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

Multifactorial Memory Questionnaire: a comparison of young and older adults

The Multifactorial Memory Questionnaire (MMQ; Troyer & Rich, [2002]. Psychometric properties of a new metamemory questionnaire for older adults. The Journals of Gerontology Series B: Psychological Sciences and Social Sciences, 57(1), P19-P27) is a widely used measure of subjective memory consisting of three scales: Satisfaction, Ability, and Strategies. Although subjective memory complaints are prevalent across different age groups, the factor structure and psychometric properties of the MMQ have yet to be examined in young adults. Here, we independently replicated the original MMQ factor structure in N = 408 young adults (YA) recruited from undergraduate courses and N = 327 older adults (OA) and, for the first time, assessed the age-invariance of the scale using measurement invariance testing. YAs made significantly higher ratings than OAs on MMQ-Satisfaction and MMQ-Strategies, indicating greater satisfaction with their memory and greater use of strategies, but the groups were similar on MMQ-Ability. The original MMQ factor structure was replicated in OAs but not in YAs, and age invariance was not supported. Future studies seeking to compare young and older adults could therefore consider either requesting modification of the MMQ for use with young adults or using a different scale.

Development of a self-administered online battery for remote assessment of executive functions and verbal memory: equivalence with face-to-face administration, preliminary norms, and acceptance

OBJECTIVES

Interest in teleneuropsychology services increased considerably after the COVID-19 pandemic. However, the utility of unsupervised administration of computerized tests remains largely unexplored. In the present study, we developed a brief computerized battery that assesses self-reported cognitive abilities and performances on executive functioning and verbal memory. We investigated the equivalence of the self-administration online (SAO) procedure and the face-to-face (FTF) administration. Preliminary normative data were developed and the acceptance of the SAO procedure was explored.

METHODS

A community sample of 169 Greek adults [94 women; mean age: 41.95 (SD = 13.40) years, mean years of education: 15.10 (SD = 2.65)] completed the SAO assessment. A subgroup of 40 participants was tested in a counterbalanced way both with SAO and FTF. Participants' performances were compared with paired sample t-tests and the agreement between the two methods was estimated with intraclass correlation coefficients (ICCs). Multiple linear regression analyses were applied to investigate the effect of demographic characteristics on SAO measures.

RESULTS

No difference between SAO and FTF scores was observed. ICCs indicated moderate to good agreement (.418-.848) for most measures. Age was positively associated with self-reported cognitive state and negatively with neuropsychological performances and the level of acceptance of the SAO procedure. Approximately 80% of participants reported satisfaction from the SAO assessment, 69% good compliance with the instructions, but less than 30% belief that the FTF assessment could be adequately replaced.

CONCLUSION

SAO testing is feasible and well accepted among Greek adults yielding equivalent results with FTF testing. Despite the wide satisfaction, though, notable reluctance was noted for the substitution of FTF with SAO procedures.

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.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

TRIAL REGISTRATION

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

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

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

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

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

Capturing postpandemic changes in research participants

The impact of the COVID-19 pandemic on physical and mental health hardly need be reiterated. Yet, there are likely other indirect aftereffects of COVID-19 infection in addition to the direct effects. This article aims to initiate a conversation regarding difficult-to-capture outcomes of the pandemic that are relevant to researchers who test human participants. These considerations encourage collection of additional measures when assessing pre- versus postpandemic patterns of behavior.

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

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

Guiding future research on psychological interventions in people with COVID-19 and post COVID syndrome and comorbid emotional disorders based on a systematic review

Objective

The COVID-19 pandemic has been emotionally challenging for the entire population and especially for people who contracted the illness. This systematic review summarizes psychological interventions implemented in COVID-19 and long COVID-19 patients who presented comorbid emotional disorders.

Methods and measures

3,839 articles were identified in 6 databases and 43 of them were included in this work. Two independent researchers selected the articles and assessed their quality.

Results

2,359 adults were included in this review. Severity of COVID-19 symptoms ranged from asymptomatic to hospitalized patients; only 3 studies included long COVID-19 populations. Similar number of randomized controlled studies (n = 15) and case studies (n = 14) were found. Emotional disorders were anxiety and/or depressive symptoms (n = 39) and the psychological intervention most represented had a cognitive behavioral approach (n = 10). Length of psychological programs ranged from 1-5 sessions (n = 6) to 16 appointments (n = 2). Some programs were distributed on a daily (n = 4) or weekly basis (n = 2), but other proposed several sessions a week (n = 4). Short (5-10 min, n = 4) and long sessions (60-90 min, n = 3) are proposed. Most interventions were supported by the use of technologies (n = 18). Important risk of bias was present in several studies.

Conclusion

Promising results in the reduction of depressive, anxiety and related disorders have been found. However, important limitations in current psychological interventions were detected (i.e., duration, format, length, and efficacy of interventions were not consistently established across investigations). The results derived from our work may help to understand clinical practices in the context of pandemics and could guide future efforts to manage emotional suffering in COVID-19 patients. A stepped model of care could help to determine the dosage, length and format of delivery for each patient.Systematic review registration: PROSPERO 2022 CRD42022367227. Available from: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022367227.

Cognitive Dysfunction in Hospitalized Patient with Moderate-to-Severe COVID-19: A 1-Year Prospective Observational Study

Purpose

To screen the neurocognitive impairment persistent post-COVID-19.

Patients and Methods

We assessed the neuropsychiatric disorders associated with COVID-19 in a prospective study, by "Mini-Mental State Examination" (MMSE) and Montreal Cognitive Assessment (MoCA) questionnaires, applied in the discharge to COVID-19 hospitalized patients for moderate and severe forms of disease. They were followed-up in 6 and 12 months.

Results

The tests were performed in the baseline and were reevaluated after 6 and 12 months. Baseline cognitive dysfunction was found in 12.4% of patients, according to the MMSE test and in 19.7% by the MoCA scores. Overall cognitive dysfunction in COVID-19 was returned to normal after 6 months, although some tasks are more severe and persistently impaired, such as attention, concentration, short memory, and execution skills. The male gender and the degree of hypoxia, related to the severity of COVID-19 infection, were related to cognitive dysfunction in the study group.

Conclusion

Cognitive domain impairments related to COVID-19 could persist over 6 months post-acute infectious episode requiring systematic screening for early diagnosis of progressive brain pathologies and rehabilitation.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

[Dementia Screening and Test Psychology in German General and Specialist Practices under Conditions of the Corona Pandemic]

OBJECTIVE

To analyse changes in frequencies of test psychology examinations (TPE) relevant to detect change in dementia diagnosis in general (GP) and neuropsychiatric (NP) practices during the Covid 19 pandemic.

METHODS

Cross-sectional study analysis comparing the number of patients aged ≥ 70 with at least one TPE in 908 GP and 107 NP-practices in 2018-2019 (prepandemic) and 2020-2021 (pandemic) using descriptive statisics and correlations.

RESULTS

While there was a large decrease in TPE between 2018-2019 and 2020-2021 (- 18.4%) conducted in NP-practices, it remained stable in GP-practices (+ 2.6%). In both GP and NP, there was a strong correlation between the number of patients tested and newly diagnosed with dementia.

CONCLUSION

TPE in performing in GP practices appears less susceptible to a pandemic-related decline in the provision compared to NP practices. Further research is needed to reveal the reasons for these differences.

Cognitive Aspects of COVID-19

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

Long-term health consequences among individuals with SARS-CoV-2 infection compared to individuals without infection: results of the population-based cohort study CoMoLo Follow-up

BACKGROUND

Most of the previous studies on health sequelae of COVID-19 are uncontrolled cohorts and include a relatively short follow-up. This population-based multi-center cohort study examined health consequences among individuals about 1 to 1.5 years after SARS-CoV-2 infection compared with non-infected.

METHODS

The study population consisted of adults (≥ 18 years) from four municipalities particularly affected by the COVID-19 pandemic in the year 2020 who completed a detailed follow-up questionnaire on health-related topics. Exposure was the SARS-CoV-2 infection status (based on IgG antibodies, PCR test, or physician-diagnosis of COVID-19) at baseline (May to December 2020). Outcomes assessed at follow-up (October 2021 to January 2022; mean: 452 days) included recurrent or persistent health complaints, incident diseases, health-related quality of life (PROMIS-29), subjective health, and subjective memory impairment. Logistic and linear regression models were adjusted for baseline sociodemographic and lifestyle characteristics (age, sex, municipality, education, smoking, body mass index), pre-existing health conditions (chronic disease/health problem, health-related activity limitation, depressive/anxiety disorder), and follow-up time.

RESULTS

Among 4817 participants, 350 had a SARS-CoV-2 infection at baseline and 4467 had no infection at baseline or during follow-up. Those with an infection statistically significantly more often reported 7 out of 18 recurrent or persistent health complaints at follow-up: smell/taste disorders (12.8% vs. 3.4%, OR 4.11), shortness of breath (23.0% vs. 9.5%, 3.46), pain when breathing (4.7% vs. 1.9%, 2.36), fatigue (36.9% vs. 26.1%, 1.76), weakness in legs (12.8% vs. 7.8%, 1.93), myalgia/joint pain (21.9% vs. 15.1%, 1.53) and cough (30.8% vs. 24.8%, 1.34) and 3 out of 6 groups of incident diseases: liver/kidney (2.7% vs. 0.9%, 3.70), lung (3.2% vs. 1.1%, 3.50) and cardiovascular/metabolic (6.5% vs. 4.0%, 1.68) diseases. Those with an infection were significantly more likely to report poor subjective health (19.3% vs. 13.0%, 1.91), memory impairment (25.7% vs. 14.3%, 2.27), and worse mean scores on fatigue and physical function domains of PROMIS-29 than non-infected.

CONCLUSION

Even after more than one year, individuals with SARS-CoV-2 infection showed an increased risk of various health complaints, functional limitations, and worse subjective well-being, pointing toward profound health consequences of SARS-CoV-2 infection relevant for public health.

Covid-19 related cognitive, structural and functional brain changes among Italian adolescents and young adults: a multimodal longitudinal case-control study

Coronavirus disease 2019 (COVID-19) has been associated with brain functional, structural, and cognitive changes that persist months after infection. Most studies of the neurologic outcomes related to COVID-19 focus on severe infection and aging populations. Here, we investigated the neural activities underlying COVID-19 related outcomes in a case-control study of mildly infected youth enrolled in a longitudinal study in Lombardy, Italy, a global hotspot of COVID-19. All participants (13 cases, 27 controls, mean age 24 years) completed resting state functional (fMRI), structural MRI, cognitive assessments (CANTAB spatial working memory) at baseline (pre-COVID) and follow-up (post-COVID). Using graph theory eigenvector centrality (EC) and data-driven statistical methods, we examined differences in ECdelta (i.e., the difference in EC values pre- and post-COVID-19) and volumetricdelta (i.e., the difference in cortical volume of cortical and subcortical areas pre- and post-COVID) between COVID-19 cases and controls. We found that ECdeltasignificantly between COVID-19 and healthy participants in five brain regions; right intracalcarine cortex, right lingual gyrus, left hippocampus, left amygdala, left frontal orbital cortex. The left hippocampus showed a significant decrease in volumetricdelta between groups (p=0.041). The reduced ECdelta in the right amygdala associated with COVID-19 status mediated the association between COVID-19 and disrupted spatial working memory. Our results show persistent structural, functional and cognitive brain changes in key brain areas associated with olfaction and cognition. These results may guide treatment efforts to assess the longevity, reversibility and impact of the observed brain and cognitive changes following COVID-19.

Systematic Review and Meta-Analysis of Clinically Relevant Executive Functions Tests Performance after COVID-19

It is widely known that COVID-19 has a number of prolonged effects on general health, wellbeing, and cognitive functioning. However, studies using differentiated performance measures of cognitive functions are still not widely spread making it hard to assess the exact functions that get impaired. Taking into account the similarities between post-COVID 'brain fog' and chemofog, we hypothesized that executive functions (EF) would be impaired. Literature search yielded six studies with 14 effect sizes of interest; pooled effect size was small to medium (d = -0.35). Combined with a narrative synthesis of six studies without a comparison group, these results show that EF get impaired after COVID-19; although, in most cases the impairment is transient and does not seem to be severe. These results specify the picture of 'brain fog' and may help to discover its mechanisms and ways of helping people with long COVID.