Neurocognitive deficits in severe COVID-19 infection: Case series and proposed model

Neurological, psychological, psychosocial complications of long-COVID and their management

Since it first appeared, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has had a significant and lasting negative impact on the health and economies of millions of individuals all over the globe. At the level of individual health too, many patients are not recovering fully and experiencing a long-term condition now commonly termed 'long-COVID'. Long-COVID is a collection of symptoms which must last more than 12 weeks following initial COVID infection, and which cannot be adequately explained by alternate diagnoses. The neurological and psychosocial impact of long-COVID is itself now a global health crisis and therefore preventing, diagnosing, and managing these patients is of paramount importance. This review focuses primarily on: neurological functioning deficits; mental health impacts; long-term mood problems; and associated psychosocial issues, among patients suffering from long-COVID with an eye towards the neurological basis of these symptoms. A concise account of the clinical relevance of the neurological and psychosocial impacts of long-COVID, the effects on long-term morbidity, and varied approaches in managing patients with significant chronic neurological symptoms and conditions was extracted from the literature, analysed and reported. A comprehensive account of plausible pathophysiological mechanisms involved in the development of long-COVID, its management, and future research needs have been discussed.

[Formula: see text] Cognitive disengagement syndrome in pediatric patients with long COVID: associations with mood, anxiety, and functional impairment

Children with long COVID often report symptoms that overlap with cognitive disengagement syndrome (CDS, previously sluggish cognitive tempo (SCT)), a set of behaviors distinct from attention-deficit/hyperactivity disorder (ADHD) including excessive daydreaming, mental fogginess, and slowed behavior and thinking. Those with long COVID also frequently report low mood and anxiety, which are linked to CDS. The relationships between cognitive difficulties, mood, and functional impairment have yet to be explored in pediatric long COVID. Specifically, it is unclear how much cognitive difficulties (CDS, inattention) contribute to functional impairment, when accounting for mood/anxiety symptoms in this population. Retrospective parent-reported data was collected from 34 patients with long COVID (22 females, Mage = 14.06 years, SD = 2.85, range 7-19) referred for neuropsychological consultation through a multidisciplinary Post-COVID-19 clinic. Compared to community and clinically referred samples, on average, long COVID patients showed elevated CDS symptoms, including Sluggish/sleepy (e.g., fatigue) and Low Initiation subscales (e.g., difficulty performing goal directed behaviors). Low Initiation, mood, anxiety, and inattention were associated with functional impairment. In multiple hierarchical regression models, after controlling for mood and anxiety, Low Initiation and inattention were no longer predictive of functional impairment. Instead, anxiety remained the sole predictor of functional impairment. Our results demonstrate that children with long COVID have high levels of CDS symptoms. The association between cognitive difficulties and functional impairment dissipated with the inclusion of mood and anxiety, suggesting behavioral health interventions targeting anxiety may help improve daily functioning and quality of life in pediatric long COVID patients.

Comparison of lifestyle, cognitive function, mental health, and quality of life between hospitalized older adults with COVID-19 and non-COVID-19 in South Korea: a cross-sectional study

BACKGROUND

The coronavirus disease (COVID-19) pandemic has greatly impacted older adults, resulting in many deaths. The impact of lifestyle and mental health on vulnerable groups, such as older adults, can be large and long lasting. Therefore, this study aimed to investigate the effects of COVID-19 confirmation on cognition, lifestyle, mental health, and quality of life in adults aged 55 years.

METHODS

The sample consisted of 111 people in the COVID group and 189 people in the non-COVID group aged over 55 years in South Korea. An online survey was conducted between January and May 2022. Participants responded to the following assessment tools: Yonsei Lifestyle Profile, Prospective and Retrospective Memory (PRMQ), Subjective Memory Complaints Questionnaire (SMCQ), Visual Analogue Scale, Patient Health Questionnaire-9 (PHQ-9), Insomnia Severity Index (ISI), Fear of COVID-19 Scale (FCV-19 S), and the World Health Organization Quality of Life Scale abbreviated version (WHOQOL-BREF). Differences in lifestyle, cognition, depression, anxiety, and quality of life were compared between the two groups.

RESULTS

There were significant differences in physical activity, diet, the total score of the PRMQ, PM (a sub-score of the PRMQ), PHQ-9, Korean version of the ISI (ISI-K), and WHOQOL-BREF scores between the COVID and non-COVID groups. However, there were no significant differences in activity participation, Self-Rating Anxiety Scale (SAS), or FCV-19 S between groups.

CONCLUSIONS

The study confirms that COVID-19 negatively affects memory, physical activity, diet, quality of life, depression, and insomnia in the older adults. Therefore, this study implicated that prevention and intervention strategies required improving the memory, lifestyle, and mental health of older adults with COVID-19.

TRIAL REGISTRATION

The study was conducted in accordance with the Declaration of Helsinki, and approved by the Institutional Review Board of Yonsei university in Korea (Registration number: 1041849-202112-SB-226-03, Date of registration: 01042022).

Cognitive impairment and neuropsychiatric symptoms among individuals with history of symptomatic SARS-CoV-2 infection: a retrospective longitudinal study

COVID-19 is a multisystem disease caused by the RNA virus (coronavirus 2 or SARS-CoV-2) that can impact cognitive measures.

Objective

To identify the main cognitive and neuropsychiatric symptoms in adults who had no cognitive complaints prior to the infection. Specifically, to observe the trajectory of cognitive and neuropsychiatric performance after 6 months.

Methods

This is a retrospective longitudinal study. Forty-nine patients (29 reassessed after 6 months), with a positive PCR test, with no prior cognitive complaints that only presented after the infection and without a history of structural, neurodegenerative or psychiatric neurological diseases. A brief cognitive assessment battery (MoCA), the Trail Making Test (TMT-A, B, ∆), and the Verbal Fluency Test were used, as well as the scales (Hospital Anxiety and Depression Scale-HADS, Fatigue Severity Scale-FSS). Correlation tests and group comparison were used for descriptive and inferential statistics. Level of significance of α=5%.

Results

Mean age of 50.4 (11.3), 12.7 (2.8) years of education, higher percentage of women (69.8%). No psycho-emotional improvement (depression and anxiety) was observed between the evaluations, and patients maintained the subjective complaint of cognitive changes. The HAD-Anxiety scale showed a significant correlation with TMT-B errors. The subgroup participating in cognitive stimulation and psychoeducation showed improvement in the global cognition measure and the executive attention test.

Conclusion

Our results corroborate other studies that found that cognitive dysfunctions in post-COVID-19 patients can persist for months after disease remission, as well as psycho-emotional symptoms, even in individuals with mild infection. Future studies, with an increase in casuistry and control samples, are necessary for greater evidence of these results.

Memory, Emotion, and Quality of Life in Patients with Long COVID-19

(1) Background: Persistent COVID is characterized by the presence of fatigue, mental fog, and sleep problems, among others. We aimed to study cognitive abilities (attention, executive functions, memory, language) and psychological and emotional factors in a group of participants of the population with persistent COVID-19 and asymptomatic or non-COVID-19-infected patients; (2) Methods: A total of 86 participants aged 18 to 66 years (X = 46.76) took part in the study, with 57 individuals (66.27%) in the experimental group and 29 (33.73%) in the control group. A comprehensive assessment included neuropsychological evaluations, evaluations of anxious and depressive symptomatology, assessments of the impact of fatigue, sleep quality, memory failures in daily life, and the perceived general health status of the participants; (3) Results: significant differences between groups were found in incidental learning within the Key Numbers task (U = 462.5; p = 0.001; p = 0.022) and in the Direct Digit Span (U = 562; p = 0.022), but not in the Inverse Digit Span (U = 632.5; p = 0.105). Differences were also observed in the prospective memory task of the Rivermead Prospective Memory Tasks (from the Rivermead Behavioural Memory Test) in the recall of quotations (U = 610; p = 0.020) as well as in the recall of objects (U = 681.5; p = 0.032). Concerning the task of verbal fluency, significant differences were found for both phonological cues (p- and s-) (t = -2.190; p = 0.031) and semantic cues (animals) (t = -2.277; p = 0.025). In terms of the psychological impact assessment, significant differences were found in the emotional impact across all variables studied (fatigue, quality of sleep, memory lapses, and the perceived general health status), except for quality of life; (4) Conclusions: Our results suggest that the sequelae derived from persistent COVID may have an impact on people's lives, with higher levels of anxiety and depression, worse sleep quality, a greater number of subjective memory complaints, and a greater feeling of fatigue and impact on quality of life. Furthermore, poorer performance was observed in memory and verbal fluency.

Neurocognitive deficits in COVID-19 patients five months after discharge from hospital

This observational cohort study explored objective neurocognitive deficits in COVID-19 patients five months after discharge, and any associations with demographic factors and disease severity indicators. Medical notes of all COVID-19 patients admitted to hospital in Region Östergötland, Sweden, March-May 2020, were reviewed. After applying exclusion criteria, 433 patients were screened by telephone. Of these, 185 patients reported persistent and concerning post-COVID-19 problems, including but not restricted to cognitive functions, and were invited to a clinical evaluation. The Repeatable Battery for Assessment of Neuropsychological Status (RBANS) and Colour-Word Interference Test (CWIT) were used to assess immediate memory, visuo-spatial function, language, attention, delayed memory, and executive function. A total of 133 patients had valid test performances. Mean RBANS Global Cognition Score was 83.4, with 37% scoring below cut-off (1.5 SD). Deficits in Attention and Memory indices were most common, each affecting approximately 30% of the patients. After adjustment for sex, language, level of education and premorbid function, neurocognitive performance was positively associated with length of hospital stay, but not with the disease severity indicators WHO CPS and CRP. Findings support that comprehensive neuropsychological assessment should be performed when patients report post-COVID-19 symptoms that affect daily life.

Neuropsychological Profile of Hospitalized Patients Due to COVID-19: Clinical and Inflammatory Correlates

OBJECTIVES

In the present study, we investigated the pattern of cognitive difficulties in hospitalized patients due to COVID-19 and its relation with the clinical features of the disease.

METHOD

Forty hospitalized patients with COVID-19 [mean age: 46.98 years (SD = 9.30); mean years of education: 13.65 (SD = 2.07) and 40 sex-, age- and education-matched healthy controls completed a set of neuropsychological measures administered by telephone. Participants' premorbid intellectual skills and patients' anxiety and depressive symptoms were also evaluated. The association of COVID-19-related biomarkers [oxygen saturation (SpO2), C-reactive protein (CRP), D-dimer and ferritin levels] with neuropsychological performances was examined with a series of hierarchical multiple linear regression analyses, after controlling for demographic and clinical characteristics, psychological distress and premorbid intellectual skills.

RESULTS

Patients performed worse than healthy participants on measures of verbal memory, attention and working memory. SpO2 levels were associated with patients' performance on verbal and working memory, whereas CRP levels were associated with performance on verbal memory, abstract reasoning and verbal fluency, after controlling for demographic and clinical characteristics. Ferritin levels predicted performance on the verbal fluency test, whereas D-dimer levels did not predict any of the neuropsychological measures.

CONCLUSIONS

Cognitive difficulties in verbal memory, attention and working memory were noted in patients with COVID-19. Markers of hyperinflammation predicted patients' performance above and beyond demographic characteristics, duration of symptoms, length of hospitalization and psychological distress.

Long-term cognitive dysfunction after the COVID-19 pandemic: a narrative review

Introduction

SARS-CoV-2, the virus responsible for the COVID-19 pandemic, has brought a conglomerate of novel chronic disabling conditions described as 'Long COVID/Post-COVID-19 Syndrome'. Recent evidence suggests that the multifaceted nature of this syndrome results in both pulmonary and extrapulmonary sequelae,chronic dyspnoea, persistent fatigue, and cognitive dysfunction being the most common, debilitating symptoms. Several mechanisms engender or exacerbate cognitive impairment, including central nervous system and extra-central nervous system causes, although the exact mechanism remains unclear. Both hospitalized and non-hospitalized patients may suffer varying degrees of cognitive impairment, ranging from fatigue and brain fog to prolonged deficits in memory and attention, detrimental to the quality-of-life years post-recovery. The aim of this review is to understand the underlying mechanisms, associations, and attempts for prevention with early intervention of long-term cognitive impairment post-COVID-19.

Methodology

A systematic search was conducted through multiple databases such as Medline, National Library of Medicine, Ovid, Scopus database to retrieve all the articles on the long-term sequalae of cognitive dysfunction after SARS-CoV-2 infection. The inclusion criteria included all articles pertinent to this specific topic and exclusion criteria subtracted studies pertaining to other aetiologies of cognitive dysfunction. This search was carefully screened for duplicates and the relevant information was extracted and analysed.

Results/discussion

To date, the exact pathogenesis, and underlying mechanisms behind cognitive dysfunction in COVID-19, remain unclear, hindering the development of adequate management strategies. However, the proposed mechanisms suggested by various studies include direct damage to the blood-brain barrier, systemic inflammation, prolonged hypoxia, and extended intensive care admissions. However, no clear-cut guidelines for management are apparent.

Conclusion

This review of the COVID-19 pandemic has elucidated a new global challenge which is affecting individuals' quality of life by inducing long-term impaired cognitive function. The authors have found that comprehensive evaluations and interventions are crucial to address the cognitive sequelae in all COVID-19 patients, especially in patients with pre-existing cognitive impairment. Nevertheless, the authors recommend further research for the development of relevant, timely neurocognitive assessments and treatment plans.

Neuropsychological deficits in patients with persistent COVID-19 symptoms: a systematic review and meta-analysis

Long-term persistent symptoms of COVID-19 affect 30-80% of patients who have recovered from the disease and may continue for a long time after the disease has been overcome. The duration of these symptoms over time might have consequences that affect different aspects of health, such as cognitive abilities. The main objective of this systematic review and meta-analysis was to objectify the persistent COVID-19 cognitive deficits after acute phase of infection and to summarize the existing evidence. Additionally, we aimed to provide a comprehensive overview to further understand and address the consequences of this disease. Our protocol was registered in PROSPERO (CRD42021260286). Systematic research was conducted in the Web of Science, MEDLINE, PubMed, PsycINFO, Scopus, and Google Scholar databases from January 2020 to September 2021. Twenty-five studies were included, six of which were analyzed for the meta-analysis, and consisted of 175 patients who had recovered from COVID-19 and 275 healthy individuals. Analyses of cognitive performance of post-COVID-19 patients and healthy volunteers were compared using a random-effects model. The results showed an overall medium-high effect size (g = -.68, p = .02) with a 95% CI (-1.05 to -.31), with a significantly moderate level of heterogeneity among studies (Z = 3.58, p < .001; I2 = 63%). The results showed that individuals who had recovered from COVID-19 showed significant cognitive deficits compared to controls. Future studies should carefully assess the long-term progression of cognitive impairments in patients with persistent COVID-19 symptoms, as well as the effectiveness of rehabilitation interventions. Nevertheless, there is an urgent need to know the profile to speed up development of prevention plans as well as specific interventions. Since more information is being obtained and more studies are being conducted on the subject, the need to examine this symptomatology multidisciplinary to achieve greater scientific evidence of its incidence and prevalence has become increasingly clear.

Mentation Tracks Severity but not Oxygenation in Obstructive Sleep Apnea

There is a rough consensus, after decades of research, that obstructive sleep apnea (OSA) is associated with mild cognitive impairments, especially in areas of executive functioning (EF), attention/working memory (A/WM), episodic memory (EM), and speed of speed of information processing (SIP). However, there is less consensus as to whether apnea severity matters for these impairments, which sleep variables matter most to which cognitive domains, whether common OSA comorbidities contribute to these determinations, or whether the apparent associations are really artifacts of these comorbidities. In this study, 40 participants with OSA submitted to polysomnography and to neuropsychological assessment with an expanded Halstead-Reitan Test Battery. Aggregates of tests to cover the four cognitive domains mentioned above were linearly regressed on the apnea-hypopnea index (AHI), the nadir of oxygen saturation (NOS), and hypertension and diabetes mellitus (scored present or absent). The AHI predicted both EF (p = .015; sr2 = .13) and A/WM (p = .023; sr2 = 11) in the primary analyses, and EM (p = .027; sr2 = .10) in the secondary analyses. Thus, AHI may affect EF, A/WM and perhaps EM beyond NOS and beyond two of OSA's most common comorbidities. Implications of these findings are discussed here.

Persistent olfactory learning deficits during and post-COVID-19 infection

Quantifying olfactory impairments can facilitate early detection of Coronavirus disease 2019 (COVID-19). Despite being a debated topic, many reports provide evidence for the neurotropism of SARS-CoV-2. However, a sensitive, specific, and accurate non-invasive method for quantifying persistent neurological impairments is missing to date. To quantify olfactory detectabilities and neurocognitive impairments in symptomatic COVID-19 patients during and post-infection periods, we used a custom-built olfactory-action meter (OAM) providing accurate behavioral readouts. Ten monomolecular odors were used for quantifying olfactory detectabilities and two pairs of odors were employed for olfactory matching tests. We followed cohorts of healthy subjects, symptomatic patients, and recovered subjects for probing olfactory learning deficits, before the Coronavirus Omicron variant was reported in India. Our method identifies severe and persistent olfactory dysfunctions in symptomatic patients during COVID-19 infection. Symptomatic patients and recovered subjects showed significant olfactory learning deficits during and post-infection periods, 4-18 months, in comparison to healthy subjects. On comparing olfactory fitness, we found differential odor detectabilities and olfactory function scores in symptomatic patients and asymptomatic carriers. Our results indicate probable long-term neurocognitive deficits in COVID-19 patients imploring the necessity of long-term tracking during post-infection period. Differential olfactory fitness observed in symptomatic patients and asymptomatic carriers demand probing mechanisms of potentially distinct infection routes.

Brain functional connectivity alterations associated with neuropsychological performance 6-9 months following SARS-CoV-2 infection

Neuropsychological deficits and brain damage following SARS-CoV-2 infection are not well understood. Then, 116 patients, with either severe, moderate, or mild disease in the acute phase underwent neuropsychological and olfactory tests, as well as completed psychiatric and respiratory questionnaires at 223 ± 42 days postinfection. Additionally, a subgroup of 50 patients underwent functional magnetic resonance imaging. Patients in the severe group displayed poorer verbal episodic memory performances, and moderate patients had reduced mental flexibility. Neuroimaging revealed patterns of hypofunctional and hyperfunctional connectivities in severe patients, while only hyperconnectivity patterns were observed for moderate. The default mode, somatosensory, dorsal attention, subcortical, and cerebellar networks were implicated. Partial least squares correlations analysis confirmed specific association between memory, executive functions performances and brain functional connectivity. The severity of the infection in the acute phase is a predictor of neuropsychological performance 6-9 months following SARS-CoV-2 infection. SARS-CoV-2 infection causes long-term memory and executive dysfunctions, related to large-scale functional brain connectivity alterations.

Cognitive Deficits in the Acute Phase of COVID-19: A Review and Meta-Analysis

This meta-analysis was conducted to quantify the risk of patients exhibiting cognitive deficits in the acute phase of COVID-19 at the time of the first variants (i.e., before the vaccine) and quantify the potential vulnerability of older patients and those who experienced more severe respiratory symptoms. To this end, we searched the LitCovid and EMBASE platforms for articles, including preprints, and included all studies (n = 48) that featured a measurement of cognition, which encompassed 2233 cases of COVID-19. Of these, 28 studies reported scores on global cognitive efficiency scales administered in the acute phase of COVID-19 (up to 3 months after infection). We were able to perform a meta-analysis of proportions on 24 articles (N_patients = 943), and a logistic regression on 18 articles (N_patients = 518). The meta-analysis for proportion indicated that 52.31% of patients with COVID-19 exhibited cognitive deficits in the acute phase. This high percentage, however, has to be interpreted taking in consideration the fact that the majority of patients were hospitalized, and some presented neurological complications, such as encephalopathy. A bootstrap procedure with random resampling revealed that an age of 59 was the threshold at which one would be more prone to present cognitive deficits. However, the severity of respiratory symptoms did not influence the scores on a global cognitive efficiency scale. Overall, our results indicated that neuropsychological deficits were a major consequence of the acute phase of the first forms of COVID-19.

[Speech intelligibility in adults after the new coronavirus infection (COVID-19)]

OBJECTIVE

The research was aimed to assess speech intelligibility in adults after the new coronavirus infection (COVID-19), state of peripheral and central parts of auditory system and cognitive functions.

MATERIAL AND METHODS

26 people complaining about hearing loss, poor speech intelligibility and/or tinnitus after COVID-19 were examined. All the patients underwent the basic audiological assessment before COVID-19. Extended testing in patients after COVID-19 included: pure tone audiometry, impedancemetry, speech audiometry in quiet and noise (evaluation of monosyllabic words intelligibility and the Russian matrix sentence test RuMatrix), the alternating binaural speech test, the dichotic digits test and the Montreal Cognitive Assessment (MoCA).

RESULTS

The most significant deviations from the normative values were obtained in the RuMatrix test and the dichotic digits test that may be due to both central auditory processing disorder and memory impairment. Low MoCA scores were obtained in 62% of patients.

CONCLUSION

Deterioration of speech intelligibility after COVID-19 was revealed, both in patients with hearing loss and with normal hearing that corresponded to their complaints. It may be caused by central auditory disorder, memory impairment or cognitive status lesion. The correlation found between the results of the RuMatrix test in noise and the severity of the COVID-19 may indicate the impact of the virus on the auditory cortex.

Preliminary Validity of a Telephone-Based Neuropsychological Battery in a Consecutive Series of Persons with HIV Disease Referred for Clinical Evaluation

OBJECTIVE

The COVID-19 pandemic necessitated use of remote assessments by clinical neuropsychologists. Telehealth was particularly important for vulnerable groups, including persons living with HIV (PLWH); however, limited internet access can be a serious barrier to care. This study examined the preliminary validity of a telephone-based neuropsychological assessment in a clinical sample of PLWH.

METHOD

A consecutive series of 59 PLWH were assessed via telephone at an HIV clinic in the southern U.S. between April 2020 and July 2022. The battery included auditory-verbal neuropsychological tests of memory, attention, and executive functions, and questionnaires assessing self-reported mood and activities of daily living (ADL).

RESULTS

Study measures demonstrated acceptable internal consistency. PLWH demonstrated worse neuropsychological performance compared with expectations derived from the normal curve and an HIV-seronegative adult sample (N = 44). PLWH assessed via telephone demonstrated similar impairment rates to that of a consecutive series of PLWH (N = 41) assessed in-person immediately prior to the pandemic. Higher telephone-based global neuropsychological scores were related to younger age, more education, better fund of knowledge, White race/ethnicity, fewer medical conditions, and fewer depression symptoms. Global neuropsychological impairment was strongly and independently associated with greater dependence in ADL domains, particularly for instrumental activities.

CONCLUSIONS

Although telephone-based approaches to neuropsychological assessment are not ideal, these data provide support for the feasibility, internal consistency, and preliminary validity of this method in a consecutive clinical series of PLWH. The direct comparability of telephone-based and in-person neuropsychological assessments remains to be determined by prospective, counterbalanced study designs examining both PLWH and seronegative individuals.

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.

Psychiatric and neurological complications of long COVID

COVID-19 was primarily considered a pulmonary disease with extrapulmonary manifestations. As the pandemic spread, there has been growing evidence that the disease affects various organs/systems, including the central and peripheral nervous systems. Accumulation of clinical data demonstrates that in a large population of survivors impairments in the function of one or more organs may persist for a long time, a phenomenon commonly known as post COVID or long COVID. Fatigue and cognitive dysfunction, such as concentration problems, short-term memory deficits, general memory loss, a specific decline in attention, language and praxis abilities, encoding and verbal fluency, impairment of executive functions, and psychomotor coordination, are amongst the most common and debilitating features of neuropsychatric symptoms of post COVID syndrome. Several patients also suffer from compromised sleep, depression, anxiety and post-traumatic stress disorder. Patients with long COVID may demonstrate brain hypometabolism, hypoperfusion of the cerebral cortex and changes in the brain structure and functional connectivity. Children and adolescents represent a minority of COVID-19 cases, so not surprisingly data on the long-term sequelae after SARS-CoV-2 infections in these age groups are scarce. Although the pathogenesis, clinical characteristics, epidemiology, and risk factors of the acute phase of COVID-19 have been largely explained, these areas are yet to be explored in long COVID. This review aims to provide an update on what is currently known about long COVID effects on mental health.

Disentangling the cognitive, physical, and mental health sequelae of COVID-19

As COVID-19 cases exceed hundreds of millions globally, many survivors face cognitive challenges and prolonged symptoms. However, important questions about the cognitive effects of COVID-19 remain unresolved. In this cross-sectional online study, 478 adult volunteers who self-reported a positive test for COVID-19 (mean = 30 days since most recent test) perform significantly worse than pre-pandemic norms on cognitive measures of processing speed, reasoning, verbal, and overall performance, but not short-term memory, suggesting domain-specific deficits. Cognitive differences are even observed in participants who did not require hospitalization. Factor analysis of health- and COVID-related questionnaires reveals two clusters of symptoms—one that varies mostly with physical symptoms and illness severity, and one with mental health. Cognitive performance is positively correlated with the global measure encompassing physical symptoms, but not the one that broadly describes mental health, suggesting that the subjective experience of “long COVID” relates to physical symptoms and cognitive deficits, especially executive dysfunction.

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Survivors of COVID-19 exhibit cognitive differences in specific domains

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Speed of processing, verbal, and reasoning are affected, but not memory function

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Performance in affected domains is linked to physical but not mental health

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These effects are observed in mild and hospitalized cases of COVID-19

Demographic and social determinants of cognitive dysfunction following hospitalization for COVID-19

BACKGROUND

Persistent cognitive symptoms have been reported following COVID-19 hospitalization. We investigated the relationship between demographics, social determinants of health (SDOH) and cognitive outcomes 6-months after hospitalization for COVID-19.

METHODS

We analyzed 6-month follow-up data collected from a multi-center, prospective study of hospitalized COVID-19 patients. Demographic and SDOH variables (age, race/ethnicity, education, employment, health insurance status, median income, primary language, living arrangements, and pre-COVID disability) were compared between patients with normal versus abnormal telephone Montreal Cognitive Assessments (t-MOCA; scores<18/22). Multivariable logistic regression models were constructed to evaluate predictors of t-MoCA.

RESULTS

Of 382 patients available for 6-month follow-up, 215 (56%) completed the t-MoCA (n = 109/215 [51%] had normal and n = 106/215 [49%] abnormal results). 14/215 (7%) patients had a prior history of dementia/cognitive impairment. Significant univariate predictors of abnormal t-MoCA included older age, ≤12 years of education, unemployment pre-COVID, Black race, and a pre-COVID history of cognitive impairment (all p < 0.05). In multivariable analyses, education ≤12 years (adjusted OR 5.21, 95%CI 2.25-12.09), Black race (aOR 5.54, 95%CI 2.25-13.66), and the interaction of baseline functional status and unemployment prior to hospitalization (aOR 3.98, 95%CI 1.23-12.92) were significantly associated with abnormal t-MoCA scores after adjusting for age, history of dementia, language, neurological complications, income and discharge disposition.

CONCLUSIONS

Fewer years of education, Black race and unemployment with baseline disability were associated with abnormal t-MoCA scores 6-months post-hospitalization for COVID-19. These associations may be due to undiagnosed baseline cognitive dysfunction, implicit biases of the t-MoCA, other unmeasured SDOH or biological effects of SARS-CoV-2.

The New Coronavirus Infection (COVID-19) and Hearing Function in Adults

In this study, we assessed the impact of COVID-19 on the hearing function in adults. A total of 161 subjects were examined, and the results of a previous audiological examination of 24 patients were reviewed. Pure tone audiometry, impedancemetry, speech audiometry in quiet and noise, the Binaural Fusion Test, the dichotic digits test, and a cognitive status examination were performed. A total of 81% of patients complained about hearing disorders, and 43% noted memory impairment. According to pure tone audiometry, 24% of the subjects had normal hearing, while 76% had some degree of hearing loss. No significant changes in hearing thresholds were found in comparison with audiological examinations performed before COVID-19. Disorder of monosyllabic words’ intelligibility in quiet was found in 33% of patients, and in 42% in noise, along with low indicators in the dichotic digits test in 54% of patients. Moreover, 71% of patients had low scores on the MoCA scale that indicated cognitive impairment. Conclusions: The deterioration of speech test scores in patients after COVID-19 can occur due to central auditory processing disorders (CAPD), memory impairment, or changes in cognitive status in general.

Neurocognitive Profile of the Post-COVID Condition in Adults in Catalonia-A Mixed Method Prospective Cohort and Nested Case-Control Study: Study Protocol

The diagnosis of the post-COVID condition is usually achieved by excluding other diseases; however, cognitive changes are often found in the post-COVID disorder. Therefore, monitoring and treating the recovery from the post-COVID condition is necessary to establish biomarkers to guide the diagnosis of symptoms, including cognitive impairment. Our study employs a prospected cohort and nested case-control design with mixed methods, including statistical analyses, interviews, and focus groups. Our main aim is to identify biomarkers (functional and structural neural changes, inflammatory and immune status, vascular and vestibular signs and symptoms) easily applied in primary care to detect cognitive changes in post-COVID cases. The results will open up a new line of research to inform diagnostic and therapeutic decisions with special considerations for cognitive impairment in the post-COVID condition.

Neurocognitive Profiles in Patients With Persisting Cognitive Symptoms Associated With COVID-19

OBJECTIVE

A subset of individuals with coronavirus disease 2019 (COVID-19) appears to develop persisting cognitive and medical symptoms. Research in the acute stages of illness, generally utilizing cognitive screening measures or case reports, suggests presence of deficits in attention and executive function. This observational study investigated cognitive functioning among individuals with persistent cognitive complaints about 5.5 months after COVID-19 infection.

METHODS

Patients with polymerase chain reaction confirmed COVID-19 and persistent cognitive complaints underwent comprehensive in-person neuropsychological evaluations. Patients with prior neurological disorders were excluded. When diagnosed, 40% required hospitalization, 15% were in an intensive care unit, 10% needed mechanical ventilation, and 10% experienced delirium.

RESULTS

This sample was predominately women (90%), White non-Hispanic (70%), with average education of 15 years. Mild cognitive deficits were seen on tests involving attention and processing speed or executive function. Seventy percent of patients were diagnosed with a mood disorder prior to COVID-19 infection. At the time of testing, 35%-40% endorsed moderate to severe mood symptoms and 85% noted significant fatigue as measured by the Fatigue Severity Scale.

CONCLUSIONS

The pattern of cognitive deficits, although mild, is consistent with prior research at the acute stage of the illness. These findings suggest that psychological factors and other persisting symptoms (e.g., sleep, fatigue) may play a significant role in subjective cognitive complaints in patients with persisting complaints post COVID-19 who did not require intensive treatment. These patients would likely benefit from resources to manage persisting or new mood symptoms and compensatory strategies for the cognitive inefficiencies they experience.

Multivariate profile and acute-phase correlates of cognitive deficits in a COVID-19 hospitalised cohort

Background

Preliminary evidence has highlighted a possible association between severe COVID-19 and persistent cognitive deficits. Further research is required to confirm this association, determine whether cognitive deficits relate to clinical features from the acute phase or to mental health status at the point of assessment, and quantify rate of recovery.

Methods

46 individuals who received critical care for COVID-19 at Addenbrooke's hospital between 10th March 2020 and 31st July 2020 (16 mechanically ventilated) underwent detailed computerised cognitive assessment alongside scales measuring anxiety, depression and post-traumatic stress disorder under supervised conditions at a mean follow up of 6.0 (± 2.1) months following acute illness. Patient and matched control (N = 460) performances were transformed into standard deviation from expected scores, accounting for age and demographic factors using N = 66,008 normative datasets. Global accuracy and response time composites were calculated (G_SScore & G_RT). Linear modelling predicted composite score deficits from acute severity, mental-health status at assessment, and time from hospital admission. The pattern of deficits across tasks was qualitatively compared with normal age-related decline, and early-stage dementia.

Findings

COVID-19 survivors were less accurate (G_SScore=-0.53SDs) and slower (G_RT=+0.89SDs) in their responses than expected compared to their matched controls. Acute illness, but not chronic mental health, significantly predicted cognitive deviation from expected scores (G_SScore (p=​​0.0037) and G_RT (p = 0.0366)). The most prominent task associations with COVID-19 were for higher cognition and processing speed, which was qualitatively distinct from the profiles of normal ageing and dementia and similar in magnitude to the effects of ageing between 50 and 70 years of age. A trend towards reduced deficits with time from illness (r∼=0.15) did not reach statistical significance.

Interpretation

Cognitive deficits after severe COVID-19 relate most strongly to acute illness severity, persist long into the chronic phase, and recover slowly if at all, with a characteristic profile highlighting higher cognitive functions and processing speed.

Funding

This work was funded by the National Institute for Health Research (NIHR) Cambridge Biomedical Research Centre (BRC), NIHR Cambridge Clinical Research Facility (BRC-1215-20014), the Addenbrooke's Charities Trust and NIHR COVID-19 BioResource RG9402. AH is funded by the UK Dementia Research Institute Care Research and Technology Centre and Imperial College London Biomedical Research Centre. ETB and DKM are supported by NIHR Senior Investigator awards. JBR is supported by the Wellcome Trust (220258) and Medical Research Council (SUAG/051 G101400). VFJN is funded by an Academy of Medical Sciences/ The Health Foundation Clinician Scientist Fellowship. The views expressed are those of the authors and not necessarily those of the NHS, the NIHR or the Department of Health and Social Care.

Changes in cognitive functioning after COVID-19: A systematic review and meta-analysis

Introduction

We conducted a systematic review and meta‐analysis of the cognitive effects of coronavirus disease 2019 (COVID‐19) in adults with no prior history of cognitive impairment.

Methods

Searches in Medline/Web of Science/Embase from January 1, 2020, to December 13, 2021, were performed following Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) guidelines.  A meta‐analysis of the Montreal Cognitive Assessment (MoCA) total score comparing recovered COVID‐19 and healthy controls was performed.

Results

Oof 6202 articles, 27 studies with 2049 individuals were included (mean age = 56.05 years, evaluation time ranged from the acute phase to 7 months post‐infection). Impairment in executive functions, attention, and memory were found in post‐COVID‐19 patients.  The meta‐analysis was performed with a subgroup of 290 individuals and showed a difference in MoCA score between post‐COVID‐19 patients versus controls (mean difference = −0.94, 95% confidence interval [CI] −1.59, −0.29; P = .0049).

Discussion

Patients recovered from COVID‐19 have lower general cognition compared to healthy controls up to 7 months post‐infection.

Neuropsychological deficits in patients with cognitive complaints after COVID-19

BACKGROUND

While much of the scientific focus thus far has been on cognitive sequelae in patients with severe COVID-19, subjective cognitive complaints are being reported across the spectrum of disease severity, with recent studies beginning to corroborate patients' perceived deficits. In response to this, the aims of this study were to (1) explore the frequency of impaired performance across cognitive domains in post-COVID patients with subjective complaints and (2) uncover whether impairment existed within a single domain or across multiple.

METHODS

Sixty-three patients with subjective cognitive complaints post-COVID were assessed with a comprehensive protocol consisting of various neuropsychological tests and mood measures. Cognitive test performance was transformed into T scores and classified based on recommended guidelines. After performing a principal component analysis to define cognitive domain factors, distributions of test scores within and across domains were analyzed.

RESULTS

Results revealed pervasive impact on attention abilities, both as the singularly affected domain (19% of single-domain impairment) as well as coupled with decreased performance in executive functions, learning, and long-term memory. These salient attentional and associated executive deficits were largely unrelated to clinical factors such as hospitalization, disease duration, biomarkers, or affective measures.

DISCUSSION

These findings stress the importance of comprehensive evaluation and intervention to address cognitive sequelae in post-COVID patients of varying disease courses, not just those who were hospitalized or experienced severe symptoms. Future studies should investigate to what extent these cognitive abilities are recuperated over time as well as employ neuroimaging techniques to uncover underlying mechanisms of neural damage.

Outcomes in post-acute sequelae of COVID-19 (PASC) at 6 months post-infection Part 1: Cognitive functioning

OBJECTIVE

Long-term cognitive sequelae of COVID-19 have not been extensively studied. This study provides initial results on cognitive outcomes in Post-Acute Sequelae of COVID-19 (PASC).Participants and Methods: This study examined 53 consecutive outpatients diagnosed with COVID-19. Four participants were excluded due to performance validity test failure. All participants had positive COVID-19 tests, reported cognitive concerns, and completed neuropsychological tests to assess performance validity, attention/working memory, processing speed, memory, language, visual-spatial, executive functioning, motor, and emotional functioning. The sample was mostly white (89.8%), female (83.7%), and never hospitalized (69.4%) for COVID-19.

RESULTS

Analyses indicated no mean scores in the Impaired range (>2 standard deviations [SD] below normative mean) on objective cognitive testing and a low base rate of Impaired test scores. Higher (>20%) base rates of Borderline performance (1-2 SDs below normative mean) were found on some measures. There was also evidence for frequently elevated mean scores on mood measures which correlated with some cognitive measures and the number of Borderline scores per participants.

CONCLUSIONS

The results were noteworthy for infrequent Impaired scores, and significant correlations between cognition and mood/anxiety measures, but not between cognitive performance and premorbid vascular risk factors, psychiatric diagnoses, or COVID-19 disease severity. Results suggest that psychological distress was prominent in PASC and related to objective cognitive performance, but objective cognitive performance was unrelated to cognitive complaints. Other contributing factors may include fatigue/sleep issues. Neurologically based cognitive deficits were not suggested by the results.During the COVID-19 pandemic, researchers and clinicians have gained considerable knowledge of the SARS-CoV-2 virus that causes the COVID-19 illness. Research has implicated COVID-19 in a variety of neurological and psychiatric issues (Taquet et al., 2021) including stroke, depression/anxiety, and more rarely intracranial hemorrhage and psychotic disorders. Further, various vascular risk factors such as hypertension, diabetes, hyperlipidemia, and obstructive sleep apnea (OSA) have been associated with more severe COVID-19 symptoms (Bauer et al., 2021; Luk et al., 2021; Mishra et al., 2020; Saxena et al., 2021). Additionally, while many patients recover from COVID-19 in a few weeks, a substantial number continue to experience physical (e.g., fatigue, shortness of breath, cough, palpitations) and cognitive (e.g., "brain fog", concentration and memory complaints) symptoms for a considerable period (Raveendran et al., 2021). It has also been suggested that patients themselves, via social media, contributed to reifying the phenomenon of "Long COVID-19" or post-acute sequelae of SARS-CoV-2 infection (PASC; Callard & Perego, 2021). However, very limited research exists that directly investigates the cognitive sequelae of COVID-19 infection, particularly in the long term. The current study aims to address this limitation in the literature.

Outcomes in post-acute sequelae of COVID-19 (PASC) at 6 months post-infection part 2: Psychological functioning

Limited research investigating the long-term psychological and emotional correlates of COVID-19 infection has been completed. The current study begins to address this limitation in patients experiencing Post-Acute Sequelae SARS-CoV-2 (PASC; e.g. "Long COVID").

Participants were 43 consecutive neuropsychological outpatients diagnosed with PASC and who completed the Personality Assessment Inventory (PAI). The sample was predominantly female (n = 36) and white (n = 32). Effect sizes compared to the normative mean T scores and base rates of elevated (T > 69) scores were calculated.

PAI scales measuring somatic preoccupation and depression had large effect sizes and the highest base rates of scale elevations, with the mean T score at approximately the normative cutoff for clinical significance (T = 70). The Schizophrenia Thought Disorder subscale (SCZ-T) also had a large effect size and high base rate of elevation, likely reflecting cognitive concerns. Scales measuring anxiety had medium effect sizes. The other PAI scales generally had small to negligible effect sizes. There were no significant differences between hospitalized and non-hospitalized participants on the PAI.

Overall, PAI scales measuring psychological distress, particularly somatic preoccupation and depression, were the most frequently elevated in the participants. The specific reasons for somatic preoccupation could not be determined in this study. Potential explanations include a vulnerability to distress in Long COVID patients, premorbid somatic preoccupation perhaps motivating these patients to seek clinical attention, or socioenvironmental factors leading some COVID patients to be somatically preoccupied with minor physiological changes and attribute those changes to COVID-19.

Cognitive consequences of COVID-19: results of a cohort study from South America

BACKGROUND

Neurological and psychiatric manifestations associated with SARS-CoV-2 infection have been reported throughout the scientific literature. However, studies on post-COVID cognitive impairment in people with no previous cognitive complaint are scarce.

OBJECTIVE

We aim to investigate the impact of COVID-19 on cognitive functions in adults without cognitive complaints before infection and to study cognitive dysfunction according to disease severity and cognitive risk factors.

METHODS

Forty-five post-COVID-19 patients and forty-five controls underwent extensive neuropsychological evaluation, which assessed cognitive domains such as memory, language, attention, executive functions, and visuospatial skills, including psychiatric symptomatology scales. Data were collected on the severity of infection, premorbid medical conditions, and functionality for activities of daily living before and after COVID-19.

RESULTS

Significant differences between groups were found in cognitive composites of memory (p=0.016, Cohen's d= 0.73), attention (p<0.001, Cohen's d=1.2), executive functions (p<0.001, Cohen's d=1.4), and language (p=0.002, Cohen's d=0.87). The change from premorbid to post-infection functioning was significantly different between severity groups (WHODAS, p=0.037). Self-reported anxiety was associated with the presence of cognitive dysfunction in COVID-19 subjects (p=0.043).

CONCLUSION

Our results suggest that the presence of cognitive symptoms in post-COVID-19 patients may persist for months after disease remission and argue for the inclusion of cognitive assessment as a protocolized stage of the post-COVID examination. Screening measures may not be sufficient to detect cognitive dysfunction in post-COVID-19 patients.

Post-Acute COVID-19 Syndrome for Anesthesiologists: A Narrative Review and a Pragmatic Approach to Clinical Care

Post-acute coronavirus disease 2019 (COVID-19) syndrome is a novel, poorly understood clinical entity with life-impacting ramifications. Patients with this syndrome, also known as "COVID-19 long-haulers," often present with nonspecific ailments involving more than one body system. The most common complaints include dyspnea, fatigue, brain fog, and chest pain. There currently is no single agreed-upon definition for post-acute COVID-19 syndrome, but most agree that criterion for this syndrome is the persistence of mental and physical health consequences after initial infection. Given the millions of acute infections in the United States over the course of the pandemic, perioperative providers will encounter these patients in clinical practice in growing numbers. Symptoms of the COVID-19 long-haulers should not be minimized, as these patients are at higher risk for postoperative respiratory complications and perioperative mortality for up to seven weeks after initial illness. Instead, a cautious multidisciplinary preoperative evaluation should be performed. Perioperative care should be viewed through the prism of best practices already in use, such as avoidance of benzodiazepines in patients with cognitive impairment and use of lung-protective ventilation. Recommendations especially relevant to the COVID-19 long-haulers include assessment of critical care myopathies and neuropathies to determine suitable neuromuscular blocking agents and reversal, preoperative workup of insidious cardiac or pulmonary pathologies in previously healthy patients, and, thorough medication review, particularly of anticoagulation regimens and chronic steroid use. In this article, the authors define the syndrome, synthesize the available scientific evidence, and make pragmatic suggestions regarding the perioperative clinical care of COVID-19 long-haulers.

Psychiatric and neuropsychiatric sequelae of COVID-19 - A systematic review

It has become evident that coronavirus disease 2019 (COVID-19) has a multi-organ pathology that includes the brain and nervous system. Several studies have also reported acute psychiatric symptoms in COVID-19 patients. An increasing number of studies are suggesting that psychiatric deficits may persist after recovery from the primary infection. In the current systematic review, we provide an overview of the available evidence and supply information on potential risk factors and underlying biological mechanisms behind such psychiatric sequelae. We performed a systematic search for psychiatric sequelae in COVID-19 patients using the databases PubMed and Embase. Included primary studies all contained information on the follow-up period and provided quantitative measures of mental health. The search was performed on June 4th 2021. 1725 unique studies were identified. Of these, 66 met the inclusion criteria and were included. Time to follow-up ranged from immediately after hospital discharge up to 7 months after discharge, and the number of participants spanned 3 to 266,586 participants. Forty studies reported anxiety and/or depression, 20 studies reported symptoms- or diagnoses of post-traumatic stress disorder (PTSD), 27 studies reported cognitive deficits, 32 articles found fatigue at follow-up, and sleep disturbances were found in 23 studies. Highlighted risk factors were disease severity, duration of symptoms, and female sex. One study showed brain abnormalities correlating with cognitive deficits, and several studies reported inflammatory markers to correlate with symptoms. Overall, the results from this review suggest that survivors of COVID-19 are at risk of psychiatric sequelae but that symptoms generally improve over time.

Auditory Disturbances and SARS-CoV-2 Infection: Brain Inflammation or Cochlear Affection? Systematic Review and Discussion of Potential Pathogenesis

Patients affected by COVID-19 present a series of different symptoms; despite some of these are common, other less likely appear. Auditory symptoms seem to be less frequent, maybe because rarer or, alternatively, because they are underestimated during the clinical investigation. The hearing impairment might be related to the central or peripheral involvement of the auditory pathways; in particular, the likelihood of thrombosis might be one of the causes. To date, the prevalence of auditory symptoms such as sudden or progressive sensorineural hearing loss and tinnitus is unclear in COVID-19 patients. However, their presence might be an early sign of thrombosis or spread of the infection into the brain. In this systematic review of the literature we investigated the presence of auditory symptoms in COVID-19 patients and discussed their potential origin and causal relationship with SARS-CoV-2. Results showed that, despite rarely, auditory impairment can appear in patients with COVID-19 and should always be investigated for an early treatment and potential indicator of involvement of the central nervous system.

Post-covid-19 neurological syndromes

The article highlights the pathogenesis, clinical manifestations of lesions of the central and peripheral nervous system that have arisen or persist in patients in the postcoid period (Long-COVID-19). Their correct assessment, the use of effective methods of complex treatment, targeted neurorehabilitation contribute to the reversibility of functional disorders, prevention, reduction of disability, improvement of quality of life indicators, prevention of the progression of cognitive, emotional, behavioral disorders initiated by SARS-CoV-2.

Association Between Psychological Distress, Cognitive Complaints, and Neuropsychological Status After a Severe COVID-19 Episode: A Cross-Sectional Study

Background: Cognitive complaints are frequent after COVID-19 but their clinical determinants are poorly understood. This study aimed to explore the associations of objective cognitive performances and psychological distress with cognitive complaints in COVID-19 survivors. Materials and Methods: Patients previously hospitalized for COVID-19 in a university hospital during the first wave of COVID-19 pandemic in France were followed-up at 1 month after their admission. Cognitive complaints were self-reported and standardized instruments were used to assess neuropsychological status (Digit Symbol Substitution Test, Semantic Verbal Fluency Test, Mini Mental Status Examination) and psychological distress (Hospital Anxiety and Depression Scale, HADS). Multivariable analyses were adjusted for age, sex, admission in intensive care unit (ICU) and need for oxygen and C-reactive protein. Results: One hundred patients (34% women, median age: 60 years [interquartile range: 49-72)] completed the neuropsychological assessment at follow-up. In multivariable analyses, cognitive complaints at 1-month were associated with greater HADS score (OR for one interquartile range: OR: 1.96, 95% CI: 1.08-3.57) and older age (OR: 1.05, 95% CI: 1.01-1.09) and, negatively, with admission in ICU (OR: 0.22, 95% CI: 0.05-0.90). In contrast, none of the objective neuropsychological test scores was significantly associated with cognitive complaints. Exploratory analysis showed that cognitive complaints were associated with both anxiety and depressive symptoms. Discussion: These preliminary results suggest that cognitive complaints at 1 month after a hospitalization for COVID-19 are associated with psychological distress, independently of objective neuropsychological status. Anxiety and depression symptoms should be systematically screened in patients presenting with cognitive complaints after a severe COVID-19 episode.