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

A multidisciplinary approach to assessment and management of long COVID cognitive concerns

Cognitive dysfunction is a commonly reported feature of Long COVID (LC). With the overlap of assessment and treatment for cognitive concerns across multiple disciplines, coupled with current guidelines supporting interdisciplinary care, the aim of this clinically focused article is to provide a review of current guidelines and research related to assessment and interventions to address LC-related cognitive concerns within clinical practice from a multidisciplinary perspective, incorporating best practices for collaboration among Clinical Neuropsychologists, Rehabilitation Psychologists, and Speech-Language Pathologists. Current guidelines for assessment and interventions for cognitive functioning are provided, with clinical suggestions for best practices offered. Additional considerations related to diversity and variable patient presentations are identified. This article provides guidance based on current research and practice standards regarding the utilization of a multidisciplinary, collaborative approach to provide comprehensive assessment and treatment for individuals with LC-related cognitive concerns.

Structural and functional brain markers of cognitive impairment in healthcare workers following mild SARS-CoV-2 infection during the original stream

Severe acute respiratory syndrome coronavirus 2 infection often involves the nervous system, leading to cognitive dysfunctions, fatigue and many other neurological signs that are becoming increasingly recognized. Despite mild forms of the disease accounting for most cases worldwide, research on the pathophysiology driving mild coronavirus disease 2019 (COVID-19) has received little attention. In this respect, recent evidence has pointed out that around 30-40% of non-critical, mild-to-moderate severity COVID-19 survivors may display cognitive disturbances several months post-illness. Hence, the impact of COVID-19 on the brain structure and function, through potential neuropathological mechanisms underpinning cognitive alterations in post-mild COVID-19 infections, remains largely unexplored. This retrospective multicentre observational cohort study, entirely based on a healthcare worker sample (n = 65; 55% females, aged 21-61), investigated the cognitive status and the structural and functional brain integrity among non-hospitalized individuals who developed mild COVID-19 symptoms during the occurrence of severe acute respiratory syndrome coronavirus 2 variants Alpha to Delta, compared with healthy controls tested before the pandemic onset. All evaluations were performed at an average of 9-month follow-up post-infection period. Participants completed a comprehensive neuropsychological assessment and structural and functional MRI exams. Radiological inspection sought to detect the presence of white matter hyperintensities on axial fluid-attenuated inversion recovery images. Global and regional grey matter integrity assessment, analysing changes in grey matter volumes and cortical thinning, and functional connectivity alterations of resting-state brain networks were also conducted. Regression analyses tested the relationships between the presence of specific cognitive impairments and potential structural and functional brain findings. Our results revealed that clinical, cognitive screening and neuropsychological examinations were average between both groups, except for specific impairments related to executive functions in the mild COVID-19. Compared to healthy controls, mild COVID-19 subjects exhibited increased juxtacortical white matter hyperintensities, thalamic and occipital volume loss and diminished resting-state functional connectivity involving the left precuneus and cuneus in default-mode network and affecting the right angular gyrus and left precuneus in the dorsal attentional network. Reduced thalamic volume was the only variable selected in the final model explaining the observed executive function impairment in mild COVID-19. The presence of cognitive, structural and functional brain abnormalities over time suggests that the action of widespread neurovascular and inflammatory phenomena on the nervous system might also occur in mild forms following COVID-19 infection rather than permanent brain damage linked to the direct or indirect action of the virus. Our findings emphasize the need to pay attention to the long-term brain-related consequences of mild COVID-19 infections during the original stream.

Neurocognitive and Neuropsychiatric Sequelae in Long COVID-19 Infection

Objective: To characterize the cognitive profile of long COVID-19 subjects and its possible association with clinical symptoms, emotional disturbance, biomarkers, and disease severity. Methods: We performed a single-center cross-sectional cohort study. Subjects between 20 and 60 years old with confirmed COVID-19 infection were included. The assessment was performed 6 months following hospital or ambulatory discharge. Excluded were those with prior neurocognitive impairment and severe neurological/neuropsychiatric disorders. Demographic and laboratory data were extracted from medical records. Results: Altogether, 108 participants were included, 64 were male (59.25%), and the mean age was 49.10 years. The patients were classified into four groups: non-hospitalized (NH, n = 10), hospitalized without Intensive Care Unit (ICU) or oxygen therapy (HOSPI, n = 21), hospitalized without ICU but with oxygen therapy (OXY, n = 56), and ICU (ICU, n = 21) patients. In total, 38 (35.18%) reported Subjective Cognitive Complaints (SCC). No differences were found considering illness severity between groups. Females had more persistent clinical symptoms and SCC than males. Persistent dyspnea and headache were associated with higher scores in anxiety and depression. Persistent fatigue, anxiety, and depression were associated with worse overall cognition. Conclusions: No cognitive impairment was found regarding the severity of post-COVID-19 infection. SCC was not associated with a worse cognitive performance, but with higher anxiety and depression. Persistent clinical symptoms were frequent independent of illness severity. Fatigue, anxiety, and depression were linked to poorer cognitive function. Tests for attention, processing speed, and executive function were the most sensitive in detecting cognitive changes in these patients.

The relationship between comprehensive geriatric assessment on the pneumonia prognosis of older adults: a cross-sectional study

BACKGROUND

The mortality of pneumonia in older adults surpasses that of other populations, especially with the prevalence of coronavirus disease 2019 (COVID-19). Under the influence of multiple factors, a series of geriatric syndromes brought on by age is one of the main reasons for the poor prognosis of pneumonia. This study attempts to analyze the impact of geriatric syndrome on the prognosis of pneumonia.

METHODS

This is a prospective cross-sectional study. Patients over 65 years old with COVID-19 and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-negative community-acquired pneumonia (SN-CAP) were included in the research. General characteristics, laboratory tests, length of stay (LOS), and comprehensive geriatric assessment (CGA) were collected. Multivariate regression analysis to determine the independent predictors of the severity, mortality, and LOS of COVID-19. At the same time, the enrolled subjects were divided into three categories by clustering analysis of 10 CGA indicators, and their clinical characteristics and prognoses were analyzed.

RESULTS

A total of 792 subjects were included in the study, including 204 subjects of SN-CAP (25.8%) and 588 subjects (74.2%) of COVID-19. There was no significant difference between non-severe COVID-19 and SN-CAP regarding mortality, LOS, and CGA (P > 0.05), while severe COVID-19 is significantly higher than both (P < 0.05). The Barthel Index used to assess the activities of daily living was an independent risk factor for the severity and mortality of COVID-19 and linearly correlated with the LOS (P < 0.05). The cluster analysis based on the CGA indicators divided the geriatric pneumonia patients into three groups: Cluster 1 (n = 276), named low ability group, with the worst CGA, laboratory tests, severity, mortality, and LOS; Cluster 3 (n = 228), called high ability group with the best above indicators; Cluster 2 (n = 288), named medium ability group, falls between the two.

CONCLUSION

The Barthel Index indicates that decreased activities of daily living are an independent risk factor for the severity, mortality, and LOS of geriatric COVID-19. Geriatric syndrome can help judge the prognosis of pneumonia in older adults.

SARS-CoV-2 infection is associated with self-reported post-acute neuropsychological symptoms within six months of follow-up

BACKGROUND

Chronic neuropsychological sequelae following SARS-CoV-2 infection, including depression, anxiety, fatigue, and general cognitive difficulties, are a major public health concern. Given the potential impact of long-term neuropsychological impairment, it is important to characterize the frequency and predictors of this post-infection phenotype.

METHODS

The Epidemiology, Immunology, and Clinical Characteristics of Emerging Infectious Diseases with Pandemic Potential (EPICC) study is a longitudinal study assessing the impact of SARS-CoV-2 infection in U.S. Military Healthcare System (MHS) beneficiaries, i.e. those eligible for care in the MHS including active duty servicemembers, dependents, and retirees. Four broad areas of neuropsychological symptoms were assessed cross-sectionally among subjects 1-6 months post-infection/enrollment, including: depression (Patient Health Questionnaire-9), anxiety (General Anxiety Disorder-7), fatigue (PROMIS® Fatigue 7a), and cognitive function (PROMIS® Cognitive Function 8a and PROMIS® Cognitive Function abilities 8a). Multivariable Poisson regression models compared participants with and without SARS-CoV-2 infection history on these measures, adjusting for sex, ethnicity, active-duty status, age, and months post-first positive or enrollment of questionnaire completion (MPFP/E); models for fatigue and cognitive function were also adjusted for depression and anxiety scores.

RESULTS

The study population included 2383 participants who completed all five instruments within six MPFP/E, of whom 687 (28.8%) had at least one positive SARS-CoV-2 test. Compared to those who had never tested positive for SARS-CoV-2, the positive group was more likely to meet instrument-based criteria for depression (15.4% vs 10.3%, p<0.001), fatigue (20.1% vs 8.0%, p<0.001), impaired cognitive function (15.7% vs 8.6%, p<0.001), and impaired cognitive function abilities (24.3% vs 16.3%, p<0.001). In multivariable models, SARS-CoV-2 positive participants, assessed at an average of 2.7 months after infection, had increased risk of moderate to severe depression (RR: 1.44, 95% CI 1.12-1.84), fatigue (RR: 2.07, 95% CI 1.62-2.65), impaired cognitive function (RR: 1.64, 95% CI 1.27-2.11), and impaired cognitive function abilities (RR: 1.41, 95% CI 1.15-1.71); MPFP/E was not significant.

CONCLUSIONS

Participants with a history of SARS-CoV-2 infection were up to twice as likely to report cognitive impairment and fatigue as the group without prior SARS-CoV-2 infection. These findings underscore the continued importance of preventing SARS-CoV-2 infection and while time since infection/enrollment was not significant through 6 months of follow-up, this highlights the need for additional research into the long-term impacts of COVID-19 to mitigate and reverse these neuropsychological outcomes.

Neurovascular coupling impairment as a mechanism for cognitive deficits in COVID-19

Components that comprise our brain parenchymal and cerebrovascular structures provide a homeostatic environment for proper neuronal function to ensure normal cognition. Cerebral insults (e.g. ischaemia, microbleeds and infection) alter cellular structures and physiologic processes within the neurovascular unit and contribute to cognitive dysfunction. COVID-19 has posed significant complications during acute and convalescent stages in multiple organ systems, including the brain. Cognitive impairment is a prevalent complication in COVID-19 patients, irrespective of severity of acute SARS-CoV-2 infection. Moreover, overwhelming evidence from in vitro, preclinical and clinical studies has reported SARS-CoV-2-induced pathologies in components of the neurovascular unit that are associated with cognitive impairment. Neurovascular unit disruption alters the neurovascular coupling response, a critical mechanism that regulates cerebromicrovascular blood flow to meet the energetic demands of locally active neurons. Normal cognitive processing is achieved through the neurovascular coupling response and involves the coordinated action of brain parenchymal cells (i.e. neurons and glia) and cerebrovascular cell types (i.e. endothelia, smooth muscle cells and pericytes). However, current work on COVID-19-induced cognitive impairment has yet to investigate disruption of neurovascular coupling as a causal factor. Hence, in this review, we aim to describe SARS-CoV-2's effects on the neurovascular unit and how they can impact neurovascular coupling and contribute to cognitive decline in acute and convalescent stages of the disease. Additionally, we explore potential therapeutic interventions to mitigate COVID-19-induced cognitive impairment. Given the great impact of cognitive impairment associated with COVID-19 on both individuals and public health, the necessity for a coordinated effort from fundamental scientific research to clinical application becomes imperative. This integrated endeavour is crucial for mitigating the cognitive deficits induced by COVID-19 and its subsequent burden in this especially vulnerable population.

Insights into attention and memory difficulties in post-COVID syndrome using standardized neuropsychological tests and experimental cognitive tasks

The COVID-19 pandemic has given rise to post-acute cognitive symptoms, often described as 'brain fog'. To comprehensively grasp the extent of these issues, we conducted a study integrating traditional neuropsychological assessments with experimental cognitive tasks targeting attention control, working memory, and long-term memory, three cognitive domains most commonly associated with 'brain fog'. We enrolled 33 post-COVID patients, all self-reporting cognitive difficulties, and a matched control group (N = 27) for cognitive and psychological assessments. Our findings revealed significant attention deficits in post-COVID patients across both neuropsychological measurements and experimental cognitive tasks, evidencing reduced performance in tasks involving interference resolution and selective and sustained attention. Mild executive function and naming impairments also emerged from the neuropsychological assessment. Notably, 61% of patients reported significant prospective memory failures in daily life, aligning with our recruitment focus. Furthermore, our patient group showed significant alterations in the psycho-affective domain, indicating a complex interplay between cognitive and psychological factors, which could point to a non-cognitive determinant of subjectively experienced cognitive changes following COVID-19. In summary, our study offers valuable insights into attention challenges faced by individuals recovering from COVID-19, stressing the importance of comprehensive cognitive and psycho-affective evaluations for supporting post-COVID individuals.

The Impact of Long COVID on Cognitive Performance and Sleep Quality: An Analysis of the Rancagua Chilean Study (RACHIS)

Background Infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can lead to prolonged symptoms post-recovery, commonly known as long-term coronavirus disease 2019 (COVID-19) or "long COVID." Neuropsychiatric consequences of long COVID include cognitive dysfunction and sleep disturbances, which significantly impair daily living. This study aimed to explore the impact of long COVID on cognitive performance and sleep quality in patients receiving outpatient care. Material and methods This study involved a random sample of 138 of 363 patients, corresponding to 38% of the cohort, who tested positive for SARS-CoV-2 via polymerase chain reaction (PCR) between May 2020 and April 2021. These unvaccinated, non-hospitalized individuals, predominantly exhibiting mild disease symptoms, were prospectively assessed 11 months post-positive PCR test. After informed consent, demographic data, memory, and concentration impairment levels were collected through interviews. Participants reporting cognitive symptoms underwent the Mini-Mental State Examination (MMSE), the Montreal Cognitive Assessment (MOCA), and the Pittsburgh Sleep Quality Index. Statistical analyses were conducted, including Student's t-test, Chi-square, Fisher's test, Kruskal-Wallis test, and Pearson correlation coefficient, with a significance threshold set at p<0.05. Results Of the 138 participants, 76 (55.1%) were female and 62 (44.9%) were male. The mean age was 45.9 years (± 13.0), with an average educational attainment of 10.4 years (± 3.7). Roughly 50% of the patients reported significant memory and concentration issues (p<0.001). Thirty-three participants underwent detailed cognitive assessments, revealing a 2:1 female-to-male ratio and a significantly higher prevalence of depression in female participants. Cognitive deficits were diagnosed in five (15.2%) participants via the MMSE and in 26 (78.8%) via the MOCA test, with notable deficits in visuospatial/executive functions, language repeat, and deferred recall (p<0.001). A lower educational level was correlated with higher cognitive deficits (p=0.03). Conclusion The study findings reveal that cognitive impairments, as a consequence of COVID-19, can persist up to 11 months post-infection. The MOCA test proved more effective in diagnosing these deficits and requires adjustments based on educational background. Sleep parameters remained largely unaffected in this cohort, likely attributed to the mild nature of the initial symptoms and the outpatient management of the disease.

Cognitive impairment after recovery from COVID-19: Frequency, profile, and relationships with clinical and laboratory indices

Cognitive impairment (CI) is regarded as a remarkable burden in COVID-19 survivors. Its prevalence and profile, and relationships with the disease clinical and laboratory indices, remain unclear. The present study investigated, in a large sample of patients recovered from COVID-19, the frequency of CI with both a face-to-face screening tool and comprehensive test battery (MCCB). The study also evaluated the profile of CI and its relationships with COVID-19 clinical and laboratory indices and with psychopathological features. Out of 1344 subjects assessed for eligibility, 736 completed the screening phase 11 months after the COVID-19 infection; 402 participated in the baseline phase and completed an in depth cognitive, clinical and laboratory assessment about one month later. More than one third of the screened subjects presented a CI (COG+); it was associated to age, education, male gender, COVID-19 severity, and presence of anosmia, dyspnea at rest and exertional dyspnea during the acute phase. COG+ subjects showed a higher severity of depression, anxiety and post-traumatic distress, and worse global functioning, than subjects without CI. The MCCB showed that 45% of the subjects had a CI involving attention, working memory, verbal learning, visual learning, and reasoning and problem solving. Finally, neurocognitive functioning was inversely correlated with LDH blood levels, a potential biomarker of disease severity. According to our findings, cognitive functioning should be routinely and periodically assessed in COVID-19 patients, especially in older subjects, who experienced more severe COVID-19 symptoms. In case of persisting dysfunctions cognitive training programs should be considered as treatment strategies.

Update on Central Nervous System Effects of the Intersection of HIV-1 and SARS-CoV-2

PURPOSE OF REVIEW

Research has shown myriad neurologic and mental health manifestations during the acute and subsequent stages of COVID-19 in people with HIV (PWH). This review summarizes the updates on central nervous system (CNS) outcomes following SARS-CoV-2 infection in PWH and highlight the existing knowledge gaps in this area.

RECENT FINDINGS

Studies leveraging electronic record systems have highlighted the excess risk of developing acute and lingering neurological complications of COVID-19 in PWH compared to people without HIV (PWoH). However, there is a notable scarcity of neuroimaging as well as blood and cerebrospinal fluid (CSF) marker studies that can confirm the potential synergy between these two infections, particularly in PWH receiving suppressive antiretroviral therapy. Considering the unclear potential interaction between SARS-CoV-2 and HIV, clinicians should remain vigilant regarding new-onset or worsening neurological symptoms in PWH following COVID-19, as they could be linked to either infection.

Preliminary Findings on Cognitive Dysfunction in University-Educated Patients After Mild COVID-19 Disease

Objective

To investigate cognitive functioning in patients with higher education having post COVID-19 condition.

Design

Prospective cohort study.

Setting

Outpatient rehabilitation clinic.

Participants

Patients (N=38; mean age, 48.5y; 71% women) at the Cognitive Post COVID-19 Clinic at Danderyd University Hospital in Stockholm, Sweden, who sought health care because of self-experienced cognitive problems. All had at least 4 years of university education and an initially mild infection (ie, most were not hospital admitted, none were admitted to intensive care).

Interventions

Not applicable.

Main Outcome Measures

Cognitive test performance assessed with a comprehensive neuropsychological test battery including Information, Matrix Reasoning, Coding, and Digit Span from Wechsler's Adult Intelligence Scale-IV, Buschke Selective Reminding Test, Rey Complex Figure Test, Ruff 2&7, Color-Word Interference Test, Verbal Fluency, and Trail Making Test. The mean time between the infection and the assessment was 18 months.

Results

Cognitive deficits were evident on tests of verbal learning and memory (Buschke Selective Reminding Test) and selective attention (Ruff 2&7). Approximately 50% of the participants had scores lower than 1 SD below the mean in the norm group on the measures of verbal learning and memory. When estimated premorbid cognitive functioning was accounted for, deficits were suggested in most cognitive domains.

Conclusions

Post COVID-19 condition seems to be associated with cognitive deficits, even in patients with high education and an initially mild infection.

Effect of oxygen therapy duration on cognitive impairment 12 months after hospitalization for SARS-COV-2 infection

OBJECTIVE

To identify predictors of persistent cognitive impairment at 12 months after hospitalization due to COVID-19 (SARS-CoV-2) infection.

DESIGN

Retrospective, single-centre study.

SUBJECTS

All consecutive patients assessed in physical and rehabilitation medicine consultations at 3 months with a neuropsychiatric testing (NPT) at 6 months.

METHODS

A Mini Mental State Examination (MMSE) was performed at 3 months and NPT at 6 and 12 months, exploring global cognitive efficiency, attention and processing speed, short-term memory and executive function. Logistic regression and receiver operating characteristic curves were used to identify predictors of persistent cognitive impairment.

RESULTS

Among 56 patients, 64.3% and 53.6% had 1 or more impaired cognitive functions at 6 and 12 months, respectively, attention and processing speed being the most represented (41.1% at 12 month). Duration of oxygen therapy (odds ratio 0.926 [0.871-0.985], p = 0.015) and MMSE score at 3 months (odds ratio 0.464 [0.276-0.783], p = 0.004) were associated with cognitive impairment at 12 months by multivariable analysis (R² 0.372-0.497).

CONCLUSIONS

Half of patients have cognitive impairment 12 months after acute SARS-CoV-2 infection requiring hospitalization. The duration of oxygen therapy in acute care could be a protective parameter. Systematic evaluation with the MMSE at 3 months after infection might be an effective tool to detect risk.

Cognitive impairments and mental health of patients with post-COVID-19: A cross-sectional study

BACKGROUND

Persistent cognitive complaints belong to the most frequent symptoms after COVID-19. This study explored the neuropsychological profile, mental health and risk factors for cognitive impairment in post-COVID-19 patients.

METHODS

The patients were recruited consecutively in the Post COVID Center of the University Hospital of Erlangen between 12/2022 and 05/2023. They underwent an extensive neuropsychological assessment including the Verbal Learning Memory Test (VLMT), the digit span backwards from the Wechsler Memory Scale-Revised (WMS-R), the Trail Making Test (TMT) Part A and B, the d2 Test of Attention and the Regensburger Verbal Fluency Test (RWT). For each cognitive domain we calculated the frequency of age-adjusted scores below the measure-specific norms. Depressive symptoms were measured with the Patient-Health-Questionnaire-9 (PHQ-9). Logistic regression analyses were computed.

RESULTS

In 110 patients (mean age: 42.5 ± 11.9 years; 68.2% women), the most frequent cognitive deficits were observed for verbal fluency, working speed, delayed recall and attention. In almost every cognitive domain high education levels were associated with a decreased risk for cognitive impairment. Higher age was a risk factor for working speed and delayed recall and a protective factor for verbal fluency. Clinically relevant depressive symptoms were associated with an elevated risk for an impairment regarding some cognitive functions.

CONCLUSION

Cognitive dysfunctions were common among the post-COVID-19 patients. Differentiated exploration of cognitive impairments is crucial for a proper characterization of the post-COVID syndrome. In future research parameters of cognitive impairment should be correlated to alterations in biological markers of the disease like markers of immunological and microcirculation change.

Repurposing the in-house generated Alzheimer's disease targeting molecules through computational and preliminary in-vitro studies for the management of SARS-coronavirus-2

Covid-19 was declared a world pandemic. Recent studies demonstrated that Covid-19 impairs CNS activity by crossing the blood-brain barrier and ensuing cognitive impairment. In this study, we have utilized Covid-19 main protease (Mpro) as a biological target to repurpose our previously reported multifunctional compounds targeting Alzheimer's disease. Molecular docking, spatial orientation, molecular dynamics simulation, MM-GBSA energy calculation, and DFT studies were carried out with these molecules. Among all the compounds, F27, F44, and F56 exhibited higher binding energy (- 8.03, - 8.65, and - 8.68 kcal/mol, respectively) over the co-crystal ligand O6K (- 7.00 kcal/mol). In MD simulation, compounds F27, F44, and F56 could make a stable complex with Mpro target throughout the simulation. The compounds were synthesized following reported methods and subjected for cytotoxicity, and assessment of their capability to cross the blood-brain barrier in PAMPA assay, and antioxidant property evaluation through DPPH assay. The compounds F27, F44, and F56 exhibited cytocompatibility with the SiHA cell line and also displayed significant antioxidant properties with IC50 = 45.80 ± 0.27 μM, 44.42 ± 0.30 μM, and 42.74 ± 0.23 μM respectively. In the PAMPA assays, the permeability coefficient (Pe) value of F27, F44, and F56 lies in the acceptable range (Pe > 4). The results of the computational and preliminary in-vitro studies strongly corroborate the potential of F27, F44, and F56 as a lead for further optimization in treating the CNS complications associated with Covid-19.

Cognitive Aspects of COVID-19

PURPOSE OF REVIEW

Since the beginning of the coronavirus disease 2019 pandemic, many lasting neurological sequelae including cognitive impairment have been recognized as part of the so-called long COVID syndrome. This narrative review summarizes the cognitive aspects of COVID-19.

RECENT FINDINGS

Studies have consistently identified attention, memory, and executive functions as the cognitive domains most often affected by COVID-19 infection. Many studies have also reported neuroimaging, biofluid, and neurophysiological abnormalities that could potentially reflect the pathophysiological aspects of post-COVID cognitive impairment. While patients suffering from dementia have an elevated risk of COVID-19 infection, increasing evidence has also indicated that COVID-19 infection may increase the risks of Alzheimer's disease, suggesting bidirectional relationships. Post-COVID cognitive dysfunction is a pervasive and multifaceted problem and we are surely in our infancy of understanding. Future elucidation into the long-term effects, mechanisms, and therapies will depend on a concerted effort from clinicians, researchers, patients, and policy-makers alike.

Cognitive impairment in long-COVID and its association with persistent dysregulation in inflammatory markers

Objective

To analyze the potential impact of sociodemographic, clinical and biological factors on the long-term cognitive outcome of patients who survived moderate and severe forms of COVID-19.

Methods

We assessed 710 adult participants (Mean age = 55 ± 14; 48.3% were female) 6 to 11 months after hospital discharge with a complete cognitive battery, as well as a psychiatric, clinical and laboratory evaluation. A large set of inferential statistical methods was used to predict potential variables associated with any long-term cognitive impairment, with a focus on a panel of 28 cytokines and other blood inflammatory and disease severity markers.

Results

Concerning the subjective assessment of cognitive performance, 36.1% reported a slightly poorer overall cognitive performance, and 14.6% reported being severely impacted, compared to their pre-COVID-19 status. Multivariate analysis found sex, age, ethnicity, education, comorbidity, frailty and physical activity associated with general cognition. A bivariate analysis found that G-CSF, IFN-alfa2, IL13, IL15, IL1.RA, EL1.alfa, IL45, IL5, IL6, IL7, TNF-Beta, VEGF, Follow-up C-Reactive Protein, and Follow-up D-Dimer were significantly (p<.05) associated with general cognition. However, a LASSO regression that included all follow-up variables, inflammatory markers and cytokines did not support these findings.

Conclusion

Though we identified several sociodemographic characteristics that might protect against cognitive impairment following SARS-CoV-2 infection, our data do not support a prominent role for clinical status (both during acute and long-stage of COVID-19) or inflammatory background (also during acute and long-stage of COVID-19) to explain the cognitive deficits that can follow COVID-19 infection.

Cellular and Molecular Mechanisms of Pathogenic and Protective Immune Responses to SARS-CoV-2 and Implications of COVID-19 Vaccines

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has devastated the world with coronavirus disease 2019 (COVID-19), which has imparted a toll of at least 631 million reported cases with 6.57 million reported deaths. In order to handle this pandemic, vaccines against SARS-CoV-2 have been developed and billions of doses of various vaccines have been administered. In the meantime, several antiviral drugs and other treatment modalities have been developed to treat COVID-19 patients. At the end of the day, it seems that anti-SARS-CoV-2 vaccines and newly developed antiviral drugs may be improved based on various new developments. COVID-19 represents a virus-induced, immune-mediated pathological process. The severity of the disease is related to the nature and properties of the host immune responses. In addition, host immunity plays a dominant role in regulating the extent of COVID-19. The present reality regarding the role of anti-SARS-CoV-2 vaccines, persistence of SARS-CoV-2 infection even three years after the initiation of the pandemic, and divergent faces of COVID-19 have initiated several queries among huge populations, policy makers, general physicians, and scientific communities. The present review aims to provide some information regarding the molecular and cellular mechanisms underlying SARS-CoV-2 infection.

Attention and memory after COVID-19 as measured by neuropsychological tests: Systematic review and meta-analysis

COVID-19 is associated with a range of sequelae, including cognitive dysfunctions as long-standing symptoms. Considering that the number of people infected worldwide keeps growing, it is important to understand specific domains of impairments to further organize appropriate rehabilitation procedures. In this study we conducted a meta-analysis to investigate specific cognitive functions impacted by COVID-19. A literature search was conducted in Web of Science, Scopus, PubMed, Academic Search Premier, Health Source: Nursing/Academic Edition, and preprint databases (OSF and PsyArXiv via OSF Preprints, medRxiv, bioRxiv, Research Square). We included the studies that compared cognitive functioning in COVID-19 reconvalescents and healthy controls, and used at least one validated neuropsychological test. Our findings show that short-term memory in the verbal domain, and possibly, visual short-term memory and attention, are at risk in COVID-19 reconvalescents. The impact of COVID-19 on cognitive functioning has yet to be studied in detail. In the future more controlled studies with validated computerized tests might help deepen our understanding of the issue. PSYCINFO CLASSIFICATION: 3360 Health Psychology & Medicine.

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.

Cognitive Impairment after Post-Acute COVID-19 Infection: A Systematic Review of the Literature

The present study aims to provide a critical overview of the literature on the relationships between post-acute COVID-19 infection and cognitive impairment, highlighting the limitations and confounding factors. A systematic search of articles published from 1 January 2020 to 1 July 2022 was performed in PubMed/Medline. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Only studies using validated instruments for the assessment of cognitive impairment were included. Out of 5515 screened records, 72 studies met the inclusion criteria. The available evidence revealed the presence of impairment in executive functions, speed of processing, attention and memory in subjects recovered from COVID-19. However, several limitations of the literature reviewed should be highlighted: most studies were performed on small samples, not stratified by severity of disease and age, used as a cross-sectional or a short-term longitudinal design and provided a limited assessment of the different cognitive domains. Few studies investigated the neurobiological correlates of cognitive deficits in individuals recovered from COVID-19. Further studies with an adequate methodological design are needed for an in-depth characterization of cognitive impairment in individuals recovered from COVID-19.

Cognitive impairments in patients with subacute coronavirus disease: Initial experiences in a post-coronavirus disease clinic

Background

A significant number of patients experience persistent cognitive impairment after coronavirus disease (COVID-19). This study aimed to investigate the cognitive function of patients in the subacute phase of COVID-19 and to identify the clinical factors associated with cognitive sequelae.

Materials and methods

Data from patients who visited the psychiatric department of our post-COVID clinic between March and May 2022 were analyzed. The results of neuropsychiatric function tests, including the digit span forward (attention/processing speed) and backward (working memory) tests, the trail making test part A (attention/processing speed) and part B (executive functioning), and the Stroop word color interference test (executive functioning), as well as clinical data from 40 patients in the subacute phase of COVID-19 were analyzed. We calculated the frequency of impairments in each cognitive measure, defined as a z-score of ≤−1.5 standard deviations below measure-specific age- and sex-adjusted norms.

Results

Of the participants, 72.5% (n = 29) had impairments in at least one cognitive domain. Impairment in executive function was the most frequent (64.9%), followed by impairments in processing speed/attention (52.5%) and working memory (42.5%). Age was inversely correlated with T scores in all cognitive function tests.

Conclusion

Regular examination of cognitive function is needed, especially in elderly individuals, regardless of the subjective symptom manifestations.

The association between objective cognitive measures and ecological-functional outcomes in COVID-19

Background

Cognitive dysfunctions, both subjective and detectable at psychometric testing, may follow SARS-CoV-2 infection. However, the ecological-functional relevance of such objective deficits is currently under-investigated. This study thus aimed at investigating the association between objective cognitive measures and both physical and cognitive, ecological-functional outcomes in post-COVID-19.

Methods

Forty-two COVID-19-recovered individuals were administered the Mini-Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA). The Functional Independence Measure (FIM) was adopted to assess functional-ecological, motor/physical (FIM-Motor) and cognitive (FIM-Cognitive) outcomes at admission (T0) and discharge (T1).

Results

When predicting both T0/T1 FIM-total and-Motor scores based on MMSE/MoCA scores, premorbid risk for cognitive decline (RCD) and disease-related features, no model yielded a significant fit. However, the MoCA - but not the MMSE significantly predicted T0/T1 FIM-Cognitive scores. The MoCA was significantly related only to T0/T1 FIM-Cognitive Memory items.

Discussion

Cognitive measures are not associated with physical/motor everyday-life outcomes in post-COVID-19 patients. The MoCA may provide an ecological estimate of cognitive functioning in this population.