal learning and memory. Hospitalised (n = 91) and non-hospitalised (n = 103) patients showed similar degree of cognitive impairments in analyses adjusted for age and time since illness. Patients in the cognitively impaired group were older, more often hospitalised, had a higher BMI and more frequent asthma, and were more often female. More objective cognitive impairment was associated with more subjective cognitive difficulties, poorer work function and lower quality of life.

LIMITATIONS

The study was cross-sectional, which precludes causality inferences.

CONCLUSIONS

These findings underscore the need to assess and treat cognitive impairments in patients at long-COVID clinics.

Association of cerebrospinal fluid brain-binding autoantibodies with cognitive impairment in post-COVID-19 syndrome

BACKGROUND

Neurological symptoms, in particular cognitive deficits, are common in post-COVID-19 syndrome (PCS). There is no approved therapy available, and the underlying disease mechanisms are largely unknown. Besides others, autoimmune processes may play a key role.

DESIGN

We here present data of a prospective study conducted between September 2020 and December 2021 and performed at two German University hospitals with specialized Neurology outpatient clinics. Fifty patients with self-reported cognitive deficits as main complaint of PCS and available serum and CSF samples were included. Cell-based assays and indirect immunofluorescence on murine brain sections were used to detect autoantibodies against intracellular and surface antigens in serum and CSF and analyzed for associations with cognitive screening assessment.

RESULTS

Clearly abnormal cognitive status (MoCA ≤ 25/30 points) was only seen in 18/50 patients with self-reported cognitive deficits. Most patients (46/50) had normal routine CSF parameters. anti-neuronal autoantibodies were found in 52 % of all patients: n = 9 in serum only, n = 3 in CSF only and n = 14 in both, including those against myelin, Yo, Ma2/Ta, GAD65 and NMDA receptor, but also a variety of undetermined epitopes on brain sections. These included cerebral vessel endothelium, Purkinje neurons, granule cells, axon initial segments, astrocytic proteins and neuropil of basal ganglia or hippocampus as well as a formerly unknown perinuclear rim pattern. Pathological MoCA results were associated with the presence of anti-neuronal antibodies in CSF (p = 0.0004).

CONCLUSIONS

Autoantibodies targeting brain epitopes are common in PCS patients and strongly associate with pathological cognitive screening tests, in particular when found in CSF. Several underlying autoantigens still await experimental identification. Further research is needed to inform on the clinical relevance of these autoantibodies, including controlled studies that explore the potential efficacy of antibody-depleting immunotherapy in PCS.

Associations of subjective and objective cognitive functioning after COVID-19: A six-month follow-up of ICU, ward, and home-isolated patients

Background

Subjective and objective cognitive dysfunction are reported after COVID-19 but with limited data on their congruence and associations with the severity of the acute disease. The aim of this cohort study is to describe the prevalence of subjective and objective cognitive dysfunction at three and six months after COVID-19 and the associations of subjective cognitive symptoms and psychological and disease-related factors.

Methods

We assessed a cohort of 184 patients at three and six months after COVID-19: 82 patients admitted to the Intensive Care Unit (ICU), 53 admitted to regular hospital wards, and 49 isolated at home. A non-COVID control group of 53 individuals was included. Demographic and clinical data were collected. Subjective cognitive symptoms, objective cognitive impairment, and depressive and post-traumatic stress disorder (PTSD) symptoms were assessed.

Results

At six months, subjective cognitive impairment was reported by 32.3% of ICU-treated, 37.3% of ward-treated, and 33.3% of home-isolated patients and objective cognitive impairment was observed in 36.1% of ICU-treated, 34.7% of ward-treated, and 8.9% of home-isolated patients. Subjective cognitive symptoms were associated with depressive and PTSD symptoms and female sex, but not with objective cognitive assessment or hospital metrics.

Conclusions

One-third of COVID-19 patients, regardless of the acute disease severity, reported high levels of subjective cognitive dysfunction which was not associated with results from objective cognitive screening but with psychological and demographic factors. Our study stresses the importance of thorough assessment of patients reporting long-term subjective symptoms, screening for underlying mental health related factors such as PTSD or depression.

Long term neuropsychiatric consequences in COVID-19 survivors: Cognitive impairment and inflammatory underpinnings fifteen months after discharge

BACKGROUND

Emerging evidence shows that cognitive dysfunction may occur following coronavirus disease 19 (COVID-19) infection which is one of the most common symptoms reported in researches of "Long COVID". Several inflammatory markers are known to be elevated in COVID-19 survivors and the relationship between long-term inflammation changes and cognitive function remains unknown.

METHODS

We assessed cognitive function and neuropsychiatric symptoms of 66 COVID-19 survivors and 79 healthy controls (HCs) matched with sex, age, and education level using a digital, gamified cognitive function evaluation tool and questionnaires at 15 months after discharge. Venous blood samples were collected to measure cytokine levels. We performed correlation analyses and multiple linear regression analysis to identify the factors potentially related to cognitive function.

RESULTS

The COVID-19 survivors performed less well on the Trails (p = 0.047) than the HCs, but most of them did not report subjective neuropsychiatric symptoms. Intensive care unit experience (β = -2.247, p < 0.0001) and self-perceived disease severity (β = -1.522, p = 0.007) were positively correlated, whereas years of education (β = 0.098, p = 0.013) was negatively associated with the performance on the Trails. Moreover, the abnormally elevated TNF-α levels (r = -0.19, p = 0.040) were negatively correlated with performance on the Trails in COVID-19 group.

CONCLUSION

Our findings suggest that COVID-19 survivors show long-term cognitive impairment in executive function, even at 15 months after discharge. Serum TNF-α levels may be an underlying mechanism of long-term cognitive impairment in patients recovering from COVID-19.

Co-Occurring Catatonia and COVID-19 Diagnoses Among Hospitalized Individuals in 2020: A National Inpatient Sample Analysis

BACKGROUND

COVID-19 is associated with a range of neuropsychiatric manifestations. While case reports and case series have reported catatonia in the setting of COVID-19 infection, its rate has been poorly characterized.

OBJECTIVE

This study reports the co-occurrence of catatonia and COVID-19 diagnoses among acute care hospital discharges in the United States in 2020.

METHODS

The National Inpatient Sample, an all-payors database of acute care hospital discharges, was queried for patients of any age discharged with a diagnosis of catatonia and COVID-19 in 2020.

RESULTS

Among 32,355,827 hospitalizations in the 2020 National Inpatient Sample, an estimated 15,965 (95% confidence interval: 14,992-16,938) involved a diagnosis of catatonia without COVID-19 infection, 1,678,385 (95% confidence interval: 1,644,738-1,712,022) involved a diagnosis of COVID-19 without a co-occurring catatonia diagnosis, and 610 (95% confidence interval: 578-642) involved both catatonia and COVID-19 infection. In an adjusted model, a diagnosis of COVID-19, but not a diagnosis of catatonia or the combination of catatonia and COVID-19, was associated with increased mortality. Patients with catatonia and COVID-19 were frequently diagnosed with encephalopathy and delirium codes.

CONCLUSIONS

Catatonia and COVID-19 were rarely co-diagnosed in 2020, and catatonia diagnosis was not associated with increased mortality in patients with COVID-19. Further research is needed to better characterize the phenomenology of catatonia in the setting of COVID-19 infection and its optimal treatment.

Cerebral Metabolic Rate of Glucose and Cognitive Tests in Long COVID Patients

BACKGROUND

Common long-term sequelae after COVID-19 include fatigue and cognitive impairment. Although symptoms interfere with daily living, the underlying pathology is largely unknown. Previous studies report relative hypometabolism in frontal, limbic and cerebellar regions suggesting focal brain involvement. We aimed to determine whether absolute hypometabolism was present and correlated to same day standardized neurocognitive testing.

METHODS

Fourteen patients included from a long COVID clinic had cognitive testing and quantitative dynamic [¹⁸F]FDG PET of the brain on the same day to correlate cognitive function to metabolic glucose rate.

RESULTS

We found no hypometabolism in frontal, limbic and cerebellar regions in cognitively impaired relative to cognitive intact patients. In contrast, the cognitive impaired patients showed higher cerebellar metabolism (p = 0.03), which correlated with more severe deficits in working memory and executive function (p = 0.03).

CONCLUSIONS

Hypermetabolism in the cerebellum may reflect inefficient brain processing and play a role in cognitive impairments after COVID-19.

Neurological manifestations of post-COVID-19 syndrome S1-guideline of the German society of neurology

Infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) leads to COVID-19 (COrona VIrus Disease-2019). SARS-CoV-2 acute infection may be associated with an increased incidence of neurological manifestations such as encephalopathy and encephalomyelitis, ischemic stroke and intracerebral hemorrhage, anosmia and neuromuscular diseases. Neurological manifestations are commonly reported during the post-acute phase and are also present in Long-COVID (LCS) and post-COVID-19 syndrome (PCS). In October 2020, the German Society of Neurology (DGN, Deutsche Gesellschaft für Neurologie) published the first guideline on the neurological manifestations of COVID-19. In December 2021 this S1 guideline was revised and guidance for the care of patients with post-COVID-19 syndrome regarding neurological manifestations was added. This is an abbreviated version of the post-COVID-19 syndrome chapter of the guideline issued by the German Neurological society and published in the Guideline repository of the AWMF (Working Group of Scientific Medical Societies; Arbeitsgemeinschaft wissenschaftlicher Medizinischer Fachgesellschaften).

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.

Cognitive Assessment in SARS-CoV-2 Patients: A Systematic Review

Background

Patients with post-infective severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) often show both short- and long-term cognitive deficits within the dysexecutive/inattentive spectrum. However, little is known about which cognitive alterations are commonly found in patients recovered from SARS-CoV-2, and which psychometric tools clinicians should consider when assessing cognition in this population. The present work reviewed published studies to provide a critical narrative of neuropsychological (NPs) deficits commonly observed after SARS-CoV-2 infection and the tests most suited for detecting such cognitive sequelae depending on illness severity.

Methods

This review followed the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines and was pre-registered on Prospective Register of Systematic Reviews (PROSPERO) (CRD42021253079). Observational studies quantitatively assessing cognition in patients with post-infective SARS-CoV-2 were considered. From 711 retrieved articles, 19 studies conducted on patients with SARS-CoV-2 without medical comorbidities were included and stratified by disease severity.

Results

The majority of studies (N = 13) adopted first-level tests. The most frequently administered screeners were the Montreal Cognitive Assessment (MoCA) and the Mini-Mental State Examination (MMSE)—with the former more likely to detect mild, and the latter moderate/severe deficits. Among second-level tests, those assessing attention and executive functions (EFs) were highly represented. Remotely-delivered tests yielded lower percentages of cognitive impairment. Overall, cognitive domains often found to be impaired were EFs, attention, and memory.

Conclusion

Cognitive sequelae in patients with post-infective SARS-CoV-2 can be detected with NPs testing. Depending on the psychometric test features, the likelihood of observing cognitive deficits can vary. Further studies on larger sample sizes are needed to investigate the clinical usefulness of second-level tools. The primary goal of preventative health services should be the early detection and intervention of emerging cognitive deficits.

[Postcovid cognitive impairment]

This review addresses current issues in post-COVID syndrome with a focus on neurocognitive impairment. The results of studies on complications in patients of different ages and health statuses recovered from mild to severe COVID-19 are discussed. Current data on the pathogenetic mechanisms of the development of various post-COVID disorders are presented, including a detailed discussion of central nervous system damage. The paper summarizes data on the relationship between neurocognitive disorders and accelerated cell aging, chronic nonspecific inflammation, and reduced neuroplasticity in the central nervous system. The main pathogenetic ways to prevent COVID-related complications, including neuronal tissue damage and the prospects for managing such patients are discussed. The choice of pathogenetic therapy in patients with neurocognitive impairment in the post-COVID period is assessed. The main benefits of choline alfoscerate therapy for neurocognitive impairment in patients with post-COVID syndrome are discussed.

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.