Trajectory of cognitive impairments over 1 year after COVID-19 hospitalisation: Pattern, severity, and functional implications

Optimization of a panel of behavioral tests for use in containment using a golden Syrian hamster model

Golden Syrian hamsters are an often-overlooked model in behavioral testing. While previously utilized for research examining circadian rhythms and mammalian reproduction, they are less common than murine models in both infectious disease and behavioral studies. However, coronavirus disease-19 (COVID-19) quickly pushed hamster modeling to the forefront due to its myriad of advantages over mice in recapitulating human pathology and transmission. At least 10 % of COVID-19 survivors suffer from post-acute sequelae of COVID-19 (PASC), a collection of some 200 sequelae with neurologic sequelae (neuro-PASC) presenting with potentially debilitating symptomology. This presents a clear need for a small animal model that recapitulates human disease with the ability to assess any potential long term neurological changes. We adapted and optimized a panel of behavioral tests from previously accepted murine models utilizing the golden Syrian hamster model for use within biocontainment facilities. Our panel includes grip strength, Porsolt forced swim, and novel object recognition testing to measure muscle fatigue or weakness, depression, and memory loss or cognitive impairment, respectively. Apart from severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), this panel of tests is applicable to other pathogens that cause neurologic sequelae, such as Nipah or eastern equine encephalitis viruses, or any other model systems that require the use of hamsters. In this manuscript, we detail the methods for each of these three behavioral tests, how to interpret and analyze the resulting data, and emphasize additional factors for consideration. We also provide baseline data for both male and female golden Syrian hamsters.

Persistent neuropsychological deficits in recovered COVID-19 patients: Correlations with disease biomarkers

OBJECTIVE

Cognitive impairment, including deficits in attention, memory, executive function, and processing speed, is common in post-COVID-19 conditions, though language performance remains less studied. The present study examined the long-term effects of COVID-19 condition on cognition and language - communication, and its associations with disease severity, Body Mass Index (BMI), inflammatory markers, and quality of life.

METHOD

Nighty eight Greek participants under 65 years of age were recruited for this study. Forty-seven participants were allocated in the COVID-19 group and 51 served as cognitively healthy controls. The COVID-19 group was categorized by disease severity and long COVID status. Assessments occurred 12 weeks post-infection, with 12 patients reevaluated after another 12 weeks. Neurocognitive tests included ABCD-II, verbal fluency, CCT, SDMT, and Euro QoL EQ-5D. Blood samples were analyzed for inflammatory markers.

RESULTS

Covid-19 survivors experienced significant cognitive deficits compared to healthy controls, particularly in processing speed, memory, and verbal fluency. Long COVID patients showed notably lower scores in processing speed and QoL, compared to those without Long COVID. However, no significant differences were observed between groups on episodic memory and executive functions tasks. Cognitive deficits were associated with biomarkers such as d-dimers and C-Reactive protein, with elevated d-dimers linked to poorer performance on generative drawing and cognitive flexibility. Higher education served as a protective factor, and was associated with higher scores in tasks such as story retelling, confrontation naming, generative drawing and reading comprehension. Older age and higher Body Mass Index were associated with poorer cognitive performance, especially on processing speed. Sex appears to influence language comprehension outcomes, with males exhibiting enhanced performance on the reading comprehension-sentence task. Disease severity negatively affected performance on the Symbol Digit Modalities Test and generative naming, indicating that greater severity was linked to poorer outcomes in these domains. Follow-up evaluations of recovered COVID-19 patients revealed significant improvements in processing speed and recall, suggesting partial recovery in these areas, although some deficits persisted over time.

CONCLUSION

The study supports findings that the prolonged effects of COVID-19 markedly impaired neurocognitive functions in recovering patients, especially those with severe or long COVID syndrome. Moreover, while several cognitive domains may improve over time, many other domains remain impaired and vulnerable.

Long-term cognitive functioning following COVID-19: Negligible neuropsychological changes over time

Objective: Objective cognitive impairment has been shown in a minority of hospitalized COVID-19 patients, and longitudinal studies with a relatively long follow-up duration are scarce. We sought to investigate the presence and long-term change of objective cognitive functioning. Method: Forty-six initially hospitalized (18 ± 19 days) COVID-19 survivors (male/female: 30/16; age: 61 ± 11) underwent extensive neuropsychological assessment (including performance validity) approximately 1 (T1) and 2.5 years (T2) post-infection. Cognitive domains assessed were: memory, attention, executive functioning, processing speed, and language (n = 14 (sub)tests). We used normative data to derive age, sex, and education-adjusted T-scores (T ≤ 35 [≤-1.5SD], deficit cut-off). Repeated measures AN(C)OVAs were used to investigate cognitive functioning over time. Results: Mean neuropsychological performance (n = 14 tests) was within normal range at both timepoints, and number of individuals with objective cognitive deficits ranged from 0-20% (T1), and 2-22% (T2). Number of subjective cognitive complaints remained unchanged. A minority (17%) showed objective cognitive deficits on ≥2 tests at both 1 and 2.5 years post-infection, but not consistently within one cognitive domain. Longitudinal analyses on the total sample showed improvement in performance over time on phonemic fluency (p<.001), but stable cognitive performance on all other tests, independent of prior comorbidities, subjective cognitive complaints, depressive symptoms, and ICU admission. Conclusions: There were no consistent objective cognitive deficits or major cognitive disorders years after SARS-CoV-2 infection in the majority of cases. Neuropsychological functioning remained essentially unchanged over time. Future larger longitudinal studies are necessary to unravel COVID-19-related cognitive phenotypes of persisting deficits and how these can be modulated.

Subjective cognitive, psychiatric, and fatigue symptoms two years after COVID-19: A prospective longitudinal cohort study

Introduction

COVID-19 survivors may present with cognitive and psychiatric symptoms long after the acute phase of SARS-CoV-2 infection.

Objectives

To determine subjective cognitive, psychiatric, and fatigue symptoms two years after COVID-19, and their change from six months to two years.

Methods

We assessed three COVID-19 patient groups of different acute disease severity (ICU-treated, ward-treated, home-isolated) concerning subjective cognitive functioning (AB Neuropsychological Assessment Schedule), anxiety (Generalised Anxiety Disorder 7), depression (Patient Health Questionnaire 9), post-traumatic stress (Impact of Event Scale 6), and fatigue (Multidimensional Fatigue Inventory) with a mailed questionnaire approximately two years after acute COVID-19. We compared the results with those obtained six months after the acute disease. We studied whether any change emerged in the scores of symptomatic patients between six- and 24-month follow-ups.

Results

Two years post-COVID-19, 58 ICU-treated, 35 ward-treated, and 28 home-isolated patients responded to the questionnaire. Subjective cognitive symptoms and fatigue emerged as the most common problems occurring in 30.6 and 35.5% of patients, respectively. In patients with clinically significant symptoms at six months, symptom scores for depression, anxiety, and post-traumatic stress decreased at two years.

Conclusions

Two years after COVID-19, particularly self-reported cognitive symptoms and fatigue remained clinically significant, but also some recovery was evident in depression, anxiety, and post-traumatic stress.

Cognitive reserve moderates the effect of COVID-19 on cognition: A systematic review and meta-analysis of individual participant data

Elucidating the factors that mitigate the effects of COVID-19 on cognitive function offers important insights for public health policy and intervention. This systematic review and individual participant data (IPD) meta-analysis assesses cognitive reserve (CR) as a potential moderator of post-COVID-19 cognitive dysfunction (PCCD). Under PRISMA-IPD guidelines, data searches were conducted via PubMed, PsycINFO, Scopus, and Embase, up to January 2023. Eligible studies included at least one cognitive assessment, CR proxy, and disease severity indicator. Of 5604 studies, 87 were eligible (10,950 COVID-19 cases; 78,305 controls), and IPD was obtained for 29 datasets (3919 COVID-19 cases; 8267 controls). Three-level random-effects meta-analyses indicated that CR had a moderate positive association (rsp =.29), and COVID-19 severity had a small negative association (rsp = -.07) with cognitive outcomes. These effects were moderated by a significant within-study interaction. Cognitive deficits following COVID-19 were 33 % smaller among high CR individuals, and 33 % greater among low CR individuals, relative to those with average CR. Population-based initiatives promoting reserve-building behaviors may alleviate the PCCD-related public health burden. REVIEW REGISTRATION: PROSPERO registration number: CRD42022360670.

Cognitive Sequelae of COVID-19: Mechanistic Insights and Therapeutic Approaches

BACKGROUND

The COVID-19 pandemic has left an indelible mark on the world, with mounting evidence suggesting that it not only posed acute challenges to global healthcare systems but has also unveiled a complex array of long-term consequences, particularly cognitive impairment (CI). As the persistence of post-COVID-19 neurological syndrome could evolve into the next public health crisis, it is imperative to gain a better understanding of the intricate pathophysiology of CI in COVID-19 patients and viable treatment strategies.

METHODS

This comprehensive review explores the pathophysiology and management of cognitive impairment across the phases of COVID-19, from acute infection to Long-COVID, by synthesizing findings from clinical, preclinical, and mechanistic studies to identify key contributors to CI, as well as current therapeutic approaches.

RESULTS

Key mechanisms contributing to CI include persistent neuroinflammation, cerebrovascular complications, direct neuronal injury, activation of the kynurenine pathway, and psychological distress. Both pharmacological interventions, such as anti-inflammatory therapies and agents targeting neuroinflammatory pathways, and non-pharmacological strategies, including cognitive rehabilitation, show promise in addressing these challenges. Although much of the current evidence is derived from preclinical and animal studies, these findings provide foundational insights into potential treatment approaches.

CONCLUSION

By synthesizing current knowledge, this review highlights the importance of addressing COVID-19-related cognitive impairment and offers actionable insights for mitigation and recovery as the global community continues to grapple with the pandemic's long-term impact.

Cognitive domains affected post-COVID-19; a systematic review and meta-analysis

BACKGROUND AND PURPOSE

This review aims to characterize the pattern of post-COVID-19 cognitive impairment, allowing better prediction of impact on daily function to inform clinical management and rehabilitation.

METHODS

A systematic review and meta-analysis of neurocognitive sequelae following COVID-19 was conducted, following PRISMA-S guidelines. Studies were included if they reported domain-specific cognitive assessment in patients with COVID-19 at >4 weeks post-infection. Studies were deemed high-quality if they had >40 participants, utilized healthy controls, had low attrition rates and mitigated for confounders.

RESULTS

Five of the seven primary Diagnostic and Statistical Manual of Mental Disorders (DSM-5) cognitive domains were assessed by enough high-quality studies to facilitate meta-analysis. Medium effect sizes indicating impairment in patients post-COVID-19 versus controls were seen across executive function (standardised mean difference (SMD) -0.45), learning and memory (SMD -0.55), complex attention (SMD -0.54) and language (SMD -0.54), with perceptual motor function appearing to be impacted to a greater degree (SMD -0.70). A narrative synthesis of the 56 low-quality studies also suggested no obvious pattern of impairment.

CONCLUSIONS

This review found moderate impairments across multiple domains of cognition in patients post-COVID-19, with no specific pattern. The reported literature was significantly heterogeneous, with a wide variety of cognitive tasks, small sample sizes and disparate initial disease severities limiting interpretability. The finding of consistent impairment across a range of cognitive tasks suggests broad, as opposed to domain-specific, brain dysfunction. Future studies should utilize a harmonized test battery to facilitate inter-study comparisons, whilst also accounting for the interactions between COVID-19, neurological sequelae and mental health, the interplay between which might explain cognitive impairment.

Assessment of cognitive and psychiatric disturbances in people with post-COVID-19 condition: a cross-sectional observational study

OBJECTIVE

Cognitive and psychiatric symptoms have been increasingly reported after severe acute respiratory syndrome coronavirus 2 infection, developing soon after infection and possibly persisting for several months. We aimed to study this syndrome and start implementing strategies for its assessment.

METHODS

Consecutive patients, referred by the infectious disease specialist because of cognitive complaints after COVID-19, were neurologically evaluated. Neurological evaluation included a cognitive screening test (Montreal Cognitive Assessment, MoCA). Moreover, patients were invited to fill out a general symptom questionnaire and a self-administered multidimensional assessment of psychiatric symptoms, followed by a full psychiatric assessment if scores were above validated cutoffs.

RESULTS

Of 144 referred patients, 101 (mean age 55.2±13.1, 63.4% females) completed the cognitive screening and the self-administered psychiatric questionnaire. Acute infection severity was low for most patients and the most common persisting symptoms were fatigue (92%), sleep problems (69.5%), and headache (52.4%). MoCA outlined cognitive deficits in ≥1 cognitive domain in 34% of patients, mainly in memory and attention. About 60% of patients presented depressive, anxiety, or stress-related symptoms. Psychiatric scale scores significantly correlated with overall symptom burden and MoCA score. No significant correlation was found between MoCA scores and overall symptom burden.

CONCLUSION

We hypothesize that persistent cognitive complaints after COVID-19 might reflect a concomitant or reactive psychopathological condition, possibly coupled with an infection-related impact on cognitive functions. The application of a combined neurological and psychiatric assessment seems crucial to appraise the nature of post-COVID-19 condition.

Cognitive outcomes and psychological symptoms in an Italian cohort with post-acute COVID-19 condition (PACC)

Background

We aim to investigate the proportion of patients (pts) with long-term cognitive outcomes (CO) of PACC and identify associated features.

Methods

We assessed participants through a neuropsychological assessment. The chi-square test was used for comparisons according with time of NPA (within or beyond 6 months since COVID19) and with previously hospitalization status (hospitalized patients, PH; not hospitalized patients, nPH).

Results

520 participants: mean age 54 years (SD 12), 53 % female, 14 years of education (SD 3.4), 35 % with >1 comorbidity, 48 % previously hospitalized. Overall, we found CO in 89 % of pts, in particular 88 % evaluated in w6M and 89 % in b6M (p = 0.801) while 90 % and 87 % in nPH and PH, respectively (p = 0.239). By fitting multivariable analysis, PH for COVID19 and female gender were associated with an increased risk of an altered PSQI [Odd Ratio, OR 2.48, 95 % CI 1.54 to 3.99, p < 0.001 and OR 2.59, 95 % CI 1.60 to 4.17, p < 0.001, respectively) and BAI [F vs M: OR 1.67, 95 % CI 1.16 to 2.40, p = 0.005).

Conclusions

We show a substantial proportion of PACC-CO; hospitalization leads to impaired memory, anxiety and sleep disorders. Women seem to be at higher risk for anxious-depressive symptoms and worse sleep quality than men.

Exploring cognitive impairments and the efficacy of phosphatidylcholine and computer-assisted cognitive training in post-acute COVID-19 and post-acute COVID-19 Vaccination Syndrome

Purpose

The COVID-19 pandemic has led to millions of confirmed cases worldwide, resulting in numerous deaths and hospitalizations. Long-term symptoms after infection or vaccination, known as Post-acute COVID-19 Syndrome (PACS) or Post-acute COVID-19 Vaccination Syndrome (PACVS), present a challenge for the healthcare system. Among the various neurological symptoms, cognitive impairments are frequently observed in PACS/PACVS patients. This study aimed to understand cognitive deficits in PACS/PACVS patients and evaluated potential treatment options, including phosphatidylcholine and computer-assisted cognitive training (CCT).

Methods

The Neuro-COVID Outpatient Clinic at Evangelic Hospital Vienna evaluated n = 29 PACS/PACVS patients from May 2023 to October 2023. Enrolled patients were divided into three therapy schemes: Group A received phosphatidylcholine, B received phosphatidylcholine plus access to a computer-assisted cognitive training program, and C (divided into two subgroups) served as a control group. Cognitive impairments were evaluated in multiple assessments (initial and during therapy) using the COGBAT test. Simultaneously, an assessment of the quality of life was conducted using the WHOQOL-BREF.

Results

Primary cognitive impairments, especially attentional deficits were notably evident compared to the general population. While all treatment groups showed cognitive improvement (significant or with a positive trend, but without reaching the level of statistical significance) after therapy, no significant interaction was found between assessment time points and treatment schemes for overall cognitive performance, attention, memory, and executive functions, suggesting consistency across the groups. The WHOQOL-BREF primarily demonstrated deficits in the domains of physical health and psychological well-being.

Conclusion

This study examined the impact of PACS/PACVS on cognitive performance and evaluated phosphatidylcholine and CCT as potential treatment options. Patients with PACS/PACVS showed notable cognitive deficits, especially in the domain attention. While the effectiveness of phosphatidylcholine and CCT in treating cognitive deficits was inconclusive, the study indicated the possibility of spontaneous remission of cognitive deficits in PACS/PACVS.

Evolving trends in neuropsychological profiles of post COVID-19 condition: A 1-year follow-up in individuals with cognitive complaints

Cognitive difficulties are reported as lasting sequelae within post COVID-19 condition. However, the chronicity of these difficulties and related factors of fatigue, mood, and perceived health have yet to be fully determined. To address this, the current longitudinal study aimed to clarify the trends of cognitive test performance and cognitive domain impairment following COVID-19 onset, and whether hospitalization influences outcomes. 57 participants who reported subjective cognitive difficulties after confirmed COVID-19 infection were assessed at baseline (~6 months post COVID-19) and follow-up (~15 months later) visits. Assessments included measures across multiple cognitive domains and self-report questionnaires of fatigue, mood, and overall health. Analyses were conducted in three stages: at the test score level (raw and adjusted scores), at the cognitive domain level, and stratified by hospitalization status during infection. Results at the test-score level indicate that cognitive performance remains relatively stable across assessments at the group level, with no significant improvements in any adjusted test scores at follow-up. Cognitive domain analyses indicate significant reductions in attention and executive functioning impairment, while memory impairment is slower to resolve. On self-report measures, there was a significant improvement in overall health ratings at follow-up. Finally, those hospitalized during infection performed worse on timed cognitive measures across visits and accounted for a larger proportion of cases with short-term and working memory impairment at follow-up. Overall, our findings indicate that cognitive difficulties persist both at test score and cognitive domain levels in many cases of post COVID-19 condition, but evidence suggests some improvement in global measures of attention, executive functioning and overall self-rated health. Furthermore, an effect of hospitalization on cognitive symptoms post COVID-19 may be more discernible over time.

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

BACKGROUND

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

METHOD

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

RESULTS

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

CONCLUSIONS

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

In-Hospital Delirium and Disability and Cognitive Impairment After COVID-19 Hospitalization

Importance

Older adults who are hospitalized for COVID-19 are at risk of delirium. Little is known about the association of in-hospital delirium with functional and cognitive outcomes among older adults who have survived a COVID-19 hospitalization.

Objective

To evaluate the association of delirium with functional disability and cognitive impairment over the 6 months after discharge among older adults hospitalized with COVID-19.

Design, Setting, and Participants

This prospective cohort study involved patients aged 60 years or older who were hospitalized with COVID-19 between June 18, 2020, and June 30, 2021, at 5 hospitals in a major tertiary care system in the US. Follow-up occurred through January 11, 2022. Data analysis was performed from December 2022 to February 2024.

Exposure

Delirium during the COVID-19 hospitalization was assessed using the Chart-based Delirium Identification Instrument (CHART-DEL) and CHART-DEL-ICU.

Main Outcomes and Measures

Primary outcomes were disability in 15 functional activities and the presence of cognitive impairment (defined as Montreal Cognitive Assessment score <22) at 1, 3, and 6 months after hospital discharge. The associations of in-hospital delirium with functional disability and cognitive impairment were evaluated using zero-inflated negative binominal and logistic regression models, respectively, with adjustment for age, month of follow-up, and baseline (before COVID-19) measures of the respective outcome.

Results

The cohort included 311 older adults (mean [SD] age, 71.3 [8.5] years; 163 female [52.4%]) who survived COVID-19 hospitalization. In the functional disability sample of 311 participants, 49 participants (15.8%) experienced in-hospital delirium. In the cognition sample of 271 participants, 31 (11.4%) experienced in-hospital delirium. In-hospital delirium was associated with both increased functional disability (rate ratio, 1.32; 95% CI, 1.05-1.66) and increased cognitive impairment (odds ratio, 2.48; 95% CI, 1.38-4.82) over the 6 months after discharge from the COVID-19 hospitalization.

Conclusions and Relevance

In this cohort study of 311 hospitalized older adults with COVID-19, in-hospital delirium was associated with increased functional disability and cognitive impairment over the 6 months following discharge. Older survivors of a COVID-19 hospitalization who experience in-hospital delirium should be assessed for disability and cognitive impairment during postdischarge follow-up.

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.

Long-term findings on working memory neural dynamics in healthcare workers after mild COVID-19

OBJECTIVE

Understanding the long-term impact of Coronavirus Disease 2019 (COVID-19) on cognitive function, even in mild cases, is critical to the well-being of individuals, especially for healthcare workers who are at increased risk of exposure to the virus. To the best of our knowledge, the electrophysiological activity underlying cognitive functioning has not yet been explored.

METHODS

Seventy-seven healthcare workers took part in the study (43 with mild infection about one year before the study and 34 uninfected). To assess cognitive status, event-related potentials (ERPs) and behavioural responses were recorded while participants performed a working memory task.

RESULTS

COVID-19 participants exhibited a distinct neural pattern with lower parieto-occipital N1 amplitudes and higher frontal P2 amplitudes as compared to non-infected healthcare workers. We found no behavioural differences (reaction times and error rates) in working memory functioning between groups.

CONCLUSIONS

This neural pattern suggests the presence of a decrement of processing resources linked to the encoding of sensory information (N1), followed by the enhanced of the P2 response which could be interpreted as the activation of compensation mechanism in COVID-19 participants.

SIGNIFICANCE

The current findings point out that ERPs could serve as valuable neural indices for detecting distinctive patterns in working memory functioning of COVID-19 participants, even in mild cases. However, further research is required to precisely ascertain the long-term cognitive effects of COVID-19 beyond one-year post-infection.

Neurocognitive Changes in Patients with Post-COVID Depression

Background: Depression and cognitive impairment are recognized complications of COVID-19. This study aimed to assess cognitive performance in clinically diagnosed post-COVID depression (PCD, n = 25) patients using neuropsychological testing. Methods: The study involved 71 post-COVID patients with matched control groups: recovered COVID-19 individuals without complications (n = 18) and individuals without prior COVID-19 history (n = 19). A post-COVID depression group (PCD, n = 25) was identified based on psychiatric diagnosis, and a comparison group (noPCD, n = 46) included participants with neurological COVID-19 complications, excluding clinical depression. Results: The PCD patients showed gender-dependent significant cognitive impairment in the MoCA, Word Memory Test (WMT), Stroop task (SCWT), and Trail Making Test (TMT) compared to the controls and noPCD patients. Men with PCD showed worse performances on the SCWT, in MoCA attention score, and on the WMT (immediate and delayed word recall), while women with PCD showed a decline in MoCA total score, an increased processing time with less errors on the TMT, and worse immediate recall. No differences between groups in Sniffin's stick test were found. Conclusions: COVID-related direct (post-COVID symptoms) and depression-mediated (depression itself, male sex, and severity of COVID-19) predictors of decline in memory and information processing speed were identified. Our findings may help to personalize the treatment of depression, taking a patient's gender and severity of previous COVID-19 disease into account.

[Interaction of somatic findings and psychiatric symptoms in COVID-19. A scoping review]

An infection with SARS-CoV‑2 can affect the central nervous system, leading to neurological as well as psychiatric symptoms. In this respect, mechanisms of inflammation seem to be of much greater importance than the virus itself. This paper deals with the possible contributions of organic changes to psychiatric symptomatology and deals especially with delirium, cognitive symptoms, depression, anxiety, posttraumatic stress disorder and psychosis. Processes of neuroinflammation with infection of capillary endothelial cells and activation of microglia and astrocytes releasing high amounts of cytokines seem to be of key importance in all kinds of disturbances. They can lead to damage in grey and white matter, impairment of cerebral metabolism and loss of connectivity. Such neuroimmunological processes have been described as a organic basis for many psychiatric disorders, as affective disorders, psychoses and dementia. As the activation of the glia cells can persist for a long time after the offending agent has been cleared, this can contribute to long term sequalae of the infection.

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.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

The effects of COVID-19 infection on working memory: a systematic review

BACKGROUND

Studies demonstrate that people who have been infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19, have experienced cognitive dysfunction, including working memory impairment, executive dysfunction, and decreased concentration. This review aimed to explore the incidence of working memory impairment and possible concomitant symptoms in the acute phase (< 3 months) and chronic phase (> 6 months) of COVID-19.

METHODS

We conducted a systematic review of the following databases for inception: MEDLINE via Pub Med, Cochrane EMBASE, and Web of Science electronic databases. The search strategy was comprised of all the observational studies with COVID-19 patients confirmed by PCR or serology who were infected by SARS-CoV-2 with no previous cognitive impairment. This review protocol was recorded on PROSPERO with registration number CRD 42023413454.

RESULTS

A total of 16 studies from 502 retrieved articles were included. COVID-19 could cause a decline in working memory ability, the results showed that 22.5-55% of the people suffered from working memory impairment in the acute phase (< 3 months) of COVID-19, at 6 months after SARS-CoV2 infection, the impairment of working memory caused by COVID-19 still existed, the prevalence was about 6.2-10%, and 41.1% of the patients had a slight decrease in working memory or a negative change in the boundary value. Moreover, concomitant symptoms could persist for a long time. To some extent, the performance of working memory was affected by age, the time after infection, and the severity of infection (β = -.132, p <.001; β = .098, p <.001; β = .075, p = .003). The mechanism of working memory impairment after infection was mainly focused on the aspects of neuroinflammation and the nerve invasiveness of the virus; at the same time, we also noticed some changes of the brain parenchymal structure.

CONCLUSION

COVID-19 can cause a decline in working memory ability, accompanied by neurological symptoms. However, there is a lack of studies to identify the structural and functional changes in specific brain regions that relate to the impaired working memory.

"Brain Fog" After COVID-19 Infection: How the Field of Neuropsychology Can Help Clear the Air

The chapter explores the role of neuropsychology in understanding brain fog as a subjective complaint in the context of COVID-19. It discusses the historical and medical significance of the term "brain fog" and its psychological and neurological aspects. The chapter identifies the cognitive domains commonly affected by brain fog, such as attention, executive function, memory, and language. Additionally, it emphasizes the impact of societal changes during the COVID-19 pandemic on the general population as a crucial backdrop for understanding the issue. The chapter also highlights the important role of clinical and research neuropsychologists in gaining clarity on grouped data and individual patients' cognitive and emotional difficulties after COVID-19 infection. It discusses indications for neuropsychological rehabilitation and therapy and describes typical therapy phases and methods, including new approaches like telemedicine, virtual reality, and mobile app-based rehabilitation and self-tracking. The chapter underscores that experiences of brain fog can vary among COVID-19 patients and may change over time. It provides clinicians and interested parties with an in-depth understanding of brain fog and its manifestations, concomitant subtypes, and concrete strategies for addressing it. The chapter emphasizes the critical role of neuropsychology in scientifically examining brain fog and advocating for personalized approaches to cognitive rehabilitation.

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

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

The effect of donepezil hydrochloride on post-COVID memory impairment: A randomized controlled trial

BACKGROUND

Post-Coronavirus Disease (COVID-19) condition, known as "post-COVID syndrome," is associated with a range of complications persisting even after recovery. Among these complications, cognitive dysfunction, including memory impairment, has been relatively common observed, impacting executive function and quality of life. To date, no approved treatment exists for this specific complication. Therefore, the present clinical trial aimed to investigate the impact of Donepezil Hydrochloride on post-COVID memory impairment.

METHODS

A randomized, controlled trial (Approval ID: IRCT20210816052203N1) was conducted, enrolling 25 patients with post-COVID memory impairment. Participants with a history of hospitalization were randomly assigned to either the drug group (n = 10) or the control group (n = 15). Memory indices were assessed at baseline, one month, and three months later using the Wechsler Memory Scale-Revised test. SPSS software and appropriate statistical tests were employed for data analysis.

RESULTS

The statistical analysis revealed no significant difference in WMS-R subtest and index scores between the drug and control groups at the 4-week and 12-week follow-up periods. However, within the drug group, there was a notable increase in the visual reproduction I and verbal paired associates II subtests during the specified time intervals.

CONCLUSION

While donepezil 5 mg did not exhibit a significant overall increase in memory scales compared to the control group over time, our findings suggest that this medication may exert a positive effect on specific memory subtests. Further research and exploration are warranted to better understand the potential benefits of donepezil in managing post-COVID-related memory impairment.

TRIAL REGISTRATION

The study was approved by the Research Ethics Committee of Aja University of Medical Sciences (Approval ID: IR.AJAUMS.REC.1400.125) and registered in the Iranian Registry of Clinical Trials (IRCT) (Approval ID: IRCT20210816052203N1).

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

Importance

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

Objective

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

Design, Setting, and Participants

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

Exposures

Hospitalization for COVID-19.

Main Outcomes and Measures

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

Results

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

Conclusions and Relevance

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

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.

Anxiety and depression played a central role in the COVID-19 mental distress: A network analysis

INTRODUCTION

Psychological, socio-demographics, and clinical factors play an important role in patients with COVID-19, but their relationship is complex. The network approach might be used to disentangle complex interactions in different systems. Using data from a multicentre, cross-sectional, survey among patients with COVID-19 in Spain (July-November 2020), we investigated the network structure of mental disorders symptoms, social support, and psychological resilience, and changes in network structures according to the presence of a pre-existing mental disorder or hospitalization for COVID-19.

METHODS

Subjects completed a survey to evaluate sociodemographic characteristics, COVID-19 infection status, resilience, social support, and symptoms of depression, anxiety disorders, post-traumatic stress disorder, panic attacks, and substance use disorder. 2084 patients with COVID-19 were included in the analysis. Network analysis was conducted to evaluate network and bridge centrality, and the network properties were compared between COVID-19 patients with and without a history of lifetime mental disorder, and between hospitalized and non-hospitalized patients.

LIMITATIONS

Generalization of our findings may be difficult since differences in network connectivity may exist in different populations or samples.

RESULTS

Anxiety and depression showed high centrality in patients with COVID-19 and anxiety showed the highest bridge influence in the network. Resilience and social support showed a low influence on mental disorder symptoms. Global network estimations show no statistically significant changes between patients with and without pre-existing mental disorders or between hospitalized and non-hospitalized patients.

CONCLUSIONS

Anxiety might be a key treatment target in patients with COVID-19 since its treatment might prevent other mental health adverse outcomes.

Post-Covid condition and clinic characteristics associated with SARS-CoV-2 infection: a 2-year follow-up to Brazilian cases

Until January 2023, Brazil recorded 37 million COVID-19 cases despite the decrease in mortality due to mass vaccination efforts against COVID-19. The infection continues to challenge researchers and health professionals with the persistent symptoms and onset manifestations after the acute phase of the disease, namely Post-Covid Condition (PCC). Being one of the countries with the highest infection rate, Brazil must prepare for a growing number of patients with chronic health consequences of COVID-19. Longitudinal studies that follow patients over extended periods are crucial in understanding the long-term impacts of COVID-19, including potential health consequences and the effects on quality of life. We describe the clinical profile of a cohort of COVID-19 patients infected during the first year of the pandemic in Brazil and a follow-up after two years to investigate the health impacts of SARS-CoV-2 infection. The first wave of SARS-CoV-2 infection in Brazil featured extensive drug misuse, notably the ineffective COVID kit comprised of ivermectin, antimalarials and azithromycin, and elevated in-hospital mortality. In the second phase of the study, Post-Covid Condition was reported by symptomatic COVID-19 subjects across different severity levels two years after infection. Long haulers are more likely to be women, previously hospitalized, and reported a range of symptoms from muscle pain to cognitive deficit. Our longitudinal study is essential to inform public health authorities to develop strategies and policies to control the spread of the virus and mitigate its impacts on society.

Neurological manifestations of post-acute sequelae of COVID-19: which liquid biomarker should we use?

Long COVID syndrome, also known as post-acute sequelae of COVID-19 (PASC), is characterized by persistent symptoms lasting 3-12 weeks post SARS-CoV-2 infection. Patients suffering from PASC can display a myriad of symptoms that greatly diminish quality of life, the most frequent being neuropsychiatric. Thus, there is an eminent need to diagnose and treat PASC related neuropsychiatric manifestation (neuro-PASC). Evidence suggests that liquid biomarkers could potentially be used in the diagnosis and monitoring of patients. Undoubtedly, such biomarkers would greatly benefit clinicians in the management of patients; however, it remains unclear if these can be reliably used in this context. In this mini review, we highlight promising liquid (blood and cerebrospinal fluid) biomarkers, namely, neuronal injury biomarkers NfL, GFAP, and tau proteins as well as neuroinflammatory biomarkers IL-6, IL-10, TNF-α, and CPR associated with neuro-PASC and discuss their limitations in clinical applicability.

Risk factors for post-COVID cognitive dysfunctions: the impact of psychosocial vulnerability

BACKGROUND

Cognitive dysfunction is a well-established manifestation of the post-COVID syndrome. Psychological vulnerability to stressors can modify disease trajectories, causing long-term risk for negative outcomes. Nonetheless, how premorbid risk factors and response to stressor affect neuropsychological changes is still incompletely understood. In this study, we explored the impact of psychosocial variables on cognitive functioning in a post-COVID sample.

METHODS

All subjects were submitted to a comprehensive neuropsychological battery and an assessment of perceived loneliness, post-traumatic stress, and changes in anxiety and depression levels. A social vulnerability index was also calculated. The set of psycho-social variables was reduced to two Principal Component Analysis (PCA) components: distress and isolation.

RESULTS

Forty-five percent of individuals showed cognitive impairments, with predominant memory and executive deficits. Post-traumatic stress disorder was clinically relevant in 44% of the sample. Social vulnerability scores of the sample were comparable to those of general population. The individual performance in learning and response initiation/suppression was directly related to distress component, encasing anxiety, stress, and depression measures.

CONCLUSION

These findings suggest that psychosocial assessment of post-COVID patients can detect fragile individuals at risk of cognitive impairments. Dedicated psychological support services may play a useful role in the prevention of post-COVID cognitive dysfunction.

Physical Function and Association with Cognitive Function in Patients in a Post-COVID-19 Clinic-A Cross-Sectional Study

Patients with long-term health sequelae of COVID-19 (post-COVID-19 condition) experience both physical and cognitive manifestations. However, there is still uncertainty about the prevalence of physical impairment in these patients and whether there is a link between physical and cognitive function. The aim was to assess the prevalence of physical impairment and investigate the association with cognition in patients assessed in a post-COVID-19 clinic. In this cross-sectional study, patients referred to an outpatient clinic ≥ 3 months after acute infection underwent screening of their physical and cognitive function as part of a comprehensive multidisciplinary assessment. Physical function was assessed with the 6-Minute Walk Test, the 30 s Sit-to-Stand Test and by measuring handgrip strength. Cognitive function was assessed with the Screen for Cognitive Impairment in Psychiatry and the Trail Making Test-Part B. Physical impairment was tested by comparing the patients' performance to normative and expected values. Association with cognition was investigated using correlation analyses and the possible explanatory variables regarding physical function were assessed using regression analyses. In total, we included 292 patients, the mean age was 52 (±15) years, 56% were women and 50% had been hospitalised during an acute COVID-19 infection. The prevalence of physical impairment ranged from 23% in functional exercise capacity to 59% in lower extremity muscle strength and function. There was no greater risk of physical impairment in previously hospitalised compared with the non-hospitalised patients. There was a weak to moderate association between physical and cognitive function. The cognitive test scores had statistically significant prediction value for all three outcomes of physical function. In conclusion, physical impairments were prevalent amongst patients assessed for post-COVID-19 condition regardless of their hospitalisation status and these were associated with more cognitive dysfunction.

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

BACKGROUND

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

METHODS

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

RESULTS

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

LIMITATIONS

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

CONCLUSIONS

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

The Clinical Observation of Inflammation Theory for Depression: The Initiative of the Formosa Long COVID Multicenter Study (FOCuS)

There is growing evidence that the coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is associated with increased risks of psychiatric sequelae. Depression, anxiety, cognitive impairments, sleep disturbance, and fatigue during and after the acute phase of COVID-19 are prevalent, long-lasting, and exerting negative consequences on well-being and imposing a huge burden on healthcare systems and society. This current review presented timely updates of clinical research findings, particularly focusing on the pathogenetic mechanisms underlying the neuropsychiatric sequelae, and identified potential key targets for developing effective treatment strategies for long COVID. In addition, we introduced the Formosa Long COVID Multicenter Study (FOCuS), which aims to apply the inflammation theory to the pathogenesis and the psychosocial and nutrition treatments of post-COVID depression and anxiety.

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

Background

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

Methods

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

Results

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

Conclusions

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

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Monitoring cognitive and psychological alterations in COVID-19 patients: A longitudinal neuropsychological study

BACKGROUND

SARS-COV-2 infection has been associated to long-lasting neuropsychiatric sequelae, including cognitive deficits, that persist after one year. However, longitudinal monitoring has been scarcely performed. Here, in a sample of COVID-19 patients, we monitor cognitive, psychological and quality of life-related profiles up to 22 months from resolution of respiratory disease.

METHODS

Out of 657 COVID-19 patients screened at Manzoni Hospital (Lecco, Italy), 22 underwent neuropsychological testing because of subjective cognitive disturbances at 6 months, 16 months, and 22 months. Tests of memory, attention, and executive functions were administered, along with questionnaires for depressive and Post-traumatic stress disorder (PTSD) symptoms, psychological well-being and quality of life. Cross-sectional descriptives, correlational, as well as longitudinal analyses considering COVID19-severity were carried out. A preliminary comparison with a sample of obstructive sleep apneas patients was also performed.

RESULTS

Around 50% of COVID-19 patients presented with cognitive deficits at t0. The most affected domain was verbal memory. Pathological scores diminished over time, but a high rate of borderline scores was still observable. Longitudinal analyses highlighted improvements in verbal and non-verbal long term memory, as well as attention, and executive functioning. Depression and PTSD-related symptoms were present in 30% of patients. The latter decreased over time and were associated to attentional-executive performance.

CONCLUSIONS

Cognitive dysfunctions in COVID-19 patients may extend over 1 year, yet showing a significant recovery in several cases. Cognitive alterations are accompanied by a significant psychological distress. Many patients displaying borderline scores, especially those at higher risk of dementia, deserve clinical monitoring.

Long COVID neuropsychological follow-up: Is cognitive rehabilitation relevant?

BACKGROUND

Duration of neuropsychological disorders caused by long COVID, and the variables that impact outcomes, are still largely unknown.

OBJECTIVE

To describe the cognitive profile of patients with long COVID post-participation in a neuropsychological rehabilitation program and subsequent reassessment and identify the factors that influence recovery.

METHODS

208 patients (mean age of 48.8 y.o.), mostly female, were reevaluated 25 months after their first COVID infection and 17 months after their initial evaluation. Patients underwent subjective assessment, Barrow Neurological Institute Screen for Higher Cerebral Functions (BNIS), Phonemic Verbal Fluency and Clock Drawing Tests (NEUPSILIN) for executive functions, Hospital Anxiety and Depression Scale (HADS) and WHOQol-Bref.

RESULTS

We noted a discrete improvement of neuropsychological symptoms 25 months after the acute stage of COVID-19; nonetheless, performance was not within the normative parameters of standardized neuropsychological testing. These results negatively impact QoL and corroborate patients' subjective assessments of cognitive issues experienced in daily life. Improvement was seen in those who participated in psychoeducational neuropsychological rehabilitation, had higher levels of education, and lower depression scores on the HADS.

CONCLUSION

Our data reveal the persistence of long-term cognitive and neuropsychiatric disorders in patients with long COVID. Neuropsychological rehabilitation is shown to be important, whether in-person or online.

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.

Glycyrrhizin and boswellic acids, the golden nutraceuticals: multitargeting for treatment of mild-moderate COVID-19 and prevention of post-COVID cognitive impairment

Breakthrough infections have been reported in fully vaccinated persons. Furthermore, rebound symptoms have been reported following the new FDA granted emergency use to combat SARS-CoV-2. Glycyrrhizin (GR) and boswellic acids (BAs) combination has been shown to have highly successful actions against COVID-19 in our recent clinical trial. However, the study is limited by the small sample size, and therefore, the aim of this article is to comprehensively evaluate recent evidence on the efficacy of GR and BAs in preventing the development of COVID-19 in patients with mild and moderate infections and in preventing post-COVID-19 cognitive impairment, which is the most important symptom after recovery from Covid-19 disease. We have reviewed and discussed information published since the outbreak of the COVID-19 pandemic until July 2022 on preclinical (in vivo, in vivo and bioinformatics) and clinical studies related to the antiviral, anti-inflammatory and immunomodulatory activity of Gr and BAs. Sixteen studies were performed to determine the efficacy of GR against SARS-CoV-2. Ten studies were used primarily for in vitro and in vivo assays and six used molecular docking studies. However, the antiviral activity of BAs against SARS-CoV-2 was determined in only five studies using molecular modeling and bioinformatics. All these studies confirmed that GR n and BAs have strong antiviral activity and can be used as a therapeutic agent for COVID-19 and as a protective agent against SARS-CoV-2. They may act by inhibiting the main protease SARS-CoV-2 (Mpro) responsible for replication and blocking spike protein-mediated cell entry. Only seven rigorously designed clinical trials regarding the usefulness of GR, BAs or their combinations in the treatment of COVID-19 have been published as of July 2022. Although there is no clinical study regarding the treatment of cognitive impairment after COVID-19 that has been published so far, several preclinical and clinical studies have demonstrated the potential effect of GR and BAs in the prevention and treatment of cognitive impairment by inhibiting the activity of several molecules that activate inflammatory signaling pathway. In conclusion, the findings of our study documented the beneficial use of GR and BAs to treat SARS-CoV-2 and its variants and prevent post-COVID cognitive impairment. However, it warrants further studies with a larger randomized sample size to ensure that the studies have sufficient evidence of benefits against COVID-19 and post-COVID-19 symptoms.

Comparison of Long COVID-19 Caused by Different SARS-CoV-2 Strains: A Systematic Review and Meta-Analysis

Although many studies of long COVID-19 were reported, there was a lack of systematic research which assessed the differences of long COVID-19 in regard to what unique SARS-CoV-2 strains caused it. As such, this systematic review and meta-analysis aims to evaluate the characteristics of long COVID-19 that is caused by different SARS-CoV-2 strains. We systematically searched the PubMed, EMBASE, and ScienceDirect databases in order to find cohort studies of long COVID-19 as defined by the WHO (Geneva, Switzerland). The main outcomes were in determining the percentages of long COVID-19 among patients who were infected with different SARS-CoV-2 strains. Further, this study was registered in PROSPERO (CRD42022339964). A total of 51 studies with 33,573 patients was included, of which three studies possessed the Alpha and Delta variants, and five studies possessed the Omicron variant. The highest pooled estimate of long COVID-19 was found in the CT abnormalities (60.5%; 95% CI: 40.4%, 80.6%) for the wild-type strain; fatigue (66.1%; 95% CI: 42.2%, 89.9%) for the Alpha variant; and ≥1 general symptoms (28.4%; 95% CI: 7.9%, 49.0%) for the Omicron variant. The pooled estimates of ≥1 general symptoms (65.8%; 95% CI: 47.7%, 83.9%) and fatigue were the highest symptoms found among patients infected with the Alpha variant, followed by the wild-type strain, and then the Omicron variant. The pooled estimate of myalgia was highest among patients infected with the Omicron variant (11.7%; 95%: 8.3%, 15.1%), compared with those infected with the wild-type strain (9.4%; 95%: 6.3%, 12.5%). The pooled estimate of sleep difficulty was lowest among the patients infected with the Delta variant (2.5%; 95%: 0.2%, 4.9%) when compared with those infected with the wild-type strain (24.5%; 95%: 17.5%, 31.5%) and the Omicron variant (18.7%; 95%: 1.0%, 36.5%). The findings of this study suggest that there is no significant difference between long COVID-19 that has been caused by different strains, except in certain general symptoms (i.e., in the Alpha or Omicron variant) and in sleep difficulty (i.e., the wild-type strain). In the context of the ongoing COVID-19 pandemic and its emerging variants, directing more attention to long COVID-19 that is caused by unique strains, as well as implementing targeted intervention measures to address it are vital.

Acute and long‑term psychiatric symptoms associated with COVID‑19 (Review)

Coronavirus disease 2019 (COVID-19) started spreading at the end of 2019 and despite the immediate actions of various governments with strict control, more and more individuals became infected daily. Due to the uncertainty and insecurity that still exists around this pandemic, there is an acute need for information and knowledge of what severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection entails. Respiratory and other physical symptoms received most of the medical attention, however, infected patients were also at risk for developing psychiatric and mental health disorders, such as depression, anxiety, and sleep disturbances. Available research reports a so-called 'post-COVID-19 syndrome', which refers to new and/or persistent signs and symptoms for over 12 weeks, following SARS. The aim of the present review was to provide a general overview of the psychiatric symptoms developed during SARS-CoV-2 infection and their long-term outcome, highlighting that, through follow-up with surviving patients it was revealed that some of the psychiatric symptoms of COVID-19 persisted for a long time after discharge and were also associated with negative effects on global functioning and lower quality of life.

Cognitive dysfunction associated with COVID-19: Prognostic role of circulating biomarkers and microRNAs

COVID-19 is renowned as a multi-organ disease having subacute and long-term effects with a broad spectrum of clinical manifestations. The evolving scientific and clinical evidence demonstrates that the frequency of cognitive impairment after COVID-19 is high and it is crucial to explore more clinical research and implement proper diagnostic and treatment strategies. Several central nervous system complications have been reported as comorbidities of COVID-19. The changes in cognitive function associated with neurodegenerative diseases develop slowly over time and are only diagnosed at an already advanced stage of molecular pathology. Hence, understanding the common links between COVID-19 and neurodegenerative diseases will broaden our knowledge and help in strategizing prognostic and therapeutic approaches. The present review focuses on the diverse neurodegenerative changes associated with COVID-19 and will highlight the importance of major circulating biomarkers and microRNAs (miRNAs) associated with the disease progression and severity. The literature analysis showed that major proteins associated with central nervous system function, such as Glial fibrillary acidic protein, neurofilament light chain, p-tau 181, Ubiquitin C-terminal hydrolase L1, S100 calcium-binding protein B, Neuron-specific enolase and various inflammatory cytokines, were significantly altered in COVID-19 patients. Furthermore, among various miRNAs that are having pivotal roles in various neurodegenerative diseases, miR-146a, miR-155, Let-7b, miR-31, miR-16 and miR-21 have shown significant dysregulation in COVID-19 patients. Thus the review consolidates the important findings from the numerous studies to unravel the underlying mechanism of neurological sequelae in COVID-19 and the possible association of circulatory biomarkers, which may serve as prognostic predictors and therapeutic targets in future research.

The Impact of Mild COVID-19 on Executive Functioning and Mental Health Outcomes in Young Adults

COVID-19 is associated with a range of long-lasting symptoms related to cognitive and psycho-emotional spheres. Even mild cases of the disease can lead to persistent cognitive deficits and deterioration of the psycho-emotional state. The purpose of our study was to examine the presence and frequency of psycho-emotional disorders and cognitive deficits in students who recovered from mild form of COVID-19. A total of 40 COVID-19 survivors and 25 healthy controls participated in our study. We assessed three core cognitive functions (inhibition, working memory, task-switching), reaction time and motor speed. We also assessed depression, anxiety and fatigue with self-report questionnaires. The COVID-19 group manifested increased depression and decreased inhibition in comparison with the controls. Our results show that even in young adults who have recovered from mild COVID-19, there are persisting cognitive and psycho-emotional deficits.