Brain fog as a Long-term Sequela of COVID-19

COVID-19 may Enduringly Impact Cognitive Performance and Brain Haemodynamics in Undergraduate Students

To date, 770 million people worldwide have contracted COVID-19, with many reporting long-term "brain fog". Concerningly, young adults are both overrepresented in COVID-19 infection rates and may be especially vulnerable to prolonged cognitive impairments following infection. This calls for focused research on this population to better understand the mechanisms underlying cognitive impairment post-COVID-19. Addressing gaps in the literature, the current study investigated differences in neuropsychological performance and cerebral haemodynamic activity following COVID-19 infection in undergraduate students. 94 undergraduates (age in years: M = 20.58, SD = 3.33, range = 18 to 46; 89 % female) at the University of Otago reported their COVID-19 infection history before completing a neuropsychological battery while wearing a multichannel near-infrared spectroscopy (NIRS) device to record prefrontal haemodynamics. We observed that 40 % retrospectively self-reported cognitive impairment (brain fog) due to COVID-19 and 37 % exhibited objective evidence of cognitive impairment (assessed via computerised testing), with some suggestion that executive functioning may have been particularly affected; however, group-level analyses indicated preserved cognitive performance post COVID-19, which may in part reflect varying compensatory abilities. The NIRS data revealed novel evidence that previously infected students exhibited distinct prefrontal haemodynamic patterns during cognitive engagement, reminiscent of those observed in adults four decades older, and this appeared to be especially true if they reported experiencing brain fog due to COVID-19. These results provide new insights into the potential neuropathogenic mechanisms influencing cognitive impairment following COVID-19.

Effect of a Nurse-Led Omaha System-Based Mobile Health Application in Managing Symptoms and Enhancing Quality of Life in Patients With a Communicable Disease: A Randomized Controlled Trial

This study investigated the effects of a nurse-led Omaha System-based mobile health application on physical, psychosocial, and cognitive symptoms and quality of life in patients with COVID-19 followed at home. This randomized control trial was conducted on 60 patients followed at home (30 in each intervention and control group). The intervention group received a nurse-led Omaha System-based mobile health application named COVOS, and the control group received usual care. Compared with the control group, the physical symptoms of the intervention group were significantly reduced at all follow-ups (first, second, and third months; P < .05). Psychosocial symptoms (depression, anxiety, stress) were significantly reduced, respectively, in the intervention group at all follow-ups: first and third months and second and third months ( P < .05). Cognitive symptoms were significantly reduced in the first month in the intervention group ( P = .014). Similarly, the physical component score of quality of life significantly improved in the first month, and the mental component score of quality of life significantly improved in the second and third months ( P < .05) in the intervention group. Results suggest that the COVOS had the potential to reduce effectively the physical, psychosocial, and cognitive symptoms of patients with COVID-19 and improve the quality of life of patients with COVID-19 followed at home.

Exploring the experiences of cognitive symptoms in Long COVID: a mixed-methods study in the UK

OBJECTIVE

To explore the lived experiences and extent of cognitive symptoms in Long COVID (LC) in a UK-based sample.

DESIGN

This study implemented a mixed-methods design. Eight focus groups were conducted to collect qualitative data, and the Framework Analysis was used to reveal the experiences and impact of cognitive symptoms. A self-report questionnaire was used to collect the quantitative data to assess the perceived change and extent of symptomology post COVID-19.

SETTING

Focus groups were conducted in April 2023 online via Zoom and in-person at the University of Leeds, UK.

PARTICIPANTS

25 people with LC living in the UK participated in the study. Participants were aged 19-76 years (M=43.6 years, SD=14.7) and included 17 women and 8 men.

RESULTS

Reduced cognitive ability was among the most prevalent symptoms reported by the study participants. Three key themes were identified from the qualitative data: (1) rich accounts of cognitive symptoms; (2) the impact on physical function and psychological well-being and (3) symptom management. Descriptions of cognitive symptoms included impairments in memory, attention, language, executive function and processing speed. Cognitive symptoms had a profound impact on physical functioning and psychological well-being, including reduced ability to work and complete activities of daily living. Strategies used for symptom management varied in effectiveness.

CONCLUSION

Cognitive dysfunction in LC appears to be exacerbated by vicious cycle of withdrawal from daily life including loss of employment, physical inactivity and social isolation driving low mood, anxiety and poor cognitive functioning. Previous evidence has revealed the anatomical and physiological biomarkers in the brain affecting cognition in LC. To synthesise these contributing factors, we propose the Long-COVID Interacting Network of factors affecting Cognitive Symptoms. This framework is designed to inform clinicians and researchers to take a comprehensive approach towards LC rehabilitation, targeting the neural, individual and lifestyle factors.

Cognitive function and brain structure in COVID-19 survivors: The role of persistent symptoms

Persistent COVID-19 symptoms post-acute state have been shown to have a significant negative impact on brain structure and function. In this study, we conducted magnetic resonance imaging (MRI) of the whole brain in 43 working-age adults (mean age: 44.79±10.80; range: 24-65 years) with a history of COVID-19 (731.17±312.41 days post-diagnosis), and also assessed their cognitive function (processing speed, attention, working memory, executive function, and recognition memory), mental health, and sleep quality. MRI data were processed using FSL to derive regional volumes for bilateral nucleus accumbens, caudate, pallidum, putamen, thalamus, amygdala, and hippocampus, and total grey matter, white matter, and cerebral spinal fluid volume, and analysed in relation to persistent COVID-19 symptom load, mental health, and sleep quality. Higher persistent COVID-19 symptom load was significantly associated with smaller putamen volume, lower response accuracy on working memory, executive function, and recognition memory tasks, as well as a longer time to complete the executive function task, and poorer mental health and sleep quality. Smaller putamen fully mediated the relationship between persistent COVID-19 symptom load and lower executive function. Further research is required to confirm whether reduced putamen volume and its association with poor executive function persists in COVID-19 survivors in the long term.

Depression, Anxiety, and Neuropsychiatric Symptom Burden in a Longitudinal Cohort with Persistent Psychophysical Post-COVID Olfactory Dysfunction

BACKGROUND/OBJECTIVES

Olfactory dysfunction (OD) is associated with a variety of neurologic deficits and impacts socialization decisions, mood, and overall quality of life. As a common symptom comprising the long COVID condition, persistent COVID-19-associated olfactory dysfunction (C19OD) may further impact the presentations of neuropsychiatric sequelae. Our study aims to characterize the longitudinal burden of depression, anxiety, and neuropsychiatric symptoms in a population with C19OD.

METHODS

Individuals with perceived C19OD completed a psychophysical screening evaluation of their sense of smell using the comprehensive Sniffin' Sticks olfactory assessment. Only those with validated psychophysical OD were included in this prospective longitudinal study for baseline and one-year follow-up. Participants also completed PHQ-9, Beck Anxiety Inventory (BAI), and neuropsychiatric symptom questionnaires at each time point. Anxiety, depression, and neuropsychiatric symptom prevalence was calculated and compared between time points with Pearson's chi-squared, Fisher's exact, and Wilcoxon rank sum tests.

RESULTS

Each neuropsychiatric symptom evaluated in this study was reported by 13-49% of longitudinal cohort participants at both baseline and follow-up, except for seizure (0% at baseline and follow-up) and word-finding difficulty (61-68% at baseline and follow-up). Word-finding and focus difficulties were the most commonly reported symptoms. In total, 41% of participants reported some level of depression at baseline and 38% of participants reported depression at one-year follow-up, while 29% and 27% of participants reported some level of anxiety at respective time points.

CONCLUSIONS

Individuals with C19OD are at risk for developing persistent neuropsychiatric conditions. These neurologic and psychiatric sequelae are persistent with repeated longitudinal assessment, even at nearly 2.5 years following initial COVID-19 diagnosis.

Neurological complications caused by SARS-CoV-2

SUMMARYSARS-CoV-2 can not only cause respiratory symptoms but also lead to neurological complications. Research has shown that more than 30% of SARS-CoV-2 patients present neurologic symptoms during COVID-19 (A. Pezzini and A. Padovani, Nat Rev Neurol 16:636-644, 2020, https://doi.org/10.1038/s41582-020-0398-3). Increasing evidence suggests that SARS-CoV-2 can invade both the central nervous system (CNS) (M.S. Xydakis, M.W. Albers, E.H. Holbrook, et al. Lancet Neurol 20: 753-761, 2021 https://doi.org/10.1016/S1474-4422(21)00182-4 ) and the peripheral nervous system (PNS) (M.N. Soares, M. Eggelbusch, E. Naddaf, et al. J Cachexia Sarcopenia Muscle 13:11-22, 2022, https://doi.org/10.1002/jcsm.12896), resulting in a variety of neurological disorders. This review summarized the CNS complications caused by SARS-CoV-2 infection, including encephalopathy, neurodegenerative diseases, and delirium. Additionally, some PNS disorders such as skeletal muscle damage and inflammation, anosmia, smell or taste impairment, myasthenia gravis, Guillain-Barré syndrome, ICU-acquired weakness, and post-acute sequelae of COVID-19 were described. Furthermore, the mechanisms underlying SARS-CoV-2-induced neurological disorders were also discussed, including entering the brain through retrograde neuronal or hematogenous routes, disrupting the normal function of the CNS through cytokine storms, inducing cerebral ischemia or hypoxia, thus leading to neurological complications. Moreover, an overview of long-COVID-19 symptoms is provided, along with some recommendations for care and therapeutic approaches of COVID-19 patients experiencing neurological complications.

Long-term COVID-19 sequelae by Theta and SARS-CoV-2 variants in a Philippine cohort

Introduction

Millions have been infected with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) since its emergence in 2019, but most patients make a full recovery. The long-term consequences of the infection are anticipated to unravel in the succeeding years with reports of patients experiencing chronic, debilitating sequelae post-infection commonly referred to as Long COVID. Various Variants of Concern (VoCs) have emerged as the SARS-CoV-2 virus evolved displaying increased infectivity and immune evasiveness. We investigate whether the infecting VoCs affect the sequelae of Long COVID in a Philippine cohort.

Methods

SARS-CoV-2 cases confirmed using RT-PCR followed by Next Generation Sequencing were identified from selected regions of the Philippines and recruited through a retrospective-prospective cohort design. Participants were divided based on the initial infecting VoC or Variant of Interest (VoI) and were subsequently interviewed regarding the presence, intensity, and frequency of key Long COVID symptoms, and followed up on two more separate sessions at least three (3) months apart for a total of three (3) data collection points (S1, S2, S3) to document changes in symptoms throughout the year-long study period.

Results

Long COVID symptoms were reported in 88, 82, and 68% of participants in S1, S2, and S3, respectively, showing declining incidence with elapsed time since the first reported infection. General symptoms including headache, fatigue, and post-exertional malaise were the most frequently reported symptoms, while neuropsychiatric symptoms were the second most frequently reported symptoms. In all three (3) sessions, intermittent brain fog, fatigue, and headache were the most frequently reported symptoms in all SARS-CoV-2 variant cohorts. Factors such as age, sex, comorbidities, and disease severity influenced symptom frequency, providing insight into the risk factors that contribute to the prevalence of this disease.

Conclusion

A large proportion (>68%) of cases in this Philippine cohort previously infected with different SARS-CoV-2 variants presented with long-term complications of COVID-19 characterized by a highly heterogeneous set of debilitating symptoms. The study highlights the need for long-term monitoring of Long COVID and its impact on human health and the need for our health systems to adopt policy response strategies.

Deep into Cognition: The Neuropsychological Identikit of Younger and Older Individuals after COVID-19 Infection

The literature on COVID-19 continues to increase daily. Cognitive sequelae associated with COVID-19 infection still draw the attention of the scientific community given the lack of consensus about their existence, etiology, characterization and reversibility. The aim of this study is to provide a neuropsychological identikit for younger (<65 years) and older (≥65 years) individuals diagnosed with COVID-19 infection, at baseline and after 3 and 6 months. In total, 226 individuals took part in a retrospective observational study and their cognitive performance was compared across groups (younger adults vs. older adults) and time (T0, T1, T2). The results highlighted differences between younger and older adults in the Montreal Cognitive Assessment (MoCA) global score, as expected in consideration of the different physiological conditions of the two populations. However, memory performance highlighted the two groups as characterized by a difference in patterns of recall that may move beyond a physiological explanation and provide information about COVID-19 cognitive sequelae. This study suggests that cognitive deficits observed in COVID-19 survivors may reflect a difficulty in attention and concentration that interferes mainly with retrieval processes. This result fits well with the concept of "brain fog" typical of post-COVID-19 syndrome and may also reflect the stress experienced while facing the pandemic.

Neurocognitive changes in a patient receiving esketamine for treatment-resistant depression

ABSTRACT

Esketamine, the s(+) enantiomer of ketamine, was approved in 2019 as the first rapid-acting intranasal spray medication for treatment-resistant depression; the drug is given in combination with an antidepressant. The treatment is self-administered in a clinical setting under the supervision of a healthcare provider and usually is well tolerated. Many of its adverse reactions are mild, temporary, and dose-dependent, and they improve with subsequent treatments. Although the prescribing information lists difficulty remembering or thinking as possible adverse reactions, a neurocognitive evaluation is not part of the initial patient evaluation. This case report focuses on a patient whose neurocognitive symptoms worsened with esketamine treatment, necessitating treatment discontinuation.

A Multidisciplinary Approach: Management and Rehabilitation of Children With Pediatric Post-COVID-19 Condition

Post-COVID-19 condition in children is a still largely unknown syndrome with a diverse pattern of symptoms, which can have a major impact on daily life. Currently, there are no evidence-based proven treatments, and the focus is on symptom management and recovery of daily functioning. A multidisciplinary, tailored approach is recommended, with attention to energy management and activity building, where the main goal should be a return to baseline levels of cognitive, physical and social activity.

Deterioration of neuroimmune homeostasis in Alzheimer's Disease patients who survive a COVID-19 infection

Growing evidence has implicated systemic infection as a significant risk factor for the development and advancement of Alzheimer's disease (AD). With the emergence of SARS-CoV-2 (COVID-19) and the resultant pandemic, many individuals from the same aging population vulnerable to AD suffered a severe systemic infection with potentially unidentified long-term consequences for survivors. To study the impact of COVID-19 survival on the brain's intrinsic immune system in a population also suffering from AD, we profiled post-mortem brain tissue from patients in the UF Neuromedicine Human Brain and Tissue Bank with a diagnosis of AD who survived a COVID-19 infection (COVID-AD) and contrasted our findings with AD patients who did not experience a COVID-19 infection, including a group of brain donors who passed away before arrival of SARS-CoV-2 in the United States. We assessed disease-relevant protein pathology and microglial and astrocytic markers by quantitative immunohistochemistry and supplemented these data with whole tissue gene expression analysis performed on the NanoString nCounter® platform. COVID-AD patients showed slightly elevated Aβ burden in the entorhinal, fusiform, and inferior temporal cortices compared to non-COVID-AD patients, while tau pathology burden did not differ between groups. Analysis of microglia revealed a significant loss of microglial homeostasis as well as exacerbated microgliosis in COVID-AD patients compared to non-COVID-AD patients in a brain region-dependent manner. Furthermore, COVID-AD patients showed reduced cortical astrocyte numbers, independent of functional subtype. Transcriptomic analysis supported these histological findings and, in addition, identified a dysregulation of oligodendrocyte and myelination pathways in the hippocampus of COVID-AD patients. In summary, our data demonstrate a profound impact of COVID-19 infection on neuroimmune and glial pathways in AD patients persisting for months post-infection, highlighting the importance of peripheral to central neuroimmune crosstalk in neurodegenerative diseases.

Long COVID Brain Fog Treatment: Findings from a Pilot Randomized Controlled Trial of Constraint-Induced Cognitive Therapy

Purpose

Long COVID brain fog is often disabling. Yet, no empirically-supported treatments exist. This study's objectives were to evaluate feasibility and efficacy, provisionally, of a new rehabilitation approach, Constraint-Induced Cognitive Therapy (CICT), for post-COVID-19 cognitive sequelae.

Design

Sixteen community-residents ≥ 3-months post-COVID-19 infection with mild cognitive impairment and dysfunction in instrumental activities of daily living (IADL) were enrolled. Participants were randomized to Immediate-CICT or treatment-as-usual (TAU) with crossover to CICT. CICT combined behavior change techniques modified from Constraint-Induced Movement Therapy with Speed of Processing Training, a computerized cognitive-training program. CICT was deemed feasible if (a) ≥80% of participants completed treatment, (b) the same found treatment highly satisfying and at most moderately difficult, and (c) <2 study-related, serious adverse-events occurred. The primary outcome was IADL performance in daily life (Canadian Occupational Performance Measure). Employment status and brain fog (Mental Clutter Scale) were also assessed.

Results

Fourteen completed Immediate-CICT (n=7) or TAU (n=7); two withdrew from TAU before their second testing session. Completers were [M (SD)]: 10 (7) months post-COVID; 51 (13) years old; 10 females, 4 males; 1 African American, 13 European American. All the feasibility benchmarks were met. Immediate-CICT, relative to TAU, produced very large improvements in IADL performance (M=3.7 points, p<.001, d=2.6) and brain fog (M=-4 points, p<.001, d=-2.9). Four of five non-retired Immediate-CICT participants returned-to-work post-treatment; no TAU participants did, p=.048.

Conclusions

CICT has promise for reducing brain fog, improving IADL, and promoting returning-to-work in adults with Long COVID. Findings warrant a large-scale RCT with an active-comparison group.

Prevalence and co-occurrence of cognitive impairment in children and young people up to 12-months post infection with SARS-CoV-2 (Omicron variant)

BACKGROUND

Cognitive impairment is often reported after SARS-CoV-2 infection, yet evidence gaps remain. We aimed to (i) report the prevalence and characteristics of children and young people (CYP) reporting "brain fog" (i.e., cognitive impairment) 12-months post PCR-proven SARS-CoV-2 infection and determine whether differences by infection status exist and (ii) explore the prevalence of CYP experiencing cognitive impairment over a 12-month period post-infection and investigate the relationship between cognitive impairment and poor mental health and well-being, mental fatigue and sleep problems.

METHODS

The Omicron CLoCk sub-study, set up in January 2022, collected data on first-time PCR-test-positive and PCR-proven reinfected CYP at time of testing and at 3-, 6- and 12-months post-testing. We describe the prevalence of cognitive impairment at 12-months, indicating when it was first reported. We characterise CYP experiencing cognitive impairment and use chi-squared tests to determine whether cognitive impairment prevalence varied by infection status. We explore the relationship between cognitive impairment and poor mental health and well-being, mental fatigue and trouble sleeping using validated scales. We examine associations at 3-, 6- and 12-months post-testing by infection status using Mann-Whitney U and chi-square tests.

RESULTS

At 12-months post-testing, 7.0 % (24/345) of first-positives and 7.5 % (27/360) of reinfected CYP experienced cognitive impairment with no difference between infection-status groups (p = 0.78). The majority of these CYP experienced cognitive impairment for the first time at either time of testing or 3-months post-test (no difference between the infection-status groups; p = 0.60). 70.8 % of first-positives experiencing cognitive impairment at 12-months, were 15-to-17-years-old as were 33.3 % of reinfected CYP experiencing cognitive impairment (p < 0.01). Consistently at all time points post-testing, CYP experiencing cognitive impairment were more likely to score higher on all Strengths and Difficulties Questionnaire subscales, higher on the Chalder Fatigue sub-scale for mental fatigue, lower on the Short Warwick-Edinburgh Mental Wellbeing Scale and report more trouble sleeping.

CONCLUSIONS

CYP have a fluctuating experience of cognitive impairment by 12-months post SARS-CoV-2-infection. Cognitive impairment is consistently correlated with poorer sleep, behavioural and emotional functioning over a 12-month period. Clinicians should be aware of cognitive impairment post-infection and its co-occurring nature with poorer sleep, behavioural and mental health symptoms.

Adaptation and Validation of the Turkish Version of the Brain Fog Scale

Brain fog is a condition that is characterized by poor concentration, memory loss, decreased cognitive function, and mental fatigue. Although it is generally known as a long-term COVID-19 symptom, brain fog has also been reported to be caused by many other diseases. Thus, it is necessary to assess this condition in certain populations. This study aimed to evaluate the reliability and validity of the Brain Fog Scale in a Turkish population. We conducted the study in two phases. In a pilot study including 125 participants, we confirmed the suitability of the scale for validity analyses and then conducted exploratory (n = 230) and confirmatory factor analyses (n = 343). The Cronbach's alpha value of the 23-item Brain Fog Scale was 0.966. In addition, the 23-item and three-factor structure was confirmed as a result of the analyses. These three factors are mental fatigue, impaired cognitive acuity, and confusion. We also found that participants previously diagnosed with COVID-19 had higher brain fog scores. This finding indicates that brain fog is an important condition that can accompany COVID-19. Furthermore, this validated construct has an acceptable fit and is a valid and useful tool for the Turkish population.

Long COVID management: a mini review of current recommendations and underutilized modalities

Long COVID is a condition that develops in a subset of patients after COVID-19 infection comprising of symptoms of varying severity encompassing multiple organ systems. Currently, long COVID is without consensus on a formal definition, identifiable biomarkers, and validated treatment. Long COVID is expected to be a long-term chronic condition for a subset of patients and is associated with suffering and incapacity. There is an urgent need for clear management guidelines for the primary care provider, who is essential in bridging the gap with more specialized care to improve quality of life and functionality in their patients living with long COVID. The purpose of this mini review is to provide primary care providers with the latest highlights from existing literature regarding the most common long COVID symptoms and current management recommendations. This review also highlights the underutilized interventions of stellate ganglion blocks and low-dose naltrexone, both with well-established safety profiles demonstrated to improve quality of life and functionality for patients suffering with some symptoms of long COVID, and encourages prompt referral to interventional pain management.

Exploring the Pathophysiology of Long COVID: The Central Role of Low-Grade Inflammation and Multisystem Involvement

Long COVID (LC), also referred to as Post COVID-19 Condition, Post-Acute Sequelae of SARS-CoV-2 Infection (PASC), and other terms, represents a complex multisystem disease persisting after the acute phase of COVID-19. Characterized by a myriad of symptoms across different organ systems, LC presents significant diagnostic and management challenges. Central to the disorder is the role of low-grade inflammation, a non-classical inflammatory response that contributes to the chronicity and diversity of symptoms observed. This review explores the pathophysiological underpinnings of LC, emphasizing the importance of low-grade inflammation as a core component. By delineating the pathogenetic relationships and clinical manifestations of LC, this article highlights the necessity for an integrated approach that employs both personalized medicine and standardized protocols aimed at mitigating long-term consequences. The insights gained not only enhance our understanding of LC but also inform the development of therapeutic strategies that could be applicable to other chronic conditions with similar pathophysiological features.

Subjective brain fog: a four-dimensional characterization in 25,796 participants

Importance

Brain fog is associated with significant morbidity and reduced productivity and gained increasing attention after COVID-19. However, this subjective state has not been systematically characterised.

Objective

To characterise self-reported brain fog.

Design

We systematically studied the cross-sectional associations between 29 a priori variables with the presence of "brain fog." The variables were grouped into four categories: demographics, symptoms and functional impairments, comorbidities and potential risk factors (including lifestyle factors), and cognitive score. Univariate methods determined the correlates of brain fog, with long-COVID and non-long-COVID subgroups. XGBoost machine learning model retrospectively characterised subjective brain fog. Bonferroni-corrected statistical significance was set at 5%.

Setting

Digital application for remote data collection.

Participants

25,796 individuals over the age of 18 who downloaded and completed the application.

Results

7,280 of 25,796 individuals (28.2%) reported experiencing brain fog, who were generally older (mean brain fog 35.7 ± 11.9 years vs. 32.8 ± 11.6 years, p < 0.0001) and more likely to be female (OR = 1.2, p < 0.001). Associated symptoms and functional impairments included difficulty focusing or concentrating (OR = 3.3), feeling irritable (OR = 1.6), difficulty relaxing (OR = 1.2, all p < 0.0001), difficulty following conversations (OR = 2.2), remembering appointments (OR = 1.9), completing paperwork and performing mental arithmetic (ORs = 1.8, all p < 0.0001). Comorbidities included long-COVID-19 (OR = 3.8, p < 0.0001), concussions (OR = 2.4, p < 0.0001), and higher migraine disability assessment scores (MIDAS) (+34.1%, all p < 0.0001). Cognitive scores were marginally lower with brain fog (-0.1 std., p < 0.001). XGBoost achieved a training accuracy of 85% with cross-validated accuracy of 74%, and the features most predictive of brain fog in the model were difficulty focusing and following conversations, long-COVID, and severity of migraines.

Conclusions and relevance

This is the largest study characterising subjective brain fog as an impairment of concentration associated with functional impairments in activities of daily living. Brain fog was particularly associated with a history of long-COVID-19, migraines, concussion, and with 0.1 standard deviations lower cognitive scores, especially on modified Stroop testing, suggesting impairments in the ability to inhibit cognitive interference. Further prospective studies in unselected brain fog sufferers should explore the full spectrum of brain fog symptoms to differentiate it from its associated conditions.

Evaluating qigong as integrative support for COVID-19 and Long-COVID-19 rehabilitation: a systematic review

Introduction

Amidst the ongoing global impact of COVID-19 on public health, there is an increasing focus on holistic strategies encompassing integrative therapies and rehabilitation techniques, particularly in addressing the challenges posed by Long-COVID-19. This review investigates the potential of Qigong, an ancient Chinese practice characterized by gentle movements, controlled breathing, and meditative elements, within the context of COVID-19.

Methods

A systematic search of PubMed, EMBASE, Web of Science, Scopus, and Google Scholar was conducted to identify pertinent clinical studies.

Results

Following thorough database scrutiny, nine studies were identified as meeting the eligibility criteria. Across the spectrum of COVID-19 severity, individuals engaging in qigong practice exhibited notable enhancements in both physical and psychological wellbeing, evidenced by ameliorated respiratory symptoms, reduced anxiety levels, enhanced sleep quality, bolstered mental wellbeing, and augmented health-related quality of life. Moreover, qigong training, whether employed independently or in conjunction with other therapies, demonstrated beneficial effects on Long-COVID-19 symptoms, encompassing persistent respiratory issues, dizziness, sleep disturbances, and compromised health-related quality of life.

Discussion

This review underscores the necessity for further investigation to quantify and standardize the contribution of Qigong to COVID-19 recovery and rehabilitation. Such endeavors aim to integrate this accessible and low-impact practice into public health strategies and comprehensive treatment regimens.

Systematic review registration

The review protocol was registered in the Open Science Framework under the following doi: 10.17605/OSF.IO/7K5X6 (URL: https://osf.io/7k5x6).

Post-COVID-19 cognitive symptoms in patients assisted by a teleassistance service: a retrospective cohort study

Introduction

Four years after the onset of the COVID-19 pandemic, the frequency of long-term post-COVID-19 cognitive symptoms is a matter of concern given the impact it may have on the work and quality of life of affected people.

Objective

To evaluate the incidence of post-acute COVID-19 cognitive symptoms, as well as the associated risk factors.

Methods

Retrospective cohort, including outpatients with laboratory-confirmed COVID-19 and who were assisted by a public telehealth service provided by the Telehealth Network of Minas Gerais (TNMG), during the acute phase of the disease, between December/2020 and March/2022. Data were collected through a structured questionnaire, applied via phone calls, regarding the persistence of COVID-19 symptoms after 12 weeks of the disease. Cognitive symptoms were defined as any of the following: memory loss, problems concentrating, word finding difficulties, and difficulty thinking clearly.

Results

From 630 patients who responded to the questionnaire, 23.7% presented cognitive symptoms at 12 weeks after infection. These patients had a higher median age (33 [IQR 25-46] vs. 30 [IQR 24-42] years-old, p = 0.042) with a higher prevalence in the female sex (80.5% vs. 62.2%, p < 0.001) when compared to those who did not present cognitive symptoms, as well as a lower prevalence of smoking (8.7% vs. 16.2%, p = 0.024). Furthermore, patients with persistent cognitive symptoms were more likely to have been infected during the second wave of COVID-19 rather than the third (31.0% vs. 21.3%, p = 0.014). Patients who needed to seek in-person care during the acute phase of the disease were more likely to report post-acute cognitive symptoms (21.5% vs. 9.3%, p < 0,001). In multivariate logistic regression analysis, cognitive symptoms were associated with female sex (OR 2.24, CI 95% 1.41-3.57), fatigue (OR 2.33, CI 95% 1.19-4.56), depression (OR 5.37, CI 95% 2.19-13.15) and the need for seek in-person care during acute COVID-19 (OR 2.23, CI 95% 1.30-3.81).

Conclusion

In this retrospective cohort of patients with mostly mild COVID-19, cognitive symptoms were present in 23.7% of patients with COVID-19 at 12 weeks after infection. Female sex, fatigue, depression and the need to seek in-person care during acute COVID-19 were the risk factors independently associated with this condition.

The bidirectional links between coronavirus disease 2019 and Alzheimer's disease

Coronavirus disease 2019 (COVID-19) can be a critical disease, particularly in the elderly and those with comorbidities. Patients with Alzheimer's disease are more vulnerable to COVID-19 consequences. The latest results have indicated some common risk factors for both diseases. An understanding of the pathological link between COVID-19 and Alzheimer's disease will help develop timely strategies to treat both diseases. This review explores the bidirectional links between COVID-19 and Alzheimer's disease.

A Three-Year Cross-Sectional Analysis of Depression, Anxiety, and Quality of Life in Patients with Post-COVID-19 Syndrome

Background

This study explores the longitudinal psychosocial impact of Long-COVID syndrome, also known as Post-COVID-19 syndrome, characterized by enduring symptoms after coronavirus disease (COVID-19) infection, over the years 2020, 2021, and 2022. It aimed to examine the variations in depression, anxiety, and quality of life among Post-COVID-19 patients during these years, hypothesizing significant inter-year differences reflecting the pandemic's evolving influence.

Methods

Conducted at Victor Babes Hospital for Infectious Diseases and Pulmonology, Romania, this cross-sectional research involved 324 patients diagnosed with mild to moderate COVID-19, assessed six months post-hospitalization. Standardized instruments, namely Short Form (SF-36) for quality of life, Generalised Anxiety Disorder Assessment (GAD-7) for anxiety, and Patient Health Questionnaire (PHQ-9) for depression, were utilized.

Results

The study observed a consistent average patient age of around 55 years across the years. A notable increase in COVID-19 vaccination rates was recorded, rising from 20.9% in 2020 to over 70% in 2022 (p<0.001). Trends in key post-COVID symptoms like fatigue and cognitive issues varied over the years. Importantly, there was a consistent decrease in feelings of sadness or depression, with scores declining from 7.3 in 2020 to 4.8 in 2022 (p<0.001). The SF-36 survey indicated a steady improvement in overall health, reaching 55.8±7.1 in 2022 (p=0.035). Both GAD-7 and PHQ-9 scores showed significant reductions in anxiety and depression over the years, with p-values of 0.030 and 0.031, respectively. Factors such as smoking status, substance use, and the initial severity of COVID-19 infection were significantly associated with depression levels.

Conclusion

The findings suggest that despite persistent physical symptoms, Long-COVID patients experienced enhancements in mental well-being and quality of life over the studied period. The increasing vaccination rates might have contributed to this improvement. Addressing modifiable risk factors like smoking and substance use could further optimize post-COVID care and mental health outcomes.

Advanced magnetic resonance neuroimaging techniques: feasibility and applications in long or post-COVID-19 syndrome - a review

Long-term or post-COVID-19 syndrome (PCS) is a condition that affects people infected with SARS‑CoV‑2, the virus that causes COVID-19. PCS is characterized by a wide range of persistent or new symptoms that last months after the initial infection, such as fatigue, shortness of breath, cognitive dysfunction, and pain. Advanced magnetic resonance (MR) neuroimaging techniques can provide valuable information on the structural and functional changes in the brain associated with PCS as well as potential biomarkers for diagnosis and prognosis. In this review, we discuss the feasibility and applications of various advanced MR neuroimaging techniques in PCS, including perfusion-weighted imaging (PWI), diffusion-weighted imaging (DWI), susceptibility-weighted imaging (SWI), functional MR imaging (fMRI), diffusion tensor imaging (DTI), and tractography. We summarize the current evidence on neuroimaging findings in PCS, the challenges and limitations of these techniques, and the future directions for research and clinical practice. Although still uncertain, advanced MRI techniques show promise for gaining insight into the pathophysiology and guiding the management of COVID-19 syndrome, pending larger validation studies.

Cortical GABA Levels Are Reduced in Post-Acute COVID-19 Syndrome

After recovering from the acute COVID-19 illness, a substantial proportion of people continue experiencing post-acute sequelae of COVID-19 (PASC), also termed "long COVID". Their quality of life is adversely impacted by persistent cognitive dysfunction and affective distress, but the underlying neural mechanisms are poorly understood. The present study recruited a group of mostly young, previously healthy adults (24.4 ± 5.2 years of age) who experienced PASC for almost 6 months following a mild acute COVID-19 illness. Confirming prior evidence, they reported noticeable memory and attention deficits, brain fog, depression/anxiety, fatigue, and other symptoms potentially suggestive of excitation/inhibition imbalance. Proton magnetic resonance spectroscopy (1H-MRS) was used to examine the neurochemical aspects of cell signaling with an emphasis on GABA levels in the occipital cortex. The PASC participants were compared to a control (CNT) group matched in demographics, intelligence, and an array of other variables. Controlling for tissue composition, biological sex, and alcohol intake, the PASC group had lower GABA+/water than CNT, which correlated with depression and poor sleep quality. The mediation analysis revealed that the impact of PASC on depression was partly mediated by lower GABA+/water, indicative of cortical hyperexcitability as an underlying mechanism. In addition, N-acetylaspartate (NAA) tended to be lower in the PASC group, possibly suggesting compromised neuronal integrity. Persistent neuroinflammation may contribute to the pathogenesis of PASC-related neurocognitive dysfunction.

Metabolic and toxicological considerations regarding CGRP mAbs and CGRP antagonists to treat migraine in COVID-19 patients: a narrative review

INTRODUCTION

Migraine pharmacological therapies targeting calcitonin gene-related peptide (CGRP), including monoclonal antibodies and gepants, have shown clinical effect and optimal tolerability. Interactions between treatments of COVID-19 and CGRP-related drugs have not been reviewed.

AREAS COVERED

An overview of CGRP, a description of the characteristics of each CGRP-related drug and its response predictors, COVID-19 and its treatment, the interactions between CGRP-related drugs and COVID-19 treatment, COVID-19 and vaccination-induced headache, and the neurological consequences of Covid-19.

EXPERT OPINION

Clinicians should be careful about using gepants for COVID-19 patients, due to the potential drug interactions with drugs metabolized via CYP3A4 cytochrome. In particular, COVID-19 treatment (especially nirmatrelvir packaged with ritonavir, as Paxlovid) should be considered cautiously. It is advisable to stop or adjust the dose (10 mg atogepant when used for episodic migraine) of gepants when using Paxlovid (except for zavegepant). CGRP moncolconal antibodies (CGRP-mAbs) do not have drug - drug interactions, but a few days' interval between a COVID-19 vaccination and the use of CGRP mAbs is recommended to allow the accurate identification of the possible adverse effects, such as injection site reaction. Covid-19- and vaccination-related headache are known to occur. Whether CGRP-related drugs would be of benefit in these circumstances is not yet known.

Epidemiology of neurocognitive disorders in adults from urban-marginalized areas: a door-to-door population-based study in Puente Piedra, Lima, Peru

Background

In Latin America (LA), the prevalence of dementia is expected to triple to 150 million people by 2050. The 2020 Lancet Commission report identified several modifiable dementia risk factors, yet few social and environmental factors, most relevant to vulnerable regions of LA, were highlighted in this report. We sought to assess the epidemiology of neurocognitive disorders (NCD) in Puente Piedra, one of the most socially and economically vulnerable districts of Lima, the capital of Peru.

Methodology

This was a cross-sectional door-to-door observational study that used two-stage household sampling. One young adult (30-59 years) and one older adult (>60 years) per household were enrolled. We collected demographic, clinical, and neurocognitive data. Addenbrooke's Cognitive Examination (young adults) and the RUDAS-PE (older adults) were used, classifying participants as cognitively normal, possible mild NCD, or possible major NCD.

Results

We enrolled 247 participants (median age 46 years; 67% female). One-fourth had not completed secondary school and more than 50% completed only secondary school. Most participants were housewives (46%) and 21% did not have health insurance. The overall prevalence of possible NCD was 30% (25.6 and 41.8% among younger adults and older adults, respectively). Among younger adults, those ages 55-59 years more frequently had NCD (70%) compared to younger age ranges. Among older adults, only 3 subjects (4.5%) had major NCD.

Conclusion

We found a high frequency of possible NCDs in a socially and economically vulnerable community in Lima, Peru, with younger adults showing levels of NCD higher than expected. Our findings support the need for health systems to incorporate cognitive screenings programs for NCD in younger ages. Future research on NCD would include younger populations, particularly in vulnerable communities.

The functional and structural changes in the hippocampus of COVID-19 patients

Since the hippocampus is predominantly susceptible to injuries caused by COVID-19, there are increasing data indicating the likelihood of post-infection memory loss and quickening neurodegenerative disorders, such as Alzheimer's disease. This is due to the fact that the hippocampus has imperative functions in spatial and episodic memory as well as learning. COVID-19 activates microglia in the hippocampus and induces a CNS cytokine storm, leading to loss of hippocampal neurogenesis. The functional and structural changes in the hippocampus of COVID-19 patients can explain neuronal degeneration and reduced neurogenesis in the human hippocampus. This will open a window to explain memory and cognitive dysfunctions in "long COVID" through the resultant loss of hippocampal neurogenesis.

COVID-19 annual update: a narrative review

Three and a half years after the pandemic outbreak, now that WHO has formally declared that the emergency is over, COVID-19 is still a significant global issue. Here, we focus on recent developments in genetic and genomic research on COVID-19, and we give an outlook on state-of-the-art therapeutical approaches, as the pandemic is gradually transitioning to an endemic situation. The sequencing and characterization of rare alleles in different populations has made it possible to identify numerous genes that affect either susceptibility to COVID-19 or the severity of the disease. These findings provide a beginning to new avenues and pan-ethnic therapeutic approaches, as well as to potential genetic screening protocols. The causative virus, SARS-CoV-2, is still in the spotlight, but novel threatening virus could appear anywhere at any time. Therefore, continued vigilance and further research is warranted. We also note emphatically that to prevent future pandemics and other world-wide health crises, it is imperative to capitalize on what we have learnt from COVID-19: specifically, regarding its origins, the world's response, and insufficient preparedness. This requires unprecedented international collaboration and timely data sharing for the coordination of effective response and the rapid implementation of containment measures.

A likely association between low mannan-binding lectin level and brain fog onset in long COVID patients

Brain fog can be described as a constellation of new-onset neuropsychiatric sequelae in the post-acute phase of COVID-19 (long COVID). The symptoms include inattention, short-term memory loss, and reduced mental acuity, which may undermine cognition, concentration, and sleep. This cognitive impairment, persisting for weeks or months after the acute phase of SARS-CoV-2 infection, can significantly impact on daily activities and the quality of life. An important role for the complement system (C) in the pathogenesis of COVID-19 has emerged since the beginning of pandemic outbreak. A number of pathophysiological characteristics including microangiopathy and myocarditis have been attributed to dysregulated C activation due to SARS-CoV-2 infection. Mannan-binding lectin (MBL), the first recognition subcomponent of the C lectin pathway, has been shown to bind to glycosylated SARS-CoV-2 spike protein, genetic variants of MBL2 are suggested to have an association with severe COVID-19 manifestations requiring hospitalization. In the present study, we evaluated MBL activity (lectin pathway activation) and levels in the sera of a cohort of COVID-19 patients, presenting brain fog or only hyposmia/hypogeusia as persistent symptoms, and compared them with healthy volunteers. We found significantly lower levels of MBL and lectin pathway activity in the sera of patients experiencing brain fog as compared to recovered COVID-19 patients without brain fog. Our data indicate that long COVID-associated brain fog can be listed among the variegate manifestations of increased susceptibility to infections and diseases contributed by MBL deficiency.

Depression and brain fog as long-COVID mental health consequences: Difficult, complex and partially successful treatment of a 72-year-old patient-A case report

SARS-CoV-2 (COVID-19) infection can result in long-term health consequences i.e., long COVID. The clinical manifestations of long COVID include depression, anxiety, brain fog with cognitive dysfunction, memory issues, and fatigue. These delayed effects of COVID-19 occur in up to 30% of people who have had an acute case of COVID-19. In this case report, a 72-year-old, fully vaccinated patient without pre-existing somatic or mental illnesses, or other relevant risk factors was diagnosed with long COVID. Nine months following an acute COVID-19 infection, the patient's depressive symptoms improved, but memory and concentration difficulties persisted, and the patient remains unable to resume work. These long-term symptoms are possibly linked to micro-hemorrhages detected during examinations of the patient's brain following COVID-19 infection. Patient treatment was complex, and positive results were attained via antidepressants and non-drug therapies e.g., art, music, drama, dance and movement therapy, physiotherapy, occupational therapy, and psychotherapy.