Neurological manifestations as the predictors of severity and mortality in hospitalized individuals with COVID-19: a multicenter prospective clinical study

Complexity and Diversity of the Neurological Spectrum of SARS-CoV-2 over Three Waves of COVID-19

Background/Objectives: SARS-CoV-2 continually mutates, with five identified variants. Many neurological manifestations were observed during the COVID-19 pandemic, with differences between virus variants. The aim of this study is to assess the frequency and characteristics of neurological manifestations during COVID-19 in hospitalized patients over three waves in Poland with comparison and analysis correlation with the course of infection. Methods: This retrospective single-center study included 600 consecutive adults with confirmed COVID-19, hospitalized during 3 waves (pre-Delta, Delta and Omicron) in Poland. Demographic and clinical information and neurological manifestations were collected and compared across three periods. Results: The median age of the study group was 68, lower during the Delta wave. In the Omicron period, the disease severity at admission and inflammatory markers concentration were the lowest. Neurological manifestations were observed in 49%. The most common were altered mentation, headache, myalgia, mood disorder, ischemic stroke and encephalopathy. Smell and taste disturbances (STDs) were less frequent in the Omicron period. Neurological complications were predominant in the pre-Delta and Omicron periods. Ischemic stroke was observed more often in pre-Delta period. Altered mentation was related to higher severity at admission, worse lab test results, higher admission to ICU and mortality, while headache reduced mortality. Pre-existing dementia was related to higher mortality. Conclusions: Neurological manifestations of COVID-19 are frequent, with a lower rate of STDs in the Omicron period and more often cerebrovascular diseases in the pre-Delta period. Headache improves the course of COVID-19, while altered mentation, stroke and neurological comorbidities increase severity and mortality.

Headache Associated with Coronavirus Disease 2019

Headache affects around half of patients in the acute phase of COVID-19 and generally occurs at the beginning of the symptomatic phase, has an insidious onset, and is bilateral, and of moderate to severe intensity. COVID-19 may also present complications that cause acute and persistent headaches, such as cerebrovascular diseases, rhinosinusitis, meningitis, and intracranial hypertension. In 10% to 20% of patients with COVID-19, headache may persist beyond the acute phase. In general, the headache improves over time. To date, there are no clinical trials that have assessed the treatment of persistent post-COVID-19 headache.

Guillain-Barré syndrome and SARS-CoV-2 infection: a systematic review and meta-analysis on a debated issue and evidence for the 'Italian factor'

BACKGROUND AND PURPOSE

The association between Guillain-Barré syndrome (GBS) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is debated. This study reappraises, after three pandemic years, the epidemiological data and the features of GBS in SARS-CoV-2 patients.

METHODS

A systematic review and meta-analysis of case reports/series and cohort studies published between 1 January 2020 and 19 April 2023 was performed.

RESULTS

In all, 209 case reports/series (304 patients) and 26 cohort studies were included. The risk of GBS in northern Italy during the first pandemic wave was 2.85 times increased (95% confidence interval [CI] 1.54; 5.25) whereas in some countries the risk during the first pandemic year was 0.17 times reduced (risk ratio 0.83, 95% CI 0.75; 0.93). The incidence of GBS in SARS-CoV-2 Italian hospitalized cohorts was 8.55 per 1000 (95% CI 5.33; 12.49) with an estimated incidence of 0.13 GBS per 1000 in the SARS-CoV-2 infected population. In European cohorts the pooled rate of GBS with SARS-CoV-2 infection was 61.3% of the total. GBS patients with SARS-CoV-2 infection showed more frequently, but not differently from non-infected patients, the classical clinical presentation and the demyelinating subtype. Cranial nerves were more frequently involved in SARS-CoV-2 infected patients.

CONCLUSIONS

An increased risk of GBS occurred in northern Italy during early COVID-19 pandemic. The recognition of the 'Italian factor' reconciles contrasting results of the epidemiological studies. The slightly reduced GBS risk in other countries and the relatively high frequency of GBS associated with SARS-CoV-2 infection can be explained by the adopted health measures that decreased the circulation of other GBS infective antecedents.

Neurotropism of SARS-CoV-2: A Pathological Examination of Neurosurgical Specimens

BACKGROUND AND OBJECTIVES

Neurological manifestations may occur in more than 80% of patients hospitalized with COVID-19 infection, including severe disruptions of the central nervous system (CNS), such as strokes, encephalitis, or seizures. Although the primary pathophysiological mechanism for the effects of COVID-19 in CNS remains unknown, evidence exists for both direct injury from neuroinvasion and indirect effects from disruptions in systemic inflammatory and coagulation pathways. In this study, we analyzed CNS tissue from living patients to better understand these processes.

METHODS

With institutional review board approval and patient consent, samples that would be otherwise discarded from patients with active or recent (within 6 days of surgery) COVID-19 infection undergoing neurosurgical intervention were collected and tested for the presence of SARS-CoV-2 using immunohistochemistry, in situ hybridization, electron microscopy, and reverse transcription polymerase chain reaction.

RESULTS

Five patients with perioperative mild-to-moderate COVID-19 infection met inclusion criteria (2 male, 3 female; mean age 38.8 ± 13.5 years). Neurosurgical diagnoses included a glioblastoma, a ruptured arteriovenous malformation, a ruptured posterior inferior cerebellar artery aneurysm, a middle cerebral artery occlusion, and a hemorrhagic pontine cavernous malformation. Samples analyzed included the frontal lobe cortex, olfactory nerve, arteriovenous malformation/temporal lobe parenchyma, middle cerebral artery, cerebellum, and cavernous malformation/brainstem parenchyma. Testing for the presence of SARS-CoV-2 was negative in all samples.

CONCLUSION

The CNS is likely not a significant viral reservoir during mild-to-moderate COVID-19 infection, although direct neuroinvasion is not definitively excluded. Additional testing to help elucidate the relative contributions of direct and indirect pathways for CNS injury from COVID is warranted.

New Onset Seizures in Hospitalized COVID-19 Patients; A Systematic Review and Meta-Analysis

Objective

Seizures in COVID-19 patients continue to be a common reason for consulting the neurology service in the inpatient setting. This paper assesses the frequency of new onset seizures in adult hospitalized COVID-19 patients.

Method

PubMed and EMBASE were searched, with fifteen cohort studies identified to calculate the primary outcome, which was the frequency of new onset seizures in hospitalized COVID-19 patients. An inverse variance meta-analysis of single proportions with a random effects model was applied to these cohort studies to calculate the primary outcome. Risk of bias in individual studies was assessed using the 10-item risk of bias tool for prevalence studies.

Results

The meta-analysis revealed a frequency of .71% (95% confidential interval: .32-1.25, I2 = 89%, 147/28242 patients) for acute symptomatic seizures in patients with COVID-19. For secondary outcomes, the risk of seizures in patients who had EEG completed was 8.49% (95% confidential interval: .62-24.07, I2 = 14%, 44/535 patients). Slightly less than half of patients with COVID-19 and seizures were reported to have acute imaging abnormalities (45.7%) with acute vascular insults being commonly reported. Only a small percentage of COVID-19 patients with seizures (2.8%) met the criteria for COVID-19 encephalitis as determined by the international encephalitis consortium.

Conclusion

The frequency of seizures in COVID-19 was .71% (95% confidential interval: .32-1.25). Slightly less than half of COVID-19 patients had head imaging abnormalities as a complication of COVID-19 infection. Only a small percentage of patients with seizures and COVID-19 met the criteria for COVID-19 encephalitis.

Mental Healthcare in Pediatrics During the COVID-19 Pandemic: A Call for International Public Health Action

Public health measures associated with coronavirus disease 2019 (COVID-19), such as lockdowns and quarantine of suspected cases, can negatively affect children's mental health status. Although the current crisis provides personal growth and family cohesion opportunities, pitfalls appear to outweigh the benefits. The magnitude and quality of its impact on children depend on several factors, including anxiety, lack of social contact, and a reduced opportunity for stress regulation, along with an increased risk for parental mental health issues, child maltreatment, and domestic violence. Children with special needs and social disadvantages like trauma experiences, disabilities, pre-existing mental illness, e.g., autism spectrum disorders and hyperactivity, and low socioeconomic status, may be at higher risk in this context. Here, the potentials social support can provide for pediatrics, both healthy children and children with special needs, are reviewed after an overview of quarantine's adverse effects on this special population during a pandemic. The most common psychological issues associated with the COVID-19 pandemic are sleep disorders, mood swings, depression, anxiety, decreased attention, stress, irritability, anger, and fear. Moreover, the impact of COVID-19 on children's physical health includes weight gain, reduced physical activity, immune dysregulation, and cardiometabolic disorders. All support systems, involving parents, teachers/school counselors, pediatricians, mental healthcare workers, and Health and Art (HEART) groups, need to enter the scene and make their share of children's mental health care.

Neurological involvement in hospitalized children with SARS-CoV-2 infection: a multinational study

BACKGROUND AND OBJECTIVES

Neurological involvement associated with SARS-CoV-2 infection is increasingly recognized. However, the specific characteristics and prevalence in pediatric patients remain unclear. The objective of this study was to describe the neurological involvement in a multinational cohort of hospitalized pediatric patients with SARS-CoV-2.

METHODS

This was a multicenter observational study of children <18 years of age with confirmed SARS-CoV-2 infection or multisystemic inflammatory syndrome (MIS-C) and laboratory evidence of SARS-CoV-2 infection in children, admitted to 15 tertiary hospitals/healthcare centers in Canada, Costa Rica, and Iran February 2020-May 2021. Descriptive statistical analyses were performed and logistic regression was used to identify factors associated with neurological involvement.

RESULTS

One-hundred forty-seven (21%) of 697 hospitalized children with SARS-CoV-2 infection had neurological signs/symptoms. Headache (n = 103), encephalopathy (n = 28), and seizures (n = 30) were the most reported. Neurological signs/symptoms were significantly associated with ICU admission (OR: 1.71, 95% CI: 1.15-2.55; p = 0.008), satisfaction of MIS-C criteria (OR: 3.71, 95% CI: 2.46-5.59; p < 0.001), fever during hospitalization (OR: 2.15, 95% CI: 1.46-3.15; p < 0.001), and gastrointestinal involvement (OR: 2.31, 95% CI: 1.58-3.40; p < 0.001). Non-headache neurological manifestations were significantly associated with ICU admission (OR: 1.92, 95% CI: 1.08-3.42; p = 0.026), underlying neurological disorders (OR: 2.98, 95% CI: 1.49-5.97, p = 0.002), and a history of fever prior to hospital admission (OR: 2.76, 95% CI: 1.58-4.82; p < 0.001).

DISCUSSION

In this study, approximately 21% of hospitalized children with SARS-CoV-2 infection had neurological signs/symptoms. Future studies should focus on pathogenesis and long-term outcomes in these children.

Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease and COVID-19: A Systematic Review

Background

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is an uncommon neurological disease affecting the central nervous system (CNS). Numerous neurological disorders, including multiple sclerosis (MS), neuromyelitis optica spectrum disorder (NMOSD), acute transverse myelitis (ATM), and MOGAD, have been reported following the COVID-19 infection during the current COVID-19 pandemic. On the other hand, it has been suggested that patients with MOGAD may be at greater risk for infection (particularly in the current pandemic).

Objective

In this systematic review, we gathered separately 1) MOGAD cases following COVID-19 infection as well as 2) clinical course of patients with MOGAD infected with COVID-19 based on case reports/series.

Methods

329 articles were collected from 4 databases. These articles were conducted from inception to March 1st, 2022.

Results

Following the screening, exclusion criteria were followed and eventually, 22 studies were included. In 18 studies, a mean ± SD time interval of 18.6 ± 14.9 days was observed between infection with COVID-19 and the onset of MOGAD symptoms. Symptoms were partially or completely recovered in a mean of 67 days of follow-up. Among 4 studies on MOGAD patients, the hospitalization rate was 25%, and 15% of patients were hospitalized in the intensive care unit (ICU).

Conclusion

Our systematic review demonstrated that following COVID-19 infection, there is a rare possibility of contracting MOGAD. Moreover, there is no clear consensus on the susceptibility of MOGAD patients to severe COVID-19. However, obtaining deterministic results requires studies with a larger sample size.

Development and Validation of the Parosmia Olfactory Dysfunction Outcomes Rating (DisODOR)

OBJECTIVE

Develop and validate a quality-of-life (QoL) outcome measure for patients with dysosmia.

STUDY DESIGN

Cross-sectional survey study.

SETTING

Otolaryngology clinics, research registries, and Facebook support groups.

METHODS

A 59-item pilot survey with questions addressing parosmia concerns was developed using input from subjects with parosmia and clinical expertise from Otolaryngologists. After item reduction, the Parosmia Olfactory Dysfunction Outcomes Rating (DisODOR) was reduced to its final 29 items. DisODOR maximum score is 116 (each item score 0-4) with higher scores indicating a higher degree of dysfunction from smell distortion. DisODOR was validated using participants with parosmia persisting >3 months after severe acute respiratory syndrome coronavirus 2 (cases) and healthy controls. Reliability, face and content validity, internal consistency, convergent validity, discriminative validity, sensitivity to change, and the minimal clinically important difference (MCID) were assessed.

RESULTS

A total of 134 cases and 20 controls completed DisODOR. The mean (SD) age was 45.9 (12.2) for cases and 29.6 (8.9) for controls. The mean score difference between cases and controls was 45.0 (95% confidence interval, 40.5-49.5) displaying good discriminative validity. DisODOR showed strong test-retest reliability (r = .942) with high internal consistency (Cronbach's α = .971). DisODOR had a moderate correlation with SNOT-22 scores (r = .619) indicating good convergent validity. There is an excellent association with the global impression of severity categories (η2  = 0.447). Based on the distribution method, the MCID is 15.

CONCLUSION

DisODOR is a valid, reliable QoL instrument for parosmia that can be used to measure the functional impact and QoL impairment for parosmia patients. DisODOR is sensitive to change and thus can be used in studies investigating treatments for parosmia.

Clinical characteristics of 365 hospitalized COVID-19 patients with neurological symptoms: an observational study

OBJECTIVE

Since the beginning of the COVID-19 pandemic, a number of COVID-related neurological manifestations have been reported. We aimed to categorize the features of hospitalized COVID-19 patients who experienced neurological symptoms.

METHODS

In this descriptive, cross-sectional study, we enrolled all patients hospitalized with COVID-19 who experienced neurological symptoms in two hospitals in Tehran. Diagnosis of COVID-19 was established by PCR tests or computed tomography of the chest combined with COVID-19 clinical findings. The clinical characteristics, laboratory data, and imaging findings from 365 patients were analyzed.

RESULTS

The average patient age was 59.2 ± 16.7 years and included 213 males and 152 females. The most prevalent neurological symptoms were headache (56.2%), impaired consciousness (55%), and dizziness (20.5%). During hospitalization, most of the patients did not require mechanical ventilation (81.9%). The percentage of patients with end-organ damage was 9% and mortality was 15%. Regression analysis on the neurological symptoms indicated that the mortality rate of patients with headaches was 84% lower than for the other neurological symptoms. Hyperglycemia was significantly related with end-organ damage and mortality (p = 0.029, p = 0.08, respectively). New vascular lesions were evident on brain MRIs of 9 patients and brain CTs of 16 patients.

CONCLUSION

Among the neurological symptoms of patients with COVID-19, headache appeared to indicate a protective factor against development of end-organ damage as well as mortality.

Neuroimaging Spectrum in COVID-19 Infection: A Single-Center Experience

Background and Purpose  The ongoing coronavirus disease 2019 (COVID-19) pandemic is a multisystemic disease and involvement of the nervous system is well established. The neurological and neuroimaging features of the disease have been extensively evaluated. Our study aimed to elucidate the neuroradiological findings in COVID-19 infected patients admitted to our institute during the first and second waves of the pandemic in India. Methods  This was a single-center retrospective study of all COVID-19 positive patients who underwent neuroimaging between March 2020 and May 2021. The presenting neurological complaints, the imaging findings in computed tomography (CT) imaging, and/or magnetic resonance imaging (MRI) were recorded. They recorded the findings in the subheadings of ischemic stroke, hemorrhagic stroke, parainfectious demyelination, acute encephalitis syndrome, and changes of global hypoxic changes. Patients with age-related, chronic, and incidental findings were excluded. Results  The study comprised of 180 COVID-19 positive patients who underwent neuroimaging. CT scan was performed for 169 patients, MRI for 28, and a combination of both CT and MRI was performed for 17 patients. Seventy percent of patients were males, and median age was 61.5 years (interquartile range: 48.25-70.75). Out of the 180 patients, 66 patients had nonspecific findings that could not be attributed to COVID-19 infection. In the remaining 114 patients, 77 (42.7%) had ischemic findings, while 22 (12.2%) had hemorrhagic stroke. Hypoxic ischemic changes were noted in five patients. The rest of the patients had a spectrum of changes including, cerebellitis (3), tumefactive demyelination (1), COVID-19-associated encephalitis (1), hemorrhagic acute demyelinating encephalomyelitis (1), transverse myelitis (1), cytotoxic lesions of corpus callosum (1), Guillain-Barre syndrome (1), and COVID-19-associated microhemorrhages (1). Conclusion  Neurological manifestations of COVID-19 infection are not uncommon, and our understanding of this topic is expanding. A complex interplay of neurotropism and direct central nervous system invasion, immune activation and cytokine storm, vasculitis, and parainfectious processes are implicated in the pathophysiology. While the most common imaging finding was ischemic stroke, followed by hemorrhagic stroke, a diverse range of parainfectious findings was also noted in our study.

SARS-CoV-2 airway infection results in the development of somatosensory abnormalities in a hamster model

Although largely confined to the airways, SARS-CoV-2 infection has been associated with sensory abnormalities that manifest in both acute and chronic phenotypes. To gain insight on the molecular basis of these sensory abnormalities, we used the golden hamster model to characterize and compare the effects of infection with SARS-CoV-2 and influenza A virus (IAV) on the sensory nervous system. We detected SARS-CoV-2 transcripts but no infectious material in the cervical and thoracic spinal cord and dorsal root ganglia (DRGs) within the first 24 hours of intranasal virus infection. SARS-CoV-2-infected hamsters exhibited mechanical hypersensitivity that was milder but prolonged compared with that observed in IAV-infected hamsters. RNA sequencing analysis of thoracic DRGs 1 to 4 days after infection suggested perturbations in predominantly neuronal signaling in SARS-CoV-2-infected animals as opposed to type I interferon signaling in IAV-infected animals. Later, 31 days after infection, a neuropathic transcriptome emerged in thoracic DRGs from SARS-CoV-2-infected animals, which coincided with SARS-CoV-2-specific mechanical hypersensitivity. These data revealed potential targets for pain management, including the RNA binding protein ILF3, which was validated in murine pain models. This work elucidates transcriptomic signatures in the DRGs triggered by SARS-CoV-2 that may underlie both short- and long-term sensory abnormalities.

Neurological Manifestations of Coronavirus Disease 2019 in Hospitalized Patients: A Lebanese Cohort Study

BACKGROUND

Concerns regarding potential neurologic complications of COVID-19 are being increasingly reported worldwide. Our objective was to investigate the neurologic complications of COVID-19 among a cohort of Lebanese patients with SARS-CoV-2 infection admitted to Rafik Hariri University Hospital (RHUH), the leading COVID-19 testing and treatment center in Lebanon.

METHODS

This is a retrospective, single-center, observational study conducted from March to July 2020 at RHUH, Lebanon.

RESULTS

Of 169 hospitalized patients with confirmed SARS-CoV-2 infection (mean {SD} age was 45.75 {19} years and 62.7% were men), 91 patients (53.8%) had severe infection and 78 patients (46.2%) had non-severe infection according to the American Thoracic Society guidelines for community-acquired pneumonia. Overall, 112 patients (66.3%) developed neurologic symptoms: CNS (46.1%), PNS (43.7%), and skeletal muscle injury (2.4%). Compared with patients with non-severe infection, patients with severe infection were significantly older, were male and more likely to have underlying disorders, especially diabetes and cardiac or cerebrovascular disease. Moreover, those patients experienced more typical COVID-19 symptoms at onset of illness such as fever, cough and fatigue. However, there was no significant difference in the frequency of all nervous system manifestations between the severe and the non-severe infection groups (57 {62.6%} vs 55 {70.5%}; p =0.316), except for impaired consciousness, where seven patients had impaired consciousness in the severe group compared to none in the non-severe group (p=0.012).

CONCLUSION

A wide variety of neurologic symptoms were detected in our Lebanese cohort of hospitalized COVID-19 patients. A comprehensive knowledge of the neurologic manifestations will help healthcare providers to be more attentive to these complications.

Neurological symptoms and comorbidity profile of hospitalized patients with COVID-19

BACKGROUND

 The neurological manifestations in COVID-19 adversely impact acute illness and post-disease quality of life. Limited data exist regarding the association of neurological symptoms and comorbid individuals.

OBJECTIVE

 To assess neurological symptoms in hospitalized patients with acute COVID-19 and multicomorbidities.

METHODS

 Between June 2020 and July 2020, inpatients aged 18 or older, with laboratory-confirmed COVID-19, admitted to the Hospital São Paulo (Federal University of São Paulo), a tertiary referral center for high complexity cases, were questioned about neurological symptoms. The Composite Autonomic Symptom Score 31 (COMPASS-31) questionnaire was used. The data were analyzed as a whole and whether subjective olfactory dysfunction was present or not.

RESULTS

 The mean age of the sample was 55 ± 15.12 years, and 58 patients were male. The neurological symptoms were mostly xerostomia (71%), ageusia/hypogeusia (50%), orthostatic intolerance (49%), anosmia/hyposmia (44%), myalgia (31%), dizziness (24%), xerophthalmia (20%), impaired consciousness (18%), and headache (16%). Furthermore, 91% of the patients had a premorbidity. The 44 patients with subjective olfactory dysfunction were more likely to have hypertension, diabetes, weakness, shortness of breath, ageusia/hypogeusia, dizziness, orthostatic intolerance, and xerophthalmia. The COMPASS-31 score was higher than that of previously published controls (14.85 ± 12.06 vs. 8.9 ± 8.7). The frequency of orthostatic intolerance was 49% in sample and 63.6% in those with subjective olfactory dysfunction (2.9-fold higher risk compared to those without).

CONCLUSION

 A total of 80% of inpatients with multimorbidity and acute COVID-19 had neurological symptoms. Chemical sense and autonomic symptoms stood out. Orthostatic intolerance occurred in around two-thirds of the patients with anosmia/hyposmia. Hypertension and diabetes were common, mainly in those with anosmia/hyposmia.

Olfactory disorders in COVID-19 patients as a prognostic factor: a systematic review

Background

The reduction, loss, or impaired sense of smell and taste is common in patients with COVID-19. We aimed to investigate olfactory disorders (ODs) in patients with COVID-19 as a prognostic factor.

Methods

In this systematic review and meta-analysis, studies that assessed ODs in patients with COVID-19 were included. International databases, including PubMed, Embase, MEDLINE, Web of Science, and Scopus, were searched up to 20 March 2021. The random-effects model was used to combine the results of studies. Results were reported with a 95% confidence interval.

Results

In this study, out of 724 references, ten studies had the inclusion criteria. The odds of death in patients with the OD were 69% lower than in those without the ODs (OR = 0.31, 95% CI: 0.14, 0.69), and OD increased the odds of positive polymerase chain reaction (PCR) test (OR = 13.34, 95% CI: 4.2, 42.37).

Conclusions

The findings of our study showed that OD had an inverse and significant relationship with death in COVID-19 patients, and the patients with OD seemed to have a lower risk of mortality.

Qualitative Olfactory Dysfunction and COVID-19: An Evidence-Based Review with Recommendations for the Clinician

BACKGROUND

Nearly 40% of patients who experience smell loss during SARS-CoV-2 infection may develop qualitative olfactory dysfunction, most commonly parosmia. Our evidence-based review summarizes the evolving literature and offers recommendations for the clinician on the management of patients experiencing parosmia associated with COVID-19.

METHODS

We performed a systematic search using independent queries in PubMed, Embase, Ovid, and Cochrane databases, then categorized articles according to themes that emerged regarding epidemiology, effect on quality of life, disease progression, prognosis, pathophysiology, diagnosis, and treatment of parosmia.

RESULTS

We identified 123 unique references meeting eligibility and performed title and abstract review with 2 independent reviewers, with 74 articles undergoing full-text review. An inductive approach to thematic development provided 7 central themes regarding qualitative olfactory dysfunction following COVID-19.

CONCLUSIONS

While other respiratory viruses are known to cause qualitative olfactory disturbances, the incidence of parosmia following COVID-19 is notable, and correlates negatively with age. The presence of parosmia predicts persistent quantitative olfactory dysfunction. Onset can occur months after infection, and symptoms may persist for well over 7 months. Affected patients report increased anxiety and decreased quality of life. Structured olfactory training with essential oils is the preferred treatment, where parosmia predicts recovery of aspects of quantitative smell loss when undergoing training. There is limited evidence that nasal corticosteroids may accelerate recovery of olfactory function. Patients should be prepared for the possibility that symptoms may persist for years, and providers should guide them to resources for coping with their psychosocial burden.

Headache attributed to SARS-CoV-2 infection, vaccination and the impact on primary headache disorders of the COVID-19 pandemic: A comprehensive review

OBJECTIVE

The objective is to summarize the knowledge on the epidemiology, pathophysiology and management of secondary headache attributed to SARS-CoV-2 infection and vaccination; as well as to delineate their impact on primary headache disorders.

METHODS

This is a narrative review of the literature regarding primary and secondary headache disorders in the setting of COVID-19 pandemic. We conducted a literature search in 2022 on PubMed, with the keywords "COVID 19" or "vaccine" and "headache" to assess the appropriateness of all published articles for their inclusion in the review.

RESULTS

Headache is a common and sometimes difficult-to-treat symptom of both the acute and post-acute phase of SARS-CoV-2 infection. Different pathophysiological mechanisms may be involved, with the trigeminovascular system as a plausible target. Specific evidence-based effective therapeutic options are lacking at present. Headache attributed to SARS-CoV-2 vaccinations is also common, its pathophysiology being unclear. People with primary headache disorders experience headache in the acute phase of COVID-19 and after vaccination more commonly than the general population. Pandemic measures, forcing lifestyle changes, seemed to have had a positive impact on migraine, and changes in headache care (telemedicine) have been effectively introduced.

CONCLUSIONS

The ongoing COVID-19 pandemic is a global challenge, having an impact on the development of secondary headaches, both in people with or without primary headaches. This has created opportunities to better understand and treat headache and to potentiate strategies to manage patients and ensure care.

Pathogenesis and progression of anosmia and dysgeusia during the COVID-19 pandemic

Severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) is the causative agent of COVID-19 which was detected in late 2019 in Wuhan, China. As of September 2022, there have been over 612 million confirmed cases of COVID-19 with over 6.5 million associated deaths. In many cases, anosmia and dysgeusia have been identified as primary symptoms of COVID-19 infection in patients. While the loss of smell (anosmia) and loss of taste (dysgeusia) due to COVID-19 infection is transient in most patients, many report that these symptoms persist following recovery. Understanding the pathogenesis of these symptoms is paramount to early treatment of the infection. We conducted a literature review of Google Scholar and PubMed to find and analyze studies discussing anosmia and dysgeusia in the context of COVID-19 to understand the progression and management of these symptoms. The mechanism for dysgeusia is largely unknown; however, pathogenesis of anosmia includes inflammation and cytokine release resulting from the infection that alters neuronal signaling, thus inducing the loss of smell that patients experience. Anosmia may be managed and potentially resolved sooner with a combination therapy of olfactory training and budesonide irrigation of the nasal cavity. It is important to note that the variants of SARS-CoV-2 are genetically distinguished from the original virion due to a mutation in their spike proteins, giving them a different symptom profile regarding anosmia and dysgeusia. This variability in symptomatology is an area of study that needs to be further explored.

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.

Cognitive Behavioral Psychotherapy after COVID-19: Opportunities and Prospects

This article reviews domestic and foreign studies on cognitive behavioral therapy techniques in treating cognitive disorders in former COVID-19 patients. Coronavirus-induced cognitive disorders include damage to the nervous system as a result of respiratory distress syndrome, cytokine storm, cerebral vascular thrombosis, direct exposure to SARS-Cov2, and inadequate immune response. Concomitant mental illnesses include autistic disorders, dementia, cognitive decline, eating disorders, suicidal behavior, anxiety, depression, post-traumatic stress, insomnia, etc. Diagnostic methods usually take into account a complex violation of mental activities, e.g., short memory span, attention deficiency, slow thinking, and various affective disorders. As a result, diagnostic methods can be divided into several areas: neuropsychological diagnostics of cognitive functions (MMSE, MOCA, FAB), identification of inadequate attitudes and behavior (WCQ, SPB, DAS), identification of violations of daily activity (The Barthel Scale), identification of psychological and psychiatric issues (Hospital Anxiety and Depression Scale, State-Trait Anxiety Inventory, Hamilton Rating Scale for Depression). Psychological care for former COVID-19 patients relies on some basic principles. Cognitive behavioral psychotherapy techniques aim at correcting cognitive distortions, teaching relaxation and self-regulation, improving problem-solving skills, and restoring cognitive functions. 

Neurological Complications of COVID-19 in the Elderly

SARS-CoV-2 virus is a β-coronavirus and produces a severe viral pneumonia which can be complicated by acute respiratory distress syndrome and multiorgan failure. As knowledge of the new coronavirus infection (COVID-19) increases, it has become known that SARS-CoV-2 has pronounced neurotropism, producing a wide spectrum of neurological complications. This article addresses the characteristics of the neurological complications of COVID-19 in elderly people.

SARS-CoV-2 Airway Infection Results in Time-dependent Sensory Abnormalities in a Hamster Model

Despite being largely confined to the airways, SARS-CoV-2 infection has been associated with sensory abnormalities that manifest in both acute and long-lasting phenotypes. To gain insight on the molecular basis of these sensory abnormalities, we used the golden hamster infection model to characterize the effects of SARS-CoV-2 versus Influenza A virus (IAV) infection on the sensory nervous system. Efforts to detect the presence of virus in the cervical/thoracic spinal cord and dorsal root ganglia (DRGs) demonstrated detectable levels of SARS-CoV-2 by quantitative PCR and RNAscope uniquely within the first 24 hours of infection. SARS-CoV-2-infected hamsters demonstrated mechanical hypersensitivity during acute infection; intriguingly, this hypersensitivity was milder, but prolonged when compared to IAV-infected hamsters. RNA sequencing (RNA-seq) of thoracic DRGs from acute infection revealed predominantly neuron-biased signaling perturbations in SARS-CoV-2-infected animals as opposed to type I interferon signaling in tissue derived from IAV-infected animals. RNA-seq of 31dpi thoracic DRGs from SARS-CoV-2-infected animals highlighted a uniquely neuropathic transcriptomic landscape, which was consistent with substantial SARS-CoV-2-specific mechanical hypersensitivity at 28dpi. Ontology analysis of 1, 4, and 30dpi RNA-seq revealed novel targets for pain management, such as ILF3. Meta-analysis of all SARS-CoV-2 RNA-seq timepoints against preclinical pain model datasets highlighted both conserved and unique pro-nociceptive gene expression changes following infection. Overall, this work elucidates novel transcriptomic signatures triggered by SARS-CoV-2 that may underlie both short- and long-term sensory abnormalities while also highlighting several therapeutic targets for alleviation of infection-induced hypersensitivity.

One Sentence Summary

SARS-CoV-2 infection results in an interferon-associated transcriptional response in sensory tissues underlying time-dependent hypersensitivity.

A Review on Headaches Due to COVID-19 Infection

Since December 2019, the time when the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was spotted, numerous review studies have been published on COVID-19 and its neuro invasion. A growing number of studies have reported headaches as a common neurological manifestation of COVID-19. Although several hypotheses have been proposed regarding the association between headache and the coronavirus, no solid evidence has been presented for the mechanism and features of headache in COVID-19. Headache also is a common complaint with the omicron variant of the virus. COVID-19 vaccination also is a cause of new-onset headaches or aggravation of the previous headache in migraine or tension headache sufferers. In this review study, the types of headaches reported in previous studies and their possible pathogenic mechanisms are outlined. To accomplish this objective, various types of headaches are classified and their patterns are discussed according to ICHD-3 diagnostic criteria, including, headaches attributed to systemic viral infection, viral meningitis or encephalitis, non-infectious inflammatory intracranial disease, hypoxia and/or hypercapnia, cranial or cervical vascular disorder, increased cerebrospinal fluid (CSF) pressure, refractive error, external-compression headache, and cough headache. Then, their pathogeneses are categorized into three main categories, direct trigeminal involvement, vascular invasion, and inflammatory mediators. Furthermore, persistent headache after recovery and the predictors of intensity is further investigated. Post-vaccination headache is also discussed in this review.

Neurological Symptoms of SARS-CoV-2 Infection in Pediatric Patients

Purpose: Coronavirus disease 2019 (COVID-19) causes various neurological symptoms in children, as well as respiratory symptoms, and the number of reported cases is increasing with the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants. This study aimed to investigate the neurological symptoms and incidence in pediatric patients hospitalized with COVID-19.Methods: We retrospectively analyzed the medical records of patients under the age of 18 diagnosed with COVID-19 and admitted to National Health Insurance Service Ilsan Hospital using real-time reverse transcription–polymerase chain reaction from December 2020 to March 2022. We reviewed data on the age of confirmed COVID-19 patients, fever, and respiratory, gastrointestinal, and neurological symptoms. We evaluated the chief complaints of hospitalization and classified them as non-neurological or neurological, according to the chief complaints that caused the most discomfort.Results: Among 376 patients, 63 (16.8%) and 313 (83.2%) patients were classified as having neurological and non-neurological symptoms, respectively. The most common neurological symptoms were headache (49, 13.0%), followed by seizures (39, 10.4%), myalgia (24, 6.4%), and dizziness (14, 3.7%). Additionally, there were patients with anosmia (nine, 2.4%), ageusia (four, 1.1%), and visual disturbance (twi, 0.5%). Of the 39 patients who experienced seizures, 15 (15/39, 51.7%) had no symptoms except fever, and seizures were the only main presenting symptom of SARS-CoV-2 infection.Conclusion: Neurological symptoms are common in pediatric COVID-19 patients. Seizures can be an early symptom of SARS-CoV-2 infection and should not be underestimated during the COVID-19 pandemic.

Neurological manifestations as prognostic factors in COVID-19: a retrospective cohort study

BACKGROUND

Neurological manifestations are frequent during COVID-19 but have been poorly studied as prognostic markers of COVID-19.

OBJECTIVES

The aim of this study was to assess whether neurological manifestations are associated with a poor prognosis of COVID-19, and which patient and COVID-19 characteristics were associated with encephalopathy.

METHODS

This was a retrospective cohort study and included patients admitted with COVID-19 in four hospitals from Recife, Brazil. Data were collected by reviewing medical records.

RESULTS

613 were included; 54.6% were male, the median age was 54 (41-68) years, 26.4% required mechanical ventilation, and 24.1% died. The neurological symptoms presented were: myalgia (25.6%), headache (22%), fatigue (22%), drowsiness (16%), anosmia (14%), disorientation (8.8%), ageusia (7.3%), seizures (2.8%), and dizziness (1.5%). Twelve patients (2%) had strokes (ischemic strokes: 9) and 149 (24.3%), encephalopathy. Older age, a prolonged hospitalization, diabetes mellitus, a previous history of stroke and having epileptic seizures during hospitalization were significantly associated with the occurrence of encephalopathy. Older age, smoking and requiring mechanical ventilation were associated with prolonged hospitalization. Older patients, those requiring mechanical ventilation and those with encephalopathy presented a significantly higher risk, while those who had anosmia presented a significantly lower risk of dying.

CONCLUSIONS

Neurological symptoms are frequent among patients with COVID-19. Encephalopathy was the most frequent neurological complication and was associated with a higher mortality. Those with anosmia had a lower mortality.

Headache associated with COVID‐19: Epidemiology, characteristics, pathophysiology, and management

Objective

Background

Method

Results

Conclusions

Heterogeneity and Risk of Bias in Studies Examining Risk Factors for Severe Illness and Death in COVID-19: A Systematic Review and Meta-Analysis

This systematic review and meta-analysis synthesized the evidence on the impacts of demographics and comorbidities on the clinical outcomes of COVID-19, as well as the sources of the heterogeneity and publication bias of the relevant studies. Two authors independently searched the literature from PubMed, Embase, Cochrane library, and CINAHL on 18 May 2021; removed duplicates; screened the titles, abstracts, and full texts by using criteria; and extracted data from the eligible articles. The variations among the studies were examined by using Cochrane, Q.; I2, and meta-regression. Out of 11,975 articles that were obtained from the databases and screened, 559 studies were abstracted, and then, where appropriate, were analyzed by meta-analysis (n = 542). COVID-19-related severe illness, admission to the ICU, and death were significantly correlated with comorbidities, male sex, and an age older than 60 or 65 years, although high heterogeneity was present in the pooled estimates. The study design, the study country, the sample size, and the year of publication contributed to this. There was publication bias among the studies that compared the odds of COVID-19-related deaths, severe illness, and admission to the ICU on the basis of the comorbidity status. While an older age and chronic diseases were shown to increase the risk of developing severe illness, admission to the ICU, and death among the COVID-19 patients in our analysis, a marked heterogeneity was present when linking the specific risks with the outcomes.

Course of disease and risk factors for hospitalization in outpatients with a SARS-CoV-2 infection

We analyzed symptoms and comorbidities as predictors of hospitalization in 710 outpatients in North-East Germany with PCR-confirmed SARS-CoV-2 infection. During the first 3 days of infection, commonly reported symptoms were fatigue (71.8%), arthralgia/myalgia (56.8%), headache (55.1%), and dry cough (51.8%). Loss of smell (anosmia), loss of taste (ageusia), dyspnea, and productive cough were reported with an onset of 4 days. Anosmia or ageusia were reported by only 18% of the participants at day one, but up to 49% between days 7 and 9. Not all participants who reported ageusia also reported anosmia. Individuals suffering from ageusia without anosmia were at highest risk of hospitalization (OR 6.8, 95% CI 2.5–18.1). They also experienced more commonly dyspnea and nausea (OR of 3.0, 2.9, respectively) suggesting pathophysiological connections between these symptoms. Other symptoms significantly associated with increased risk of hospitalization were dyspnea, vomiting, and fever. Among basic parameters and comorbidities, age > 60 years, COPD, prior stroke, diabetes, kidney and cardiac diseases were also associated with increased risk of hospitalization. In conclusion, due to the delayed onset, ageusia and anosmia may be of limited use in differential diagnosis of SARS-CoV-2. However, differentiation between ageusia and anosmia may be useful for evaluating risk for hospitalization.

Neurological manifestations in patients with COVID-19: A systematic review and meta-analysis

Introduction

The intensification of coronavirus disease 2019 (COVID‐19) complications, severe symptoms, and high mortality rate has led researchers to focus on this significant issue. While respiratory and cardiac complications have been described as high‐risk manifestations in patients with COVID‐19, neurological complications can also enhance mortality. This study aimed to evaluate the prevalence of neurological complications arises from SARS‐CoV‐2 and assess the mortality rate from neurological complications.

Material and Methods

Literature review was conducted by searching in PubMed/Medline, Web of Sciences, and Embase. After performing search strategies with relevant terms, a number of articles were excluded, including review articles, systematic review or meta‐analysis, duplicate publication of same researchers, congress abstracts, animal studies, case reports, case series, and articles reporting a history of neurological features prior to COVID‐19 infection. After retrieving the data, statistical analysis was performed using the STATA Version 14 software.

Results

From 4455 retrieved publications, 20 articles were selected for further analysis. Among 18,258 included patients, 2791 showed neurological symptoms, which were classified into different groups. Headache, confusion, and fatigue were reported as the most non‐specific neurological features in confirmed COVID‐19 patients. Psychiatric symptoms, CNS disorders, cerebrovascular disorders, CNS inflammatory disorders, PNS disorders, neuromuscular disorders, etc., were defined as specific neurological manifestations. The pooled prevalence of neurological manifestations and mortality rate of COVID‐19 patients with neurological features were estimated to be 23.0% (95% CI: 17.8–29.2) and 29.1% (95% CI: 20.3–39.8), respectively.

Conclusion

Neurological manifestations may commonly happen in patients with COVID‐19. This study reported a high prevalence of neurological complications and mortality rates in COVID‐19 patients. Therefore, patients with COVID‐19 who indicated neurological symptoms should be taken seriously and should receive early treatment to prevent undesirable events.

Characterization, treatment modalities, and self-perceived improvement of post-COVID-19 phantosmia: a case series of eleven patients

Background: Loss of smell and taste is one of the early and sensitive symptoms of COVID-19 that usually improves over time. Post-COVID-19 phantosmia, a smell distorted sensation without the presence of odorants, has deleterious and long-lasting effects on the patient's quality of life. We aimed to present our experience with phantosmia. Case presentations: We report a description of a series of eleven cases (age of 29 ± 9 years, and 54.5% females) of post-COVID-19 phantosmia without any other comorbidity, and the effects of combined treatment modalities (olfactory training, nasal irrigation with budesonide and oral prednisolone) on self-perceived improvement in phantosmia. Conclusions: We postulate that the combined 10 days oral prednisolone, smell training, and nasal irrigation for three months improved post-COVID-19 phantosmia assessed as post vs. pre self-perceived improvement, although this was not aimed at as a treatment since it was not compared to untreated controls.

Persisting olfactory dysfunction in post-COVID-19 is associated with gustatory impairment: Results from chemosensitive testing eight months after the acute infection

Olfactory and gustatory disorders are prominent symptoms of acute COVID-19. Although both senses recover in many patients within weeks to months, persistency has been described in up to 60%. However up to now most reports on the course of chemosensitive disorders after COVID-19 are not based on psychophysical testing but only on subjective patients' ratings. In this study we assessed both olfaction and gustation using psychophysical tests eight months after COVID-19. Validated psychophysical testing revealed hyposmia in 18% and hypogeusia in even 32% of 303 included patients. This shows that olfactory and especially gustatory disorders have to be seen as important chronic symptoms post-COVID-19. The high prevalence of gustatory dysfunction indicates that gustatory function does not recover or might even deteriorate in the months following the acute infection.

SARS-CoV-2 entry sites are present in all structural elements of the human glossopharyngeal and vagal nerves: Clinical implications

Background

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infections result in the temporary loss of smell and taste in about one third of confirmed cases.

Methods

We used immunohistochemistry to confirm the presence of ACE2, NRP1 and TMPRSS2 in two cranial nerves (IX and X) that mediate taste where they leave/join the medulla. Samples from three (two paraffin embedded and one frozen) postmortem samples were studied (facial (VII) nerve was not available). We also performed immunohistochemistry using the same antibodies in two human cell lines (oligodendrocytes and fibroblasts), and we isolated RNA from one nerve and performed PCR to confirm the presence of the mRNAs that encode the proteins visualized.

Findings

All three of the proteins (ACE-2, NRP1 and TMPRSS2) required for SARS-CoV-2 infections appear to be present in all cellular components (Schwann cells, axons, vascular endothelium, and connective tissue) of the human IXth and Xth nerves near the medulla. We also found their mRNAs in the nerve and in human oligodendrocytes and fibroblasts which were stained by antibodies directed at the three proteins examined.

Interpretation

Infection of the IXth and Xth nerves by the SARS-CoV-2 virus is likely to cause the loss of taste experienced by many Covid patients. Migration of the virus from the oral cavity through these nerves to brainstem respiratory centers might contribute to the problems that patients experience.

Funding

This study was supported by the Intramural Research Program of the National Institute of Dental and Craniofacial Research (NIDCR), NIH (intramural project no. ZDE000755-01), and the Human Brain Tissue Bank, Semmelweis University, Budapest, Hungary from the Hungarian Brain Research Program (2017-1.2.1-NKP-2017-00002).

Clinical, Laboratory and Imaging Characteristics of Hospitalized COVID-19 Patients with Neurologic Involvement; a Cross-Sectional Study

Introduction

Although neurologic involvement and neuroimaging abnormalities have been frequently identified in COVID-19 patients, the underlying factors remain unclear. In this study, we assessed the association of the neurological manifestations and neuroimaging features of hospitalized COVID-19 patients with their clinical, laboratory, and imaging characteristics.

Methods

This multicenter cross-sectional study was conducted between September 2020 and March 2021 at two large academic hospitals in Tehran, Iran. We used census sampling from medical records to enroll hospitalized patients with a positive COVID-19 Polymerase chain reaction (PCR) test who underwent brain imaging due to presenting any acute neurologic symptom during hospital stay.

Results

Of the 4372 hospitalized patients with COVID-19, only 211 met the inclusion criteria (35.5% with severe infection). Central nervous system and psychiatric manifestations were significantly more common in severe cases (p ≤ 0.044). Approximately, 30% had a new abnormality on their neuroimaging, with ischemic (38/63) and hemorrhagic (16/63) insults being the most common. The most frequent reasons that provoked cranial imaging were headache (27%), altered consciousness (25.6%), focal neurologic signs (19.9%), and delirium (18%). Analysis revealed a positive correlation for age, neutrophilia, lymphopenia, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) with the emergence of neuroimaging abnormalities (p ≤ 0.018). In addition, patients with new neuroimaging abnormalities had a significantly higher lung CT score than those without any pathologic findings (11.1 ± 4.8 vs. 5.9 ± 4.8, p < 0.001).

Conclusion

Approximately 30% of the study population had various acute neuroimaging findings. The lung CT score, neutrophil count, and age were strong predictors of acute neuroimaging abnormalities in hospitalized COVID-19 patients.

Neurological Prognostic Factors in Hospitalized Patients with COVID-19

We aimed to search whether neurological symptoms or signs (NSS) and the MEWS (Modified Early Warning Score) score were associated with in-hospital mortality or oxygen requirement during the first 14 days of hospitalization in COVID-19 patients recruited at the University Hospital in Krakow, Poland. The detailed clinical questionnaires on twenty NSS were either filled out by patients prospectively or retrospectively assessed by neurologists based on daily medical records. NSS were considered high or low-risk if they were associated with increased or decreased mortality in the univariable analysis. This cohort study included 349 patients with COVID-19 (median age 64, interquartile range (51-77), women 54.72%). The presence of high-risk NSS (decreased level of consciousness, delirium, seizures, and symptoms of stroke or transient ischemic attack) or its combination with the absence of low-risk NSS (headache, dizziness, decreased mood, and fatigue) increased the risk of in-hospital mortality in SARS-CoV-2 infection 3.13 and 7.67-fold, respectively. The presence of low-risk NSS decreased the risk of in-hospital mortality in COVID-19 patients more than 6-fold. Death in patients with SARS-CoV-2 infection, apart from NSS, was predicted by older age, neoplasm, and higher MEWS scores on admission. High-risk NSS or their combination with the absence of low-risk NSS increased the risk of oxygen requirement during hospitalization in COVID-19 patients 4.48 and 1.86-fold, respectively. Independent predictors of oxygen therapy during hospitalization in patients with SARS-CoV-2 infection were also older age, male sex, neoplasm, and higher MEWS score on admission.

SARS-CoV-2 entry sites are present in all structural elements of the human glossopharyngeal and vagal nerves: clinical implications

Severe acute respiratory syndrome coronavirus (SARS-CoV-2) infections result in the temporary loss of smell and taste (anosmia and dysgeusia) in about one third of confirmed cases. Several investigators have reported that the viral spike protein receptor is present in olfactory neurons. However, no study has been published to date showing the presence of viral entry sites angiotensin-converting enzyme 2 (ACE2), neuropilin1 (NRP1), and TMPRSS2, the serine protease necessary for priming the viral proteins, in human nerves that are responsible for taste sensation (cranial nerves: VII, IX and X). We used immunocytochemistry to examine three postmortem donor samples of the IXth (glossopharyngeal) and Xth (vagal) cranial nerves where they leave/join the medulla from three donors to confirm the presence of ACE2, NRP1 and TMPRSS2. Two samples were paraffin embedded; one was a frozen sample. In addition to staining sections from the latter, we isolated RNA from it, made cDNA, and performed PCR to confirm the presence of the mRNAs that encode the proteins visualized. All three of the proteins required for SARS-CoV-2 infections appear to be present in the human IXth and Xth nerves near the medulla. Direct infection of these nerves by the COVID-19 virus is likely to cause the loss of taste experienced by many patients. In addition, potential viral spread through these nerves into the adjacent brainstem respiratory centers might also aggravate the respiratory problems patients are experiencing.

Headache, anosmia, ageusia and other neurological symptoms in COVID-19: a cross-sectional study

Background

Neurological symptoms are frequent among patients with COVID-19. Little is known regarding the repercussions of neurological symptoms for patients and how these symptoms are related to one another.

Objectives

To determine whether there is an association between the neurological symptoms in patients with COVID-19, and to characterize the headache.

Method

This was a cross-sectional study. All hospital inpatients and health workers at the Hospital Universitario Oswaldo Cruz with a PCR-confirmed COVID-19 infection between March and June 2020 were considered for the study and were interviewed by telephone at least 2-months after the acute phase of the disease. These patients were identified by the hospital epidemiological surveillance department. A semi-structured questionnaire was used containing sociodemographic and clinical data and the ID-Migraine.

Results

A total of 288 patients was interviewed; 53.1% were male; with a median age of 49.9 (41.5–60.5) years; 91.7% presented some neurological symptom; 22.2% reported some neurological symptom as the symptom that troubled them most during COVID-19. Neurological symptoms were: ageusia (69.8%), headache (69.1%), anosmia (67%), myalgia (44.4%), drowsiness (37.2%), agitation (20.8%); mental confusion (14.9%), syncope (4.9%) and epileptic seizures (2.8%). Females, those who presented with fever, sore throat, anosmia/ageusia and myalgia also presented significantly more with headache (logistic regression). The most frequent headache phenotype was a non-migraine phenotype, was of severe intensity and differed from previous headaches. This persisted for more than 30 days in 18% and for more than 90 days in 10% of patients. Thirteen percent of those with anosmia and 11% with ageusia continued with these complaints after more than 90 days of the acute phase of the disease. Aged over 50 years, agitation and epileptic seizures were significantly associated with mental confusion (logistic regression).

Conclusion

Headache is frequent in COVID-19, is associated with other symptoms such as fever, sore throat, anosmia, ageusia, and myalgia, and may persist beyond the acute phase of the disease.

Supplementary Information

The online version contains supplementary material available at 10.1186/s10194-021-01367-8.

Analysis of neurology consultations in hospitalized patients with COVID-19

OBJECTIVE

The aim of this study was to evaluate patients who were hospitalized with a diagnosis of COVID-19 and were consulted by neurology during their hospital stay.

METHODS

All files of patients with COVID-19 who were admitted to Cerrahpasa Medical Faculty Hospital between March 11th and December 31st, 2020 were retrospectively reviewed, and files of patients who consulted by neurology during their stay were included. Demographic and clinical characteristics, neurologic diagnosis, outcome and related laboratory data were extracted from electronic medical records and analyzed. Patients were categorized into the first wave and second wave according to the date of hospitalization.

RESULTS

A total of 2257 patients were hospitalized for COVID-19; among them, 127 were consulted by a neurologist during their hospital stay. Fifteen patients received a consultation for possible drug interactions. Among the remaining 112 patients, the reason for neurology consultation was i. exacerbation of a neurological comorbidity vs ii. new-onset neurological manifestations. The median age was 68.5 ± 14.2 years, and 60.7% were men. Dementia and stroke were the leading neurological comorbidities. COVID-19 disease was more severe in the patients with the new-onset neurological comorbidity than in patients with exacerbation of a neurological comorbidity (p = 0.07). Serum creatinine kinase levels were higher in the new-onset patient group (p < 0.05). Exacerbation of previous neurological disease or new neurological impairment were jointly and severely related to high mortality (overall 35/112 vs 275/2145, p < 0.001; exacerbation 12/45 vs 275/2145 p < 0.01; new-onset 23/67 vs 275/2145, p < 0.001).

CONCLUSION

Serious neurological involvement is relatively uncommon in hospitalized patients with COVID-19 and is associated with increased mortality.

Use of Favipiravir for the Treatment of Coronavirus Disease 2019 in the Setting of Hospitel

OBJECTIVE

In a setting with a limited capacity for hospitalization, "hospitels" have been developed by using hotels as extension healthcare facilities for patients with mild illness. This study examined the clinical evidence of patients with coronavirus disease 2019 (COVID-19) who were treated with favipiravir, the main medication for treating COVID-19, in the hospitel setting in Thailand.

METHODS

We retrospectively collected demographic and clinical information, medication treatment, and outcome data for all patients who received favipiravir for COVID-19 during admission to a hospitel from April 27, 2021, to July 2, 2021. Risk factors for adults who could not complete treatment in a hospitel and who required hospitel transfer were analyzed.

RESULTS

In total, 421 patients were included in the study. Most patients (94.5%) received favipiravir to treat COVID-19 pneumonia. Adjunctive corticosteroids were prescribed to 42.3% of patients. Concerning the treatment outcome, 83.6% of patients completed treatment at a hospitel, and only two deaths occurred. No serious adverse drug reactions were observed. On multivariate analysis, age (odds ratio (OR) = 1.06; 95% confidence interval (CI) = 1.02-1.10, P=0.002), dyspnea (OR = 2.84; 95% CI = 1.25-6.44, P=0.013), loss of taste (OR = 107.63; 95% CI = 1.24-9337.39, P=0.040), corticosteroid use (OR = 12.56; 95% CI = 3.65-43.18, P < 0.001), and an extended duration of favipiravir use (OR = 16.91; 95% CI = 7.29-39.24, P < 0.001) were associated with a higher risk of hospitel transfer.

CONCLUSIONS

Low rates of hospitel transfer and mortality were observed in mild-to-moderate COVID-19 patients treated with favipiravir at hospitel. Caution might be required in elderly patients, patients with dyspnea or a loss of taste, and patients receiving a 10-day course of favipiravir or adjunctive corticosteroids because these patients might require further management in the hospitel.

High Frequencies of Functional Virus-Specific CD4+ T Cells in SARS-CoV-2 Subjects With Olfactory and Taste Disorders

Olfactory and taste disorders (OTD) are commonly found as presenting symptoms of SARS-CoV-2 infection in patients with clinically mild COVID-19. Virus-specific T cells are thought to play an important role in the clearance of SARS-CoV-2; therefore the study of T cell specific immune responses in patients with mild symptoms may help to understand their possible role in protection from severe disease. We evaluated SARS-CoV-2-specific T cell responses to four different peptide megapools covering all SARS-CoV-2 proteins during the acute phase of the disease in 33 individuals with mild or no other symptom beside OTD and in 22 age-matched patients with severe infection. A control group of 15 outpatients with OTD and consistently negative nasopharyngeal SARS-CoV-2 RNA swabs and virus-specific IgG serology was included in the study. Increased frequencies of virus-specific CD4⁺ and CD8⁺ T cells were found in SARS-CoV-2 positive patients with OTD compared with those with severe COVID-19 and with SARS-CoV-2 negative OTD individuals. Moreover, enhanced CD4⁺ and CD8⁺ T-cell activation induced by SARS-CoV-2 peptides was associated with higher interferon (IFN)γ production. Increased frequencies of Spike (S1/S2)-specific CD4⁺ T cells showing enhanced IFNγ secretion and granzyme B content were associated with serum spike-specific IgG in the OTD group. In conclusion, patients with SARS-CoV-2 induced OTD develop highly functional virus-specific CD4⁺ and CD8⁺ T cells during the symptomatic phase of the disease, suggesting that robust and coordinated T-cell responses provide protection against extension of COVID-19 to the lower respiratory tract.

COVID-19 neurological manifestations: correlation of cerebral MRI imaging and lung imaging—Observational study

Background

During the current pandemic, there is an increased incidence of neurologic/neuropsychiatric manifestations in patients with the novel coronavirus (COVID-19). Neurologic manifestations may be coincident or result of disease and its therapy. In the emergency department, orientation of the clinician with this issue is crucial for accurate decision making to limit the spread of infection during neurologic treatment. This study aimed to be familiar with MRI findings in patients with Neuro-COVID. Seventy patients presented with neurologic/neuropsychiatric manifestation either post COVID or during hospitalization underwent cerebral MRI from April 2020 to June 2021 (39 men and 31women; mean age 43.27, age range from 16 to 69 years).

Results

Headache (80%), is the most prevalent neurological manifestations followed by smell and taste impairment (62.9%) and stroke symptoms (45.7%). Low mood and anxiety (17.1%), prolonged fatigue (14.3%) and depression (7.1%) are the most common psychiatric symptoms. Infarctions, hematoma and demyelinating disease are the most prevalent findings. There is a week positive correlation between MRI findings and CT chest finding but without statistical significance (P-value 0.2).

Conclusions

Cerebrovascular disease and demyelinating lesions are common manifestations of COVID 19. Familiarity of neurologists and radiologist in the emergency department and in-patient with this issue is crucial to avoid misdiagnosis and the spread of infection.

Mental and neurological disorders and risk of COVID-19 susceptibility, illness severity and mortality: A systematic review, meta-analysis and call for action

BACKGROUND

Coronavirus disease 2019 (COVID-19) has evolved into a worldwide pandemic, and has been found to be closely associated with mental and neurological disorders. We aimed to comprehensively quantify the association between mental and neurological disorders, both pre-existing and subsequent, and the risk of susceptibility, severity and mortality of COVID-19.

METHODS

In this systematic review and meta-analysis, we searched PubMed, Web of Science, Embase, PsycINFO, and Cochrane library databases for studies published from the inception up to January 16, 2021 and updated at July 7, 2021. Observational studies including cohort and case-control, cross-sectional studies and case series that reported risk estimates of the association between mental or neurological disorders and COVID-19 susceptibility, illness severity and mortality were included. Two researchers independently extracted data and conducted the quality assessment. Based on I2 heterogeneity, we used a random effects model to calculate pooled odds ratios (OR) and 95% confidence intervals (95% CI). Subgroup analyses and meta-regression analysis were also performed. This study was registered on PROSPERO (registration number: CRD 42021230832).

FINDING

A total of 149 studies (227,351,954 participants, 89,235,737 COVID-19 patients) were included in this analysis, in which 27 reported morbidity (132,727,798), 56 reported illness severity (83,097,968) and 115 reported mortality (88,878,662). Overall, mental and neurological disorders were associated with a significant high risk of infection (pre-existing mental: OR 1·67, 95% CI 1·12-2·49; and pre-existing neurological: 2·05, 1·58-2·67), illness severity (mental: pre-existing, 1·40, 1·25-1·57; sequelae, 4·85, 2·53-9·32; neurological: pre-existing, 1·43, 1·09-1·88; sequelae, 2·17, 1·45-3·24), and mortality (mental: pre-existing, 1·47, 1·26-1·72; neurological: pre-existing, 2·08, 1·61-2·69; sequelae, 2·03, 1·66-2·49) from COVID-19. Subgroup analysis revealed that association with illness severity was stronger among younger COVID-19 patients, and those with subsequent mental disorders, living in low- and middle-income regions. Younger patients with mental and neurological disorders were associated with higher mortality than elders. For type-specific mental disorders, susceptibility to contracting COVID-19 was associated with pre-existing mood disorders, anxiety, and attention-deficit hyperactivity disorder (ADHD); illness severity was associated with both pre-existing and subsequent mood disorders as well as sleep disturbance; and mortality was associated with pre-existing schizophrenia. For neurological disorders, susceptibility was associated with pre-existing dementia; both severity and mortality were associated with subsequent delirium and altered mental status; besides, mortality was associated with pre-existing and subsequent dementia and multiple specific neurological diseases. Heterogeneities were substantial across studies in most analysis.

INTERPRETATION

The findings show an important role of mental and neurological disorders in the context of COVID-19 and provide clues and directions for identifying and protecting vulnerable populations in the pandemic. Early detection and intervention for neurological and mental disorders are urgently needed to control morbidity and mortality induced by the COVID-19 pandemic. However, there was substantial heterogeneity among the included studies, and the results should be interpreted with caution. More studies are needed to explore long-term mental and neurological sequela, as well as the underlying brain mechanisms for the sake of elucidating the causal pathways for these associations.

FUNDING

This study is supported by grants from the National Key Research and Development Program of China, the National Natural Science Foundation of China, Special Research Fund of PKUHSC for Prevention and Control of COVID-19, and the Fundamental Research Funds for the Central Universities.

Neuropsychiatric manifestations of COVID-19, potential neurotropic mechanisms, and therapeutic interventions

The coronavirus disease 2019 (COVID-19) pandemic has caused large-scale economic and social losses and worldwide deaths. Although most COVID-19 patients have initially complained of respiratory insufficiency, the presence of neuropsychiatric manifestations is also reported frequently, ranging from headache, hyposmia/anosmia, and neuromuscular dysfunction to stroke, seizure, encephalopathy, altered mental status, and psychiatric disorders, both in the acute phase and in the long term. These neuropsychiatric complications have emerged as a potential indicator of worsened clinical outcomes and poor prognosis, thus contributing to mortality in COVID-19 patients. Their etiology remains largely unclear and probably involves multiple neuroinvasive pathways. Here, we summarize recent animal and human studies for neurotrophic properties of severe acute respiratory syndrome coronavirus (SARS-CoV-2) and elucidate potential neuropathogenic mechanisms involved in the viral invasion of the central nervous system as a cause for brain damage and neurological impairments. We then discuss the potential therapeutic strategy for intervening and preventing neuropsychiatric complications associated with SARS-CoV-2 infection. Time-series monitoring of clinical-neurochemical-radiological progress of neuropsychiatric and neuroimmune complications need implementation in individuals exposed to SARS-CoV-2. The development of a screening, intervention, and therapeutic framework to prevent and reduce neuropsychiatric sequela is urgently needed and crucial for the short- and long-term recovery of COVID-19 patients.

COVID-19 outcomes of 10,881 patients: retrospective study of neurological symptoms and associated manifestations (Philippine CORONA Study)

Our study aimed to determine the effects of new-onset neurological symptoms (NNS) on clinically relevant outcomes in hospitalized patients with COVID-19 infection. We conducted a nationwide, comparative, retrospective, cohort study among adult, hospitalized COVID-19 patients involving 37 hospital sites from various regions in the Philippines. We included a total of 10,881 patients with confirmed COVID-19 infection (2008 had NNS while 8873 did not have NNS). The adjusted hazard ratios (aHRs) for mortality among the mild and severe cases were significantly higher by 1.660 (95% CI 1.132–2.435) and by 1.352 (95% CI 1.042–1.752), respectively, in the NNS group compared to those in the non-NNS group. The aHRs for respiratory failure in the NNS group were significantly increased by 1.914 (95% CI 1.346–2.722), by 1.614 (95% CI 1.260–2.068), and by 1.234 (95% CI 1.089–1.398) among the mild, severe, and critical cases, respectively. The aHRs for ICU admission in the NNS group were still significantly higher by 1.973 (95% CI 1.457–2.673) and by 1.831 (95% CI 1.506–2.226) among the mild and severe cases, respectively. Patients who had NNS were not significantly associated with a longer duration of ventilator dependence (adjusted odds ratio (aOR) 0.954, 95% CI 0.772–1.179), longer ICU stay (aOR 0.983, 95% CI 0.772–1.252) and longer hospital admission (aOR 1.045, 95% CI 0.947–1.153). The presence of NNS significantly increases the risk of mortality, respiratory failure and ICU admission among COVID-19 patients. Registration and associated protocol publication: ClinicalTrials.gov website (NCT04386083); Espiritu AI, Sy MCC, Anlacan VMM, Jamora RDG. The Philippine COVID-19 Outcomes: a Retrospective study Of Neurological manifestations and Associated symptoms (The Philippine CORONA study): a protocol study. BMJ Open. 2020;10:e040944.

What can the neurological manifestations of COVID-19 tell us: a meta-analysis

Background

Covid-19 became a global pandemic in 2019. Studies have shown that coronavirus can cause neurological symptoms, but clinical studies on its neurological symptoms are limited. In this meta-analysis, we aimed to summarize the various neurological manifestations that occurred in COVID-19 patients and calculate the incidence of various neurological manifestations. At the same time, we further explored the mechanism of nervous system injury and prognosis in COVID-19 patients in combination with their nervous system manifestations. This study provides a reference for early clinical identification of COVID-19 nervous system injury in the future, so as to achieve early treatment and reduce neurological sequelae.

Methods

We systematically searched all published English literature related to the neurological manifestations of COVID-19 from January 1, 2020, to April 30, 2021, in Pubmed, Embase, and Cochrane Library. The keywords used were COVID-19 and terminology related to the nervous system performance. All included studies were selected by two independent reviewers using EndNote and NoteExpress software, any disagreement was resolved by consensus or by a third reviewer, and the selected data were then collected for meta-analysis using a random-effects model.

Results

A total of 168 articles (n = 292,693) were included in the study, and the meta-analysis showed that the most common neurological manifestations of COVID-19 were myalgia(33%; 95%CI 0.30–0.37; I² = 99.17%), smell impairment(33%; 95%CI 0.28–0.38; I² = 99.40%), taste dysfunction(33%; 95%CI 0.27–0.39; I² = 99.09%), altered mental status(32%; 95%CI 0.22–0.43; I² = 99.06%), headache(29%; 95%CI 0.25–0.33; I² = 99.42%), encephalopathy(26%; 95%CI 0.16–0.38; I² = 99.31%), alteration of consciousness(13%; 95%CI 0.08–0.19; I² = 98.10%), stroke(12%; 95%CI 0.08–0.16; I² = 98.95%), dizziness(10%; 95%CI 0.08–0.13; I² = 96.45%), vision impairment(6%; 95%CI 0.03–0.09; I² = 86.82%), intracerebral haemorrhage(5%; 95%CI 0.03–0.09; I² = 95.60%), seizure(4%; 95%CI 0.02 -0.05; I² = 98.15%), encephalitis(2%; 95%CI 0.01–0.03; I² = 90.36%), Guillan-Barré Syndrome (GBS) (1%; 95%CI 0.00–0.03; I² = 89.48%).

Conclusions

Neurological symptoms are common and varied in Covid-19 infections, and a growing number of reports suggest that the prevalence of neurological symptoms may be increasing. In the future, the role of COVID-19 neurological symptoms in the progression of COVID-19 should be further studied, and its pathogenesis and assessment methods should be explored, to detect and treat early neurological complications of COVID-19 and reduce mortality.

Is loss of smell an early predictor of COVID-19 severity: a systematic review and meta-analysis

Anecdotal evidence suggests that the severity of coronavirus disease of 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is likely to be distinguished by variations in loss of smell (LOS). Thus, we conducted a meta-analysis of 45 articles that include a total of 42,120 COVID-19 patients from 17 different countries to demonstrate that severely ill or hospitalized COVID-19 patients have a lesser chance of experiencing LOS than non-severely ill or non-hospitalized COVID-19 patients (odds ratio = 0.527 [95% CI 0.373–0.744; p < 0.001] and 0.283 [95% CI 0.173–0.462; p < 0.001], respectively). We also proposed a possible mechanism underlying the association of COVID-19 severity with anosmia, which may explain why patients without sense of smell develop severe COVID-19. Variations in LOS according to the severity of COVID-19 is a global phenomenon, with few exceptions. Since severely ill patients have a lower rate of anosmia, patients without anosmia should be monitored more closely in the early stages of COVID-19, for early diagnosis of severity of illness. An understanding of how the severity of COVID-19 infection and LOS are associated has profound implications for the clinical management and mitigation strategies for the disease.

Clinical significance of olfactory dysfunction in patients of COVID-19

BACKGROUND

Currently, as the coronavirus disease (COVID-19) has become a pandemic, rapidly obtaining accurate information of patient symptoms and their progression is crucial and vital. Although the early studies in China have illustrated that the representative symptoms of COVID-19 include (dry) cough, fever, headache, fatigue, gastrointestinal discomfort, dyspnea, and muscle pain, there is increasing evidence to suggest that olfactory and taste disorder are related to the COVID-19 pandemic. Therefore, we conduct this study to review the present literature about the correlation between anosmia or dysgeusia and COVID-19.

METHODS

A comprehensive literature search in 2020 of the electronic journal databases, mainly PubMed or Web of Science, was performed using the keywords COVID-19 or severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), with hyposmia, anosmia, dysgeusia, olfactory disorder, or olfactory dysfunction. The country, study period, case number, inpatient or outpatient medical visit, evaluation method (subjective complaints of dysfunction or objective evaluation), and occurrence rate of olfactory or gustatory function were reviewed.

RESULTS

Many studies reported that the recoverable olfactory or gustatory dysfunction may play an important role as the early clinical symptom of COVID-19. It is associated with better prognosis, although further investigation and validation should be carried out.

CONCLUSION

Studies have shown that smell and taste disturbances may represent an early symptom of COVID-19 and healthcare professionals must be very vigilant when managing patients with these symptoms. In the pandemic era, this implies testing for COVID-19 by healthcare workers with full personal protective equipment.

Altered immunoemotional regulatory system in COVID-19: From the origins to opportunities

The emergence of the novel coronavirus (SARS-CoV-2) and the worldwide spread of the coronavirus disease (COVID-19) have led to social regulations that caused substantial changes in manners of daily life. The subsequent loneliness and concerns of the pandemic during social distancing, quarantine, and lockdown are psychosocial stressors that negatively affect the immune system. These effects occur through mechanisms controlled by the sympathetic nervous system (SNS) and the hypothalamic-pituitary-adrenocortical (HPA) axis that alter immune regulation, namely the conserved transcriptional response to adversity (CTRA), which promotes inflammation and diminishes antiviral responses, leading to inadequate protection against viral disease. Unhealthy eating habits, physical inactivity, sleep disturbances, and mental health consequences of COVID-19 add on to the pathological effects of loneliness, making immunity against this ferocious virus an even tougher fight. Therefore, social isolation, with its unintended consequences, has inherently paradoxical effects on immunity in relation to viral disease. Though this paradox can present a challenge, its acknowledgment can serve as an opportunity to address the associated issues and find ways to mitigate the adverse effects. In this review, we aim to explore, in detail, the pathological effects of the new social norms on immunity and present suggested methods to improve our physical, psychological, and healthcare abilities to fight viral infection in the context of the COVID-19 pandemic.