One-Year Trajectory of Cognitive Changes in Older Survivors of COVID-19 in Wuhan, China: A Longitudinal Cohort Study

Long-term outcomes of patients with a pre-existing neurological condition after SARS-CoV-2 infection

OBJECTIVES

This study investigated post COVID-19 outcomes of patients with pre-existing neurological conditions up to 3.5 years post-infection.

METHODS

This retrospective study consisted of 1664 patients with COVID-19 (of which 1320 had been hospitalized for acute COVID-19) and 8985 non-COVID patients from the Montefiore Health System in the Bronx (Jan-2016 to Jul-2023). Pre-existing neurological conditions include dementia, mild cognitive impairment, multiple sclerosis, and Parkinson's disease. Primary outcomes were all-cause mortality and major adverse cardiovascular events (MACE) post-COVID-19. Secondary outcomes were depression, anxiety, fatigue, headache, sleep disturbances, altered mental status, and dyspnea post-COVID-19. Multivariate Cox proportional hazards model was used to calculate adjusted hazard ratios for primary outcomes. Cumulative incidence function and Fine-Gray sub-distribution hazards model analysis were performed for secondary outcomes.

RESULTS

Patients with a pre-existing neurological disorders hospitalized for COVID-19 were more likely to die (adjusted hazard ratio = 1.90 [CI:1.57, 2.28], P < 0.005) whereas patients non-hospitalized for COVID-19 had similar mortality rate (aHR = 0.85 [CI:0.47, 1.54]. P = 0.59) compared to non-COVID patients. Patients with a neurological disorders (hospitalized for COVID-19 aHR = 1.76 [CI:1.53, 2.03], P < 0.005; not hospitalized for COVID-19: aHR = 1.50 [CI:1.09, 2.05], P = 0.01) were more likely to experience a MACE compared to non-COVID-19 patients. Blacks (aHR = 1.49) and Hispanics (aHR = 1.35) had a higher risk of post-COVID-19 MACE. Both hospitalized and non-hospitalized COVID-19 patients were more likely to develop altered mental status, fatigue, sleep disturbance, dyspnea compared to non-COVID patients (p < 0.05).

CONCLUSIONS

Patients with pre-existing neurological conditions who contracted SARS-CoV-2 were more likely to have worse outcomes compared to controls after adjusting for major competing risks. Identifying at-risk individuals could enable more diligent follow-up.

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.

Neuropsychology practice guidance for the neuropsychiatric aspects of Long COVID

Objective: The coronavirus disease-2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has had a profound global impact on individual health and well-being in adults and children. While most fully recover from COVID-19, a relatively large subgroup continues to experience persistent physical, cognitive, and emotional/behavioral symptoms beyond the initial infection period. The World Health Organization has termed this phenomenon "Post-COVID-19 Condition" (PCC), better known as "Long COVID." Due to the cognitive and psychosocial symptoms, neuropsychologists often assess and recommend treatment for individuals with Long COVID. However, guidance for neuropsychologists' involvement in clinical care, policy-making, and research has not yet been developed. The authors of this manuscript convened to address this critical gap and develop guidance for clinical neuropsychologists working with patients presenting with Long COVID. Method: Authors include pediatric and adult neuropsychologists with expertise in Long COVID and behavioral health. All authors have been engaged in clinical and research efforts examining the impact of COVID-19. Authors summarized the literature-to-date pertinent to the neuropsychiatric sequelae of Long COVID and developed guidance for neuropsychologists working with individuals with Long COVID. Conclusions: Research findings regarding neuropsychiatric symptoms associated with Long COVID are mixed and limited by methodological differences. As they practice and conduct research, neuropsychologists should remain mindful of the evolving and tenuous nature of the literature.

Correlation Between COVID-19 Recovery, Executive Function Decline, and Emotional State

Objective

The aim of this study was to determine whether there is a relationship between the time since recovery from coronavirus disease 2019 (COVID-19) and alterations in executive functions. We also evaluate the emotional state of post-COVID-19 patients.

Patients and Methods

We assessed patients between 18 and 50 years old, who had a history of COVID-19 with mild, moderate, or severe illness. We used the Batería Neuropsicológica de Funciones Ejecutivas y Lóbulos Frontales-3 (BANFE-3), Mini-Mental State Examination (MMSE), and Mini-International Neuropsychiatric Interview (MINI), in addition to a semi-structured interview. Spearman's correlation coefficient was used, with a p value <0.05 indicating significance.

Results

We evaluated 67 patients with a mean age of 34.6±9.6 years, most of whom had ≥13 years of schooling (n=55, 82.1%). Among them, 52 (77.6%) reported persistent symptoms after resolution of the condition, with fatigue being the most frequent (n=20, 29.9%). Most participants had an adequate score on the MMSE (n=60, 89.6%). However, 19 (28.4%) showed alterations in the BANFE-3 total score, with mental flexibility as the most affected function (n=25, 37.3%). In participants from the first COVID-19 wave, a negative correlation was observed between the standardized orbitofrontal area scores and the time since recovery from the infection (r=-0.841, p=0.016), suggesting a pattern of deterioration over time, mainly in stimulus inhibition (r=0.880, p=0.021). Regarding emotional state, 45 subjects (67.2%) exhibited emotional alterations, with anxiety symptoms being the most frequent (n=33, 49.3%). Furthermore, individuals with depressive symptoms (n=32, 47.8%) were more likely to experience executive function impairment after COVID-19 (ExpB 0.302, 95% CI 0.098-0.933, p=0.038).

Conclusion

COVID-19 could lead to alterations in executive functions, probably resulting from progressive damage to orbitofrontal area functions, mainly in stimulus inhibition. However, the generalizability of these findings is limited, highlighting the need for further research with robust methodology. Furthermore, depression appears to be an indicator of cognitive impairment in individuals recovering from COVID-19. Therefore, cognitive rehabilitation and psychological support are essential for patients affected by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection.

COVID-19 Pandemic-Related Exposures and Cognitive Function in Middle-Aged Women

Importance

The COVID-19 pandemic has been associated with risk factors for cognitive decline, such as bereavement and SARS-CoV-2 infection.

Objective

To examine whether the COVID-19 pandemic and pandemic-related exposures are associated with cognitive function among middle-aged women.

Design, Setting, and Participants

This cohort study analyzed data from the Nurses' Health Study II, an ongoing study of registered nurses in the US. The present study focused on women aged 51 to 76 years who completed 2 to 8 objective cognitive assessments both prior to (October 1, 2014, to February 29, 2020) and during the COVID-19 pandemic (March 1, 2020, to September 30, 2022). Statistical analyses were performed from January 2023 to January 2025.

Exposure

COVID-19 pandemic.

Main Outcomes and Measures

Two standardized (ie, z-scored) composite cognitive scores (psychomotor speed and attention, learning and working memory) and a global score constituted the primary outcomes. Higher scores indicated better cognitive function. Cognitive function was assessed using the Cogstate Brief Battery, a computer-administered cognitive test battery. Participants completed cognitive assessments every 6 to 12 months.

Results

A total of 5191 women (mean [SD] age at first cognitive assessment, 63.0 [4.8] years) completed both prepandemic and during-pandemic measures, contributing 23 678 cognitive assessments. After adjustment for age at cognitive assessment, educational level for both participants and their parents, cognitive test practice effects, and comorbidities (eg, diabetes, hypertension), no difference in cognitive function was observed between assessments taken during vs before the pandemic (psychomotor speed and attention: β = -0.01 SD [95% CI, -0.05 to 0.02 SD]; learning and working memory: β = 0.00 SD [95% CI, -0.03 to 0.03 SD]; global score: β = 0.00 SD [95% CI, -0.03 to 0.02 SD]). Among 4456 participants who responded to the COVID-19 substudy (ie, surveys about pandemic-related events), those with a history of SARS-CoV-2 infection (164 [3.7%]) or post-COVID-19 conditions (PCC; 62 [1.4%]), at a median (IQR) 20.0 (18.5-22.1) months after initial infection, had reduced cognitive function compared with women without infection or PCC; however, these differences did not reach statistical significance, and the wide CIs suggested considerable uncertainty.

Conclusions and Relevance

This cohort study of middle-aged women found that the COVID-19 pandemic and pandemic-related events were not associated with cognitive decline up to 2.5 years after the onset of the pandemic. Future studies are needed to examine the long-term implications of SARS-CoV-2 infection and PCC for cognitive function.

Identifying risk factors and predicting long COVID in a Spanish cohort

Many studies have investigated symptoms, comorbidities, demographic factors, and vaccine effects in relation to long COVID (LC-19) across global populations. However, a number of these studies have shortcomings, such as inadequate LC-19 categorisation, lack of sex disaggregation, or a narrow focus on certain risk factors like symptoms or comorbidities alone. We address these gaps by investigating the demographic factors, comorbidities, and symptoms present during the acute phase of primary COVID-19 infection among patients with LC-19 and comparing them to typical non-Long COVID-19 patients. Additionally, we assess the impact of COVID-19 vaccination on these patients. Drawing on data from the Regional Health System of the Region of Murcia in southeastern Spain, our analysis includes comprehensive information from clinical and hospitalisation records, symptoms, and vaccination details of over 675126 patients across 10 hospitals. We calculated age and sex-adjusted odds ratios (AOR) to identify protective and risk factors for LC-19. Our findings reveal distinct symptomatology, comorbidity patterns, and demographic characteristics among patients with LC-19 versus those with typical non-Long COVID-19. Factors such as age, female sex (AOR = 1.39, adjusted p < 0.001), and symptoms like chest pain (AOR > 1.55, adjusted p < 0.001) or hyposmia (AOR > 1.5, adjusted p < 0.001) significantly increase the risk of developing LC-19. However, vaccination demonstrates a strong protective effect, with vaccinated individuals having a markedly lower risk (AOR = 0.10, adjusted p < 0.001), highlighting the importance of vaccination in reducing LC-19 susceptibility. Interestingly, symptoms and comorbidities show no significant differences when disaggregated by type of LC-19 patient. Vaccination before infection is the most important factor and notably decreases the likelihood of long COVID. Particularly, mRNA vaccines offer more protection against developing LC-19 than viral vector-based vaccines (AOR = 0.48). Additionally, we have developed a model to predict LC-19 that incorporates all studied risk factors, achieving a balanced accuracy of 73% and ROC-AUC of 0.80. This model is available as a free online LC-19 calculator, accessible at ( LC-19 Calculator ).

Antiageing strategy for neurodegenerative diseases: from mechanisms to clinical advances

In the context of global ageing, the prevalence of neurodegenerative diseases and dementia, such as Alzheimer's disease (AD), is increasing. However, the current symptomatic and disease-modifying therapies have achieved limited benefits for neurodegenerative diseases in clinical settings. Halting the progress of neurodegeneration and cognitive decline or even improving impaired cognition and function are the clinically meaningful goals of treatments for neurodegenerative diseases. Ageing is the primary risk factor for neurodegenerative diseases and their associated comorbidities, such as vascular pathologies, in elderly individuals. Thus, we aim to elucidate the role of ageing in neurodegenerative diseases from the perspective of a complex system, in which the brain is the core and peripheral organs and tissues form a holistic network to support brain functions. During ageing, the progressive deterioration of the structure and function of the entire body hampers its active and adaptive responses to various stimuli, thereby rendering individuals more vulnerable to neurodegenerative diseases. Consequently, we propose that the prevention and treatment of neurodegenerative diseases should be grounded in holistic antiageing and rejuvenation means complemented by interventions targeting disease-specific pathogenic events. This integrated approach is a promising strategy to effectively prevent, pause or slow down the progression of neurodegenerative diseases.

Risk of new-onset dementia following COVID-19 infection: a systematic review and meta-analysis

BACKGROUND

Emerging evidence suggests coronavirus disease 2019 (COVID-19) infection may increase the risk of developing dementia, although studies have reported conflicting findings. This meta-analysis aimed to synthesise the literature on the association between COVID-19 and the risk of new-onset dementia.

METHODS

PubMed, Embase and Web of Science were searched for cohort studies or case-control studies that investigated new-onset dementia development among adult COVID-19 survivors compared to individuals without COVID-19 infection from inception to 9 November 2023. Studies that exclusively involved populations younger than 18 years, with known dementia or lacked adequate data about the risk of dementia were excluded. Two authors independently conducted the screening of eligible studies, data extraction and risk of bias assessment. The primary outcome was new-onset dementia following COVID-19 infection. Data were pooled using random-effects models, with hazard ratios (HRs) and 95% confidence intervals (CIs) calculated.

RESULTS

A total of 15 retrospective cohort studies encompassing 26 408 378 participants were included. Pooled analysis indicated COVID-19 was associated with an increased risk of new-onset dementia (HR = 1.49, 95% CI: 1.33-1.68). This risk remained elevated when compared with non-COVID cohorts (HR = 1.65, 95% CI: 1.39-1.95), and respiratory tract infection cohorts (HR = 1.29, 95% CI: 1.12-1.49), but not influenza or sepsis cohorts. Increased dementia risk was observed in both males and females, as well as in individuals older than 65 years (HR = 1.68, 95% CI: 1.48-1.90), with the risk remaining elevated for up to 24 months.

CONCLUSION

This meta-analysis demonstrates a significant association between COVID-19 infection and increased risk of developing new-onset dementia, which underscores the need for cognitive monitoring and early intervention for COVID-19 survivors to address potential long-term neurological impacts.

Global prevalence of post-COVID-19 condition: a systematic review and meta-analysis of prospective evidence

INTRODUCTION

We investigated the prevalence of new or persistent manifestations experienced by COVID-19 survivors at 3 or more months after their initial infection, collectively known as post-COVID-19 condition (PCC).

METHODS

We searched four electronic databases and major grey literature resources for prospective studies, systematic reviews, authoritative reports and population surveys. A random-effects meta-analysis pooled the prevalence data of 22 symptoms and outcomes. The GRADE approach was used to assess the certainty of evidence. PROSPERO CRD42021231476.

RESULTS

Of 20 731 identified references, 194 met our inclusion criteria. These studies followed 483 531 individuals with confirmed COVID-19 diagnosis over periods of up to 2 years. Most focused on adults, nearly two-thirds were conducted in Europe and 63% were of high or moderate quality. The supplementary search identified 17 systematic reviews, five authoritative reports and four population surveys that reported on PCC prevalence. Our analysis revealed that more than half of COVID-19 survivors experienced one or more symptoms more than a year after their initial infection. The most common symptoms were fatiguedyspneamemory, sleep or concentration disturbances; depressionand pain. Limitation in returning to work was the most common outcome. Prevalence tended to be higher among females, individuals hospitalized during their initial infection and those who experienced severe COVID-19 illness.

CONCLUSION

PCC presents a significant health burden, affecting some groups more than others. This information will help inform health care system policies and services for people living with PCC and those caring for them.

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.

2025 Heart Disease and Stroke Statistics: A Report of US and Global Data From the American Heart Association

BACKGROUND

The American Heart Association (AHA), in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, nutrition, sleep, and obesity) and health factors (cholesterol, blood pressure, glucose control, and metabolic syndrome) that contribute to cardiovascular health. The AHA Heart Disease and Stroke Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, brain health, complications of pregnancy, kidney disease, congenital heart disease, rhythm disorders, sudden cardiac arrest, subclinical atherosclerosis, coronary heart disease, cardiomyopathy, heart failure, valvular disease, venous thromboembolism, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The AHA, through its Epidemiology and Prevention Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States and globally to provide the most current information available in the annual Statistical Update with review of published literature through the year before writing. The 2025 AHA Statistical Update is the product of a full year's worth of effort in 2024 by dedicated volunteer clinicians and scientists, committed government professionals, and AHA staff members. This year's edition includes a continued focus on health equity across several key domains and enhanced global data that reflect improved methods and incorporation of ≈3000 new data sources since last year's Statistical Update.

RESULTS

Each of the chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policymakers, media professionals, clinicians, health care administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

Closing the gap in dementia research by community-based cohort studies in the Chinese population

China accounts for 1/5 of the global population and China faces a particularly heavy dementia burden due to its rapidly ageing population. Unique historical events, genetic background, sociocultural factors, lifestyle, and the COVID-19 pandemic further influence cognitive outcomes in the Chinese population. We searched PubMed, Web of Science, and Embase for community-based cohort studies related to dementia in the Chinese population, and summarized the characteristics, methodologies, and major findings published over the last 25 years from 39 cohorts. We identified critical research gaps and propose future directions, including enhancing sample representativeness, investigating China-specific risk factors, expanding exposure measurements to the whole life-span, collecting objective data, conducting administer-friendly domain-specific cognitive assessments, adopting pathological diagnostic criteria, standardizing biobank construction, verifying multi-modal biomarkers, examining social and genetic-environmental aspects, and monitoring post-COVID cognitive health, to approach high quality of dementia studies that can provide solid evidence to policy making and promote global brain health research.

Association between post-COVID-19 sleep disturbance and neurocognitive function: a comparative study based on propensity score matching

Despite that sleep disturbance and poor neurocognitive performance are common complaints among coronavirus disease 2019 (COVID-19) survivors, few studies have focused on the effect of post-COVID-19 sleep disturbance (PCSD) on cognitive function. This study aimed to identify the impact of PCSD on neurocognitive function and explore the associated risk factors for the worsening of this condition. This cross-sectional study was conducted via the web-based assessment in Chinese mainland. Neurocognitive function was evaluated by the modified online Integrated Cognitive Assessment (ICA) and the Number Ordering Test (NOT). Propensity score matching (PSM) was utilized to match the confounding factors between individuals with and without PCSD. Univariate analyses were performed to evaluate the effect of PCSD on neurocognitive function. The risk factors associated with worsened neurocognitive performance in PCSD individuals were explored using binary logistic regression. A total of 8692 individuals with COVID-19 diagnosis were selected for this study. Nearly half (48.80%) of the COVID-19 survivors reported sleep disturbance. After matching by PSM, a total of 3977 pairs (7954 individuals in total) were obtained. Univariate analyses revealed that PCSD was related to worse ICA and NOT performance (P<0.05). Underlying disease, upper respiratory infection, loss of smell or taste, severe pneumonia, and self-reported cognitive complaints were associated with worsened neurocognitive performance among PCSD individuals (P<0.05). Furthermore, aging, ethnicity (minority), and lower education level were found to be independent risk factors for worsened neurocognitive performance in PCSD individuals (P<0.05). PCSD was related to impaired neurocognitive performance. Therefore, appropriate prevention and intervention measures should be taken to minimize or prevent PCSD and eliminate its potential adverse effect on neurocognitive function.

The short-term impacts of COVID-2019 on depressive symptoms and cognitive decline: A community-based cohort study

Background

Neurological and psychological sequelae may persist after the infection of coronavirus disease 2019 (COVID-19). Depression and cognitive decline could increase the risk of Alzheimer's disease.

Objective

To estimate the impacts of COVID-19 on depressive symptoms and cognitive decline.

Methods

The data was from Beijing Research on Ageing and Vessel (BRAVE), which included all residents in the Xishan community. The first wave survey was performed from October to November 2019 (baseline) before the COVID-19 pandemic. The second wave survey was interrupted into two periods due to the introduction of the Ten New Measures, from October to November 2022 (no participants were infected) and from March to April 2023 (most participants were infected), providing an excellent opportunity to investigate the short-term impacts of COVID-19 on depressive symptoms and cognitive function with linear mixed models.

Results

Among a total of 1012 participants, the median (interquartile range, IQR) age at baseline was 60.00 (56.00, 65.00) years, with 374 (36.96%) men and 479 participants COVID-19 infected. Compared with uninfected participants, the infected did not suffer pronounced depressive symptoms (β = -0.047; 95% CI -0.204 to 0.110) and accelerated declines in global cognition (β = 0.116; 95% CI -0.001 to 0.234) from wave 1 to wave 2. Sensitive analyses shared generally consistent findings.

Conclusions

The impacts of COVID-19 infection on depressive symptoms and cognitive decline were not significant among participants in the BRAVE cohort. Further research is needed to investigate the long-term impacts on neurological and psychiatric symptoms.

Acute and long-term effects of COVID-19 on brain and mental health: A narrative review

BACKGROUND

COVID infection has been associated with long term sequalae (Long COVID) which include neurological and behavioral effects in thousands of patients, but the etiology and scope of symptoms is not well understood. This paper reviews long term sequelae of COVID on brain and mental health in patients with the Long COVID syndrome.

METHODS

This was a literature review which queried databases for Pubmed, Psychinfo, and Medline for the following topics for January 1, 2020-July 15, 2023: Long COVID, PASC, brain, brain imaging, neurological, neurobiology, mental health, anxiety, depression.

RESULTS

Tens of thousands of patients have developed Long COVID, with the most common neurobehavioral symptoms anosmia (loss of smell) and fatigue. Anxiety and mood disorders are elevated and seen in about 25% of Long COVID patients. Neuropsychological testing studies show a correlation between symptom severity and cognitive dysfunction, while brain imaging studies show global decreases in gray matter and alterations in olfactory and other brain areas.

CONCLUSIONS

Studies to date show an increase in neurobehavioral disturbances in patients with Long COVID. Future research is needed to determine mechanisms.

SARS-CoV-2 membrane protein induces neurodegeneration via affecting Golgi-mitochondria interaction

BACKGROUND

Neurological complications are a significant concern of Coronavirus Disease 2019 (COVID-19). However, the pathogenic mechanism of neurological symptoms associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is poorly understood.

METHODS

We used Drosophila as a model to systematically analyze SARS-CoV-2 genes encoding structural and accessory proteins and identified the membrane protein (M) that disrupted mitochondrial functions in vivo. The M protein was stereotaxically injected to further assess its effects in the brains of wild-type (WT) and 5 × FAD mice. Omics technologies, including RNA sequencing and interactome analysis, were performed to explore the mechanisms of the effects of M protein both in vitro and in vivo.

RESULTS

Systematic analysis of SARS-CoV-2 structural and accessory proteins in Drosophila identified that the M protein induces mitochondrial fragmentation and dysfunction, leading to reduced ATP production, ROS overproduction, and eventually cell death in the indirect flight muscles. In WT mice, M caused hippocampal atrophy, neural apoptosis, glial activation, and mitochondrial damage. These changes were further aggravated in 5 × FAD mice. M was localized to the Golgi apparatus and genetically interacted with four wheel drive (FWD, a Drosophila homolog of mammalian PI4KIIIβ) to regulate Golgi functions in flies. Fwd RNAi, but not PI4KIIIα RNAi, reversed the M-induced Golgi abnormality, mitochondrial fragmentation, and ATP reduction. Inhibition of PI4KIIIβ activity suppressed the M-induced neuronal cell death. Therefore, M induced mitochondrial fragmentation and apoptosis likely through disruption of Golgi-derived PI(4)P-containing vesicles.

CONCLUSIONS

M disturbs the distribution and function of Golgi, leading to mitochondrial abnormality and eventually neurodegeneration via a PI4KIIIβ-mediated mechanism. This study reveals a potential mechanism for COVID-19 neurological symptoms and opens a new avenue for development of therapeutic strategies targeting SARS-CoV-2 M or mitochondria.

Association between COVID-19 infection and new-onset dementia in older adults: a systematic review and meta-analysis

BACKGROUND

The relationship between COVID-19 infection and a possible increased likelihood of older adults developing new-onset dementia (NOD) remains elusive.

METHODS

A thorough search was performed across several databases including MEDLINE/PubMed, PsycINFO, Scopus, medRxiv, and PQDT Global for studies published in English from January 2020 to December 2023. Only original investigations exploring the link between COVID-19 infection and NOD were selected for inclusion. We assessed the risk of developing NOD, using Risk Ratio (RR) for measurement. Control groups were categorized as: (i) a non-COVID cohort with other respiratory infections [control group (C1)]; and (ii) a non-COVID cohort with otherwise unspecified health status [control group (C2)]. Follow-up periods were divided into intervals of 3, 6, 12, and 24 months post-COVID.

RESULTS

11 studies (involving 939,824 post-COVID-19 survivors and 6,765,117 controls) were included in the review. Across a median observation period of 12 months post-COVID, the overall incidence of NOD was about 1.82% in the COVID-infected group, compared to 0.35% in the non-COVID-infected group. The overall pooled meta-analysis showed a significantly increased NOD risk among COVID-19 older adult survivors compared to non-COVID-19 controls (RR = 1.58, 95% CI 1.21-2.08). Similar increased NOD risks were observed in subgroup analyses restricted to an observational period of 12 months (RR = 1.56, 95% CI 1.21-2.01), as well as in five studies that employed propensity score matching to sufficiently and effectively control for multiple confounding covariates (RR = 1.46, 95% CI 1.10-1.94). COVID-19 group and C1 group shared a comparably increased risk of developing NOD (overall RR = 1.13, 95% CI 0.92-1.38).

DISCUSSION

Under normal circumstances, we believe that COVID-19 infection is likely to be a risk factor for developing NOD in older adults over time. While the increased NOD risk due to COVID-19 infection appears to be similar to that associated with other respiratory infections, it warrants and necessitates investigation with longer observations.

Long-Term Trajectories of Cognitive Disability Among Older Adults Following a Major Disaster

Importance

Older adults are at high risk for cognitive impairments following natural disasters, but the persistence of such effects is not well understood.

Objective

To track older adults' postdisaster cognitive disability trajectories over a decade and examine associations of cognitive disability with disaster damage exposure.

Design, Setting, and Participants

This prospective cohort study used predisaster baseline surveys conducted in August 2010 and 4 follow-ups approximately every 3 years until November 10, 2022. Invitations were mailed at baseline to all citizens 65 years or older in Iwanuma City, Japan, a coastal municipality significantly impacted by the 2011 Great East Japan Earthquake and Tsunami. A total of 1988 respondents who were cognitively independent (ie, without cognitive disability) before the disaster completed the 4 postdisaster cognitive assessments.

Exposures

Experiences of residential damage, worsening financial conditions, loss of loved ones, and disruption in health care services. A composite score quantified these experiences, with higher scores indicating greater overall damage.

Main Outcomes and Measures

Cognitive disability level was assessed using a standardized in-home evaluation under a national long-term care insurance scheme. Trained investigators evaluated participants' activities of daily living, cognitive function, and presence of mental and/or behavioral disorders. Latent class growth analyses (LCGA) identified distinct cognitive disability trajectories. Primary outcomes consisted of inclusion in these trajectories.

Results

The analytic sample consisted of 1988 participants who were cognitively independent at baseline, with a mean (SD) age of 72.4 (5.4) years, of whom 1159 (58.3%) were female. LCGA identified 3 cognitive disability trajectories: high and gradual deterioration (277 [13.9%]; high levels of cognitive disability with increasing impairment over time), low and progressive deterioration (541 [27.2%]; low levels of cognitive disability with accelerated decline in cognitive function over time), and low and stable (1170 [58.9%]; low levels of cognitive disability that remained stable). In multinomial regression analyses with the low and stable trajectory serving as the reference, housing damage (adjusted odds ratio [AOR], 2.52; 95% CI, 1.26-5.04), worsening financial conditions (AOR, 1.83; 95% CI, 1.15-2.90), and disruption in health care services (AOR, 1.76; 95% CI, 1.03-2.99) were associated with high and gradual deterioration. Worsening financial conditions (AOR, 1.38; 95% CI, 1.01-1.90) and higher composite damage scores (AOR, 1.16; 95% CI, 1.01-1.34) were associated with low and progressive deterioration. These associations no longer remained after adjusting for postdisaster depressive symptoms.

Conclusions and Relevance

In this cohort study of older adults who survived the 2011 Great East Japan Earthquake and Tsunami, disaster-related exposures were associated with worse long-term cognitive disability trajectories. These findings could inform tailored interventions to preserve cognitive function in older disaster survivors.

The population based cognitive testing in subjects with SARS-CoV-2 (POPCOV2) study: longitudinal investigation of remote cognitive and fatigue screening in PCR-positive cases and negative controls

Background

The majority of people infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) only show mild respiratory symptoms. However, some patients with SARS-CoV-2 display neurological symptoms. Data on the exact prevalence and course of cognitive symptoms are often limited to patient reported outcomes or studies recruited at specialized centers.

Methods

For this prospective, non-interventional population based POPCOV2 study, 156 subjects who performed SARS-CoV-2 testing in the Düsseldorf metropolitan area at public test centers between December 2020 and February 2022 were recruited by handouts. SARS-CoV-2-positive and negatively tested subjects were included within the first seven days after the PCR test results. Cognitive testing was performed at baseline during home quarantine and after 4-6 as well as 12-14 weeks of follow-up. Individuals were examined remotely by videocalls using the Symbol Digit Modalities Test (SDMT) and the Montreal Cognitive Assessment (MoCA) in addition to the Brief Fatigue Inventory (BFI) and the Beck Depression Inventory-Fast Screen (BDI-FS).

Results

At baseline, the SARS-CoV-2-positive group presented with higher levels of fatigue in the BFI. In both the SARS-CoV-2-positive and SARS-CoV-2-negative groups, some subjects presented attention and memory deficits, defined as a z-score < -1,65 on the SDMT or < 26 points on the MoCA (SDMT: 22.9% in the positive and 8.8% in the negative group, p = 0.024; MoCA: 35.6% in the positive and 27.3% in the negative group, p = 0.313). MoCA and SDMT improved over time in both groups. For MoCA scores, a significant difference between the two groups was only seen at the first follow-up. SDMT z-scores did not differ at any time between the groups.

Conclusion

These results support previous evidence that mild SARS-CoV-2 infections are associated with increased fatigue. However, we found relevant rates of cognitive impairment not only in the infected but also in the control group. This underlines the importance of including a control group in such investigations.

Long COVID and recovery from Long COVID: quality of life impairments and subjective cognitive decline at a median of 2 years after initial infection

BACKGROUND

Recovery from SARS CoV-2 infection is expected within 3 months. Long COVID occurs after SARS-CoV-2 when symptoms are present for more than 3 months that are continuous, relapsing and remitting, or progressive. Better understanding of Long COVID illness trajectories could strengthen patient care and support.

METHODS

We characterized functional impairments, quality of life (QoL), and cognition among patients who recovered from SARS-CoV-2 infection within 3 months (without Long COVID), after 3 months (Recovered Long COVID), or remained symptomatic (Long COVID). Among 7305 patients identified with previous SARS-CoV-2 infection between March 2020 and December 2021, confirmed in the medical record with laboratory test or physician diagnosis, 435 (6%) completed a single self-administered survey between March 2022 and September 2022. Multi-domain QoL and cognitive concerns were evaluated using PROMIS-29 and the Cognitive Change Index-12.

RESULTS

Nearly half the participants (47.7%) were surveyed more than 2 years from initial infection (median = 23.3 months; IQR = 18.6, 26.7) and 86.7% were surveyed more than 1 year from infection. A significantly greater proportion of the Long COVID (n = 215) group, (Current and Recovered combined), had moderate-to-severe impairment in all health domains assessed compared to those Without Long COVID (n = 220; all p < 0.05). The Recovered Long COVID group (n = 34) had significantly lower prevalence of fatigue, pain, depression, and physical and social function impairment compared to those with Current Long COVID (n = 181; all p < 0.05). However, compared to patients Without Long COVID, the Recovered Long COVID group had greater prevalences of fatigue, pain (p ≤ 0.06) and subjective cognitive decline (61.8% vs 29.1%; p < 0.01). Multivariate relative risk (RR) regression indicated Long COVID risk was greater for older age groups (RR range 1.46-1.52; all p ≤ 0.05), those without a bachelor's degree (RR = 1.33; 95% CI = 1.03-1.71; p = 0.03), and those with 3 or more comorbidities prior to SARS-CoV-2 infection (RR = 1.45; 95% CI = 1.11-1.90; p < 0.01).

CONCLUSIONS

Long COVID is associated with long-term subjective cognitive decline and diminished quality of life. Clinically significant cognitive complaints, fatigue, and pain were present even in those who reported they had recovered from Long COVID. These findings have implications for the sustainability of participation in work, education, and social activities.

The risk of cognitive decline and dementia in older adults diagnosed with COVID-19: A systematic review and meta-analysis

BACKGROUND

Cognitive impairment can be caused by infections with various pathogens, including SARS-CoV-2. Research has yet to determine the true incidence and course of cognitive impairment in older adults following COVID-19. Furthermore, research has theorised that COVID-19 is associated with dementia progression and diagnosis but this association has yet to be fully described.

METHODS

A systematic review was registered in Prospero and conducted on the databases PubMed, Embase, Ovid, CENTRAL and Cochrane Library. Studies reporting cognitive impairment and dementia outcomes in post-acute and post-COVID-19 patients aged ≥65 years, and which included control data, were included in this review.

RESULTS

15,124 articles were identified by the search strategy. After eliminating duplicate titles and completing title, abstracts and full-text review, 18 studies were included comprising of 412,957 patients with COVID-19 (46.63 % male) and 411,929 patients without COVID-19 (46.59 % male). The overall mean Montreal Cognitive Assessment (MoCA) score in COVID-19 patients was 23.34 out of 30 (95 % CI [22.24, 24.43]). indicating cognitive impairment. The overall proportion of patients identified as having new onset cognitive impairment was 65 % (95 % CI [44,81]). Subgroup analyses indicated that time since infection significantly improves overall MoCA score and reduces proportion of patients with cognitive impairment.

CONCLUSION

This study indicates that cognitive impairment may be an important sequela of COVID-19. Further research with adequate sample sizes is warranted regarding COVID-19's association with new-onset dementia and dementia progression, and the effect of repeat infections. There is a need for development of diagnostic and management protocols for COVID-19 patients with cognitive impairment.

Changes in memory and cognition during the SARS-CoV-2 human challenge study

Background

Patient-reported outcomes and cross-sectional evidence show an association between COVID-19 and persistent cognitive problems. The causal basis, longevity and domain specificity of this association is unclear due to population variability in baseline cognitive abilities, vulnerabilities, virus variants, vaccination status and treatment.

Methods

Thirty-four young, healthy, seronegative volunteers were inoculated with Wildtype SARS-CoV-2 under prospectively controlled conditions. Volunteers completed daily physiological measurements and computerised cognitive tasks during quarantine and follow-up at 30, 90, 180, 270, and 360 days. Linear modelling examined differences between 'infected' and 'inoculated but uninfected' individuals. The main cognitive endpoint was the baseline corrected global cognitive composite score across the battery of tasks administered to the volunteers. Exploratory cognitive endpoints included baseline corrected scores from individual tasks. The study was registered on ClinicalTrials.gov with the identifier NCT04865237 and took place between March 2021 and July 2022.

Findings

Eighteen volunteers developed infection by qPCR criteria of sustained viral load, one without symptoms and the remainder with mild illness. Infected volunteers showed statistically lower baseline-corrected global composite cognitive scores than uninfected volunteers, both acutely and during follow up (mean difference over all time points = -0.8631, 95% CI = -1.3613, -0.3766) with significant main effect of group in repeated measures ANOVA (F (1,34) = 7.58, p = 0.009). Sensitivity analysis replicated this cross-group difference after controlling for community upper respiratory tract infection, task-learning, remdesivir treatment, baseline reference and model structure. Memory and executive function tasks showed the largest between-group differences. No volunteers reported persistent subjective cognitive symptoms.

Interpretation

These results support larger cross sectional findings indicating that mild Wildtype SARS-CoV-2 infection can be followed by small changes in cognition and memory that persist for at least a year. The mechanistic basis and clinical implications of these small changes remain unclear.

Funding

This study was funded through the UK Vaccine Taskforce of the Department for Business, Energy and Industrial Strategy (BEIS) of Her Majesty's Government. WT was funded by the EPSRC through the CDT for Neurotechnology Imperial College London.

Research evidence on the management of the cognitive impairment component of the post-COVID condition: a qualitative systematic review

BACKGROUND

Cognitive impairment (CI) is one of the most prevalent and burdensome consequences of COVID-19 infection, which can persist up to months or even years after remission of the infection. Current guidelines on post-COVID CI are based on available knowledge on treatments used for improving CI in other conditions. The current review aims to provide an updated overview of the existing evidence on the efficacy of treatments for post-COVID CI.

METHODS

A systematic literature search was conducted for studies published up to December 2023 using three databases (PubMed-Scopus-ProQuest). Controlled and noncontrolled trials, cohort studies, case series, and reports testing interventions on subjects with CI following COVID-19 infection were included.

RESULTS

After screening 7790 articles, 29 studies were included. Multidisciplinary approaches, particularly those combining cognitive remediation interventions, physical exercise, and dietary and sleep support, may improve CI and address the different needs of individuals with post-COVID-19 condition. Cognitive remediation interventions can provide a safe, cost-effective option and may be tailored to deficits in specific cognitive domains. Noninvasive brain stimulation techniques and hyperbaric oxygen therapy showed mixed and preliminary results. Evidence for other interventions, including pharmacological ones, remains sparse. Challenges in interpreting existing evidence include heterogeneity in study designs, assessment tools, and recruitment criteria; lack of long-term follow-up; and under-characterization of samples in relation to confounding factors.

CONCLUSIONS

Further research, grounded on shared definitions of the post-COVID condition and on the accurate assessment of COVID-related CI, in well-defined study samples and with longer follow-ups, is crucial to address this significant unmet need.

Tracking cognitive trajectories in older survivors of COVID-19 up to 2.5 years post-infection

Emerging evidence suggests that neurological and other post-acute sequelae of COVID-19 can persist beyond or develop following SARS-CoV-2 infection. However, the long-term trajectories of cognitive change after a COVID-19 infection remain unclear. Here we investigated cognitive changes over a period of 2.5 years among 1,245 individuals aged 60 years or older who survived infection with the original SARS-CoV-2 strain in Wuhan, China, and 358 uninfected spouses. We show that the overall incidence of cognitive impairment among older COVID-19 survivors was 19.1% at 2.5 years after infection and hospitalization, evaluated using the Telephone Interview for Cognitive Status-40. Cognitive decline primarily manifested in individuals with severe COVID-19 during the initial year of infection, after which the rate of decline decelerated. Severe COVID-19, cognitive impairment at 6 months and hypertension were associated with long-term cognitive decline. These findings reveal the long-term cognitive trajectory of the disease and underscore the importance of post-infection cognitive care for COVID-19 survivors.

Objective and subjective cognitive outcomes one year after COVID-19

OBJECTIVE

This study aimed to evaluate subjective cognitive, physical, and mental health symptoms as well as objective cognitive deficits in COVID-19 patients 1 year after infection.

METHODS

This was a cross-sectional study. Seventy-four patients, who contracted a SARS-CoV-2 infection in 2020, underwent an in-person neuropsychological assessment in 2021. This included standardized tests of memory, attention, and executive functions. In addition, participants also responded to scales on subjective attention deficits, mental health symptoms, and fatigue. Patients' scores were compared to published norms.

RESULTS

Patients (N = 74) had a median age of 56 years (42% female). According to the initial disease severity, they were classified as mild (outpatients, 32%), moderate (hospitalized, non-ICU-admitted, 45%), or severe (ICU-admitted, 23%). Hospitalized patients were more often affected than outpatients. In general, deficits were most common in attention (23%), followed by memory (15%) and executive functions (3%). Patients reported increased levels of fatigue (51%), anxiety (30%), distractibility in everyday situations (20%), and depression (15%). An additional analysis suggested an association between lower scores in an attention task and hyperferritinemia. As indicated by a hierarchical regression analysis, subjective distractibility was significantly predicted by current anxiety and fatigue symptoms but not by objective attention performance (final model, adj-R 2 = 0.588, P < 0.001).

INTERPRETATION

One year after infection, COVID-19 patients can have frequent attention deficits and can complain about symptoms such as fatigue, anxiety, and distractibility. Anxiety and fatigue, more than objective cognitive deficits, have an impact on the patients' experienced impairments in everyday life.

The risk of geriatric syndromes in older COVID-19 survivors among the nonvaccinated population: a real world retrospective cohort study

BACKGROUND

We aimed to analyse the differences in the risk of geriatric syndromes between older adults with and without coronavirus disease 2019 (COVID-19).

METHODS

We conducted a retrospective cohort study of patients from the US Collaborative Network in the TriNetX between January 1, 2020, and December 31, 2022. We included individuals aged older than 65 years with at least 2 health care visits who underwent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) polymerase chain reaction (PCR) tests during the study period. We excluded those with SARS-CoV-2 vaccination, diagnosis with neoplasm and geriatric syndromes before the index date, and death within 30 days after the index date. The index date was defined as the first date of the PCR test for SARS-CoV-2 during the study period. Hazard ratios (HRs) and 95% confidence intervals (CIs) for eight geriatric syndromes were estimated for propensity score-matched older adults with and without COVID-19. Subgroup analyses of sex and age were also performed.

RESULTS

After propensity score matching, 315 826 patients were included (mean [standard deviation] age, 73.5 [6.4] years; 46.7% males and 51.7% females). The three greatest relative increases in the risk of geriatric syndromes in the COVID-19 cohort were cognitive impairment (HR: 3.13; 95% CI: 2.96-3.31), depressive disorder (HR: 2.72; 95% CI: 2.62-2.82) and pressure injury (HR: 2.52; 95% CI: 2.34-2.71).

CONCLUSIONS

The risk of developing geriatric syndromes is much higher in the COVID-19 cohort. It is imperative that clinicians endeavour to prevent or minimise the development of these syndromes in the post-COVID-19 era.

Mental health problems raise the odds of cognitive impairment in COVID-19 survivors

Background

COVID-19 survivors around the globe are suffering from mental health issues. While mental health problems can be an early warning sign of dementia, they may also increase the chances of developing the disease. In this study, we examined the mental health of COVID-19 survivors and mapped its associations with cognitive and demographic variables.

Method

COVID-19 survivors listed in the databases of three tertiary care hospitals in Kolkata were contacted sequentially. 376 willing patients were interviewed over the telephone. 99 COVID-19 patients and 31 matched controls participated in the in-person interviews that were arranged for a more detailed investigation. The participants were administered standardized tests that are widely used for the assessment of cognitive functioning and mental health status.

Result

64.89% of COVID-19 survivors reported a deterioration in physical functioning. 44.95% reported a decline in mental health, whereas 41.49% reported a drop in cognitive performance. Detailed investigations revealed that they had an increased risk of having depression, anxiety, and poor sleep quality by 91%, 68%, and 140%, respectively. 6.1% of the patients had mild cognitive impairment, and 4% had dementia. COVID-19 patients who had depression and anxiety were 8.6 and 19.4 times more likely to have cognitive decline, respectively. Compared to the matched controls, COVID-19 patients had greater depression (p<.001), anxiety (p<.001), stress (p =.003), and insomnia (p <.001). They also scored significantly lower on Addenbrooke's Cognitive Examination-III (p =.009) and Picture Naming Test (p =.005) and took significantly longer to complete Trail Making Test-A (p =.002).

Conclusion

COVID-19 survivors in this study had major mental health issues even one year after contracting the virus. They had significant cognitive deficits that might progress into dementia. Strict monitoring and systematic treatment plans should be implemented as soon as possible.

Psychosocial Factors Associated With Long-Term Cognitive Impairment Among COVID-19 Survivors: A Cross-Sectional Study

ABSTRACT

COVID-19 survivors complained of the experience of cognitive impairments, which also called "brain fog" even recovered. The study aimed to describe long-term cognitive change and determine psychosocial factors in COVID-19 survivors. A cross-sectional study was recruited 285 participants from February 2020 to April 2020 in 17 hospitals in Sichuan Province. Cognitive function, variables indicative of the virus infection itself, and psychosocial variables were collected by telephone interview. Univariate logistic regression and Lasso logistic regression models were used for variable selection which plugged into a multiple logistics model. Overall prevalence of moderate or severe cognitive impairment was 6.3%. Logistic regression showed that sex, religion, smoking status, occupation, self-perceived severity of illness, sleep quality, perceived mental distress after COVID-19, perceived discrimination from relatives and friends, and suffered abuse were associated with cognitive impairment. The long-term consequences of cognitive function are related to multiple domains, in which psychosocial factors should be taken into consideration.

A pilot study to assess blood-brain barrier permeability in long COVID

The etiology of brain fog associated with long COVID is not clear. Based on some preliminary work, disruption of the blood-brain barrier has been hypothesized, but has not been tested in patients with long COVID. In this case-control pilot study, we evaluated blood-brain barrier permeability in patients with long COVID and subjective memory loss or brain fog. We used 99 m Technetium diethylenetriaminepentaacetic acid single-photon emission computed tomography (SPECT) to measure blood-brain barrier permeability and a telephone assessment (T-cog) to measure cognitive function. The blood-brain barrier permeability was quantified via SPECT standard uptake value (SUV). We assessed the blood-brain barrier permeability in 14 long COVID patients and 10 control participants without subjective cognitive impairment or brain fog. Participants in the two groups were similar in age. The long COVID group had more comorbidities compared to the control group. There was no difference in the SUVs in the long COVID (0.22 ± 0.12) vs the control (0.17 ± 0.04) group. There was no difference in the T-cog results in the two groups either. We found no evidence of a difference in blood-brain permeability in patients with long COVID when compared to controls without a known history of COVID-19 infection. Larger studies are needed to confirm these findings.

Peripheral immunity is associated with cognitive impairment after acute minor ischemic stroke and transient ischemic attack

Immunoinflammation is associated with the development of post-stroke cognitive impairment (PSCI), however, peripheral immunity has not been fully explored. We aimed to investigate the association between PSCI and peripheral immune indicators, including neutrophil, lymphocyte, and mononuclear percentages and counts; the systemic immune inflammation index; platelet-to-lymphocyte ratio; neutrophil-to-lymphocyte ratio (NLR); and lymphocyte-to-monocyte ratio. A total of 224 patients with acute minor ischemic stroke or transient ischemic attack with 6-12 months of follow-up were included. PSCI was defined as a Montreal Cognitive Assessment score < 22 during the follow-up period. We performed logistic regression, subgroup analyses based on age and sex, and further established predictive models. We found that increased innate immunity indicators (neutrophils, neutrophil percentage) increased the risk of PSCI, whereas increased adaptive immunity indicator (lymphocytes) were protective against PSCI, especially in patients aged 50-65 years. Neutrophil percentage and NLR improved the predictive efficacy of the models that included demographic, clinical, and imaging information, with the area under the curve increased from 0.765 to 0.804 and 0.803 (P = 0.042 and 0.049, respectively). We conducted a comprehensive analysis of peripheral immunity in PSCI, providing a novel perspective on the early detection, etiology, and treatment of PSCI.

Novel diagnostic and prognostic approach for rapidly progressive dementias: Indicators based on amyloid/tau/neurodegeneration (ATN) framework

AIMS

Apply established cerebrospinal fluid (CSF) and serum biomarkers and novel combined indicators based on the amyloid/tau/neurodegeneration (ATN) framework to improve diagnostic and prognostic power in patients with rapidly progressive dementias (RPDs).

METHODS

CSF and serum biomarkers of Alzheimer's disease (AD) common neuropathology including Aβ42, Aβ40, p-Tau, and t-Tau were measured in cognitively normal (CN) controls (n = 33) and three RPD groups with rapidly progressive AD (rpAD, n = 23), autoimmune encephalitis (AE, n = 25), and Creutzfeldt-Jakob disease (CJD, n = 28). Logistic regression and multiple linear regression were used for producing combined indicators and prognostic assessment, respectively, including A&T, A&N, T&N, A&T&N, etc. RESULTS: Combined diagnostic indicator with A&T&N had the potential for differentiating AE from other types of RPDs, identifying 62.51% and 75% of AE subjects based on CSF and serum samples, respectively, compared to 39.13% and 37.5% when using autoantibodies. CSF t-Tau was associated with survival in the CJD group (adjusted R-Square = 0.16, p = 0.02), and its prognosis value improved when using combined predictors based on the ATN framework (adjusted R-Square = 0.273, p = 0.014).

CONCLUSION

Combined indicators based on the ATN framework provide a novel perspective for establishing biomarkers for early recognition of RPDs due to treatment-responsive causes.

Cognitive functioning in patients with neuro-PASC: the role of fatigue, mood, and hospitalization status

This study sought to characterize cognitive functioning in patients with neurological post-acute sequelae of SARS-CoV-2 infection (Neuro-PASC) and investigate the association of subjective and objective functioning along with other relevant factors with prior hospitalization for COVID-19. Participants were 106 adult outpatients with Neuro-PASC referred for abbreviated neuropsychological assessment after scoring worse than one standard deviation below the mean on cognitive screening. Of these patients, 23 had been hospitalized and 83 had not been hospitalized for COVID-19. Subjective cognitive impairment was evaluated with the self-report cognition subscale from the Patient-Reported Outcome Measurement Information System. Objective cognitive performance was assessed using a composite score derived from multiple standardized cognitive measures. Other relevant factors, including fatigue and depression/mood symptoms, were assessed via the Patient-Reported Outcome Measurement Information System. Subjective cognitive impairment measures exceeded the minimal difficulties noted on objective tests and were associated with depression/mood symptoms as well as fatigue. However, fatigue independently explained the most variance (17.51%) in patients' subjective cognitive ratings. When adjusting for fatigue and time since onset of COVID-19 symptoms, neither objective nor subjective impairment were associated with prior hospitalization for COVID-19. Findings suggest that abbreviated neuropsychological assessment may not reveal objective difficulties beyond initial cognitive screening in patients with Neuro-PASC. However, subjective cognitive concerns may persist irrespective of hospitalization status, and are likely influenced by fatigue and depression/mood symptoms. The impact of concomitant management of fatigue and mood in patients with Neuro-PASC who report cognitive concerns deserve further study.

Meta-analysis of Cognitive Function Following Non-severe SARS-CoV-2 Infection

To effectively diagnose and treat subjective cognitive symptoms in post-acute sequalae of COVID-19 (PASC), it is important to understand objective cognitive impairment across the range of acute COVID-19 severity. Despite the importance of this area of research, to our knowledge, there are no current meta-analyses of objective cognitive functioning following non-severe initial SARS-CoV-2 infection. The aim of this meta-analysis is to describe objective cognitive impairment in individuals with non-severe (mild or moderate) SARS-CoV-2 cases in the post-acute stage of infection. This meta-analysis was pre-registered with Prospero (CRD42021293124) and utilized the PRISMA checklist for reporting guidelines, with screening conducted by at least two independent reviewers for all aspects of the screening and data extraction process. Fifty-nine articles (total participants = 22,060) with three types of study designs met our full criteria. Individuals with non-severe (mild/moderate) initial SARS-CoV-2 infection demonstrated worse objective cognitive performance compared to healthy comparison participants. However, those with mild (nonhospitalized) initial SARS-CoV-2 infections had better objective cognitive performance than those with moderate (hospitalized but not requiring ICU care) or severe (hospitalized with ICU care) initial SARS-CoV-2 infections. For studies that used normative data comparisons instead of healthy comparison participants, there was a small and nearly significant effect when compared to normative data. There were high levels of heterogeneity (88.6 to 97.3%), likely reflecting small sample sizes and variations in primary study methodology. Individuals who have recovered from non-severe cases of SARS-CoV-2 infections may be at risk for cognitive decline or impairment and may benefit from cognitive health interventions.

Long COVID in Brain Health Research: A Call to Action

The COVID-19 pandemic has brought attention to the long-term consequences of the virus, particularly the persistent symptoms that characterize long COVID. This syndrome, which can last for months after the initial infection, includes a range of neurological and neuropsychiatric manifestations that have significant implications for brain health and dementia research. This review explores the current understanding of long COVID's cognitive, neurological, and psychiatric symptoms and their potential impact on brain stimulation and neuroimaging studies. It argues that researchers must adapt their study designs and screening processes to account for the confounding effects of long COVID and ensure the accuracy and reliability of their findings. To advance the understanding of this condition and its long-term effects on brain health, the review proposes a series of strategies, including the development of standardized screening tools, the investigation of underlying mechanisms, and the identification of risk factors and protective factors. It also emphasizes the importance of collaborative research efforts and international data sharing platforms in accelerating the pace of discovery and developing targeted interventions for individuals with long COVID. As the prevalence of this condition continues to grow, it is imperative that the neuroscience community comes together to address this challenge and support those affected by long COVID.

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.

Computational Screening Using a Combination of Ligand-Based Machine Learning and Molecular Docking Methods for the Repurposing of Antivirals Targeting the SARS-CoV-2 Main Protease

BACKGROUND

COVID-19 is an infectious disease caused by SARS-CoV-2, a close relative of SARS-CoV. Several studies have searched for COVID-19 therapies. The topics of these works ranged from vaccine discovery to natural products targeting the SARS-CoV-2 main protease (Mpro), a potential therapeutic target due to its essential role in replication and conserved sequences. However, published research on this target is limited, presenting an opportunity for drug discovery and development.

METHOD

This study aims to repurpose 10692 drugs in DrugBank by using ligand-based virtual screening (LBVS) machine learning (ML) with Konstanz Information Miner (KNIME) to seek potential therapeutics based on Mpro inhibitors. The top candidate compounds, the native ligand (GC-376) of the Mpro inhibitor, and the positive control boceprevir were then subjected to absorption, distribution, metabolism, excretion, and toxicity (ADMET) characterization, drug-likeness prediction, and molecular docking (MD). Protein-protein interaction (PPI) network analysis was added to provide accurate information about the Mpro regulatory network.

RESULTS

This study identified 3,166 compound candidates inhibiting Mpro. The random forest (RF) molecular access system ML model provided the highest confidence score of 0.95 (bromo-7-nitroindazole) and identified the top 22 candidate compounds. Subjecting the 22 candidate compounds, the native ligand GC-376, and boceprevir to further ADMET property characterization and drug-likeness predictions revealed that one compound had two violations of Lipinski's rule. Additional MD results showed that only five compounds had more negative binding energies than the native ligand (- 12.25 kcal/mol). Among these compounds, CCX-140 exhibited the lowest score of - 13.64 kcal/mol. Through literature analysis, six compound classes with potential activity for Mpro were discovered. They included benzopyrazole, azole, pyrazolopyrimidine, carboxylic acids and derivatives, benzene and substituted derivatives, and diazine. Four pathologies were also discovered on the basis of the Mpro PPI network.

CONCLUSION

Results demonstrated the efficiency of LBVS combined with MD. This combined strategy provided positive evidence showing that the top screened drugs, including CCX-140, which had the lowest MD score, can be reasonably advanced to the in vitro phase. This combined method may accelerate the discovery of therapies for novel or orphan diseases from existing drugs.

Associations of hospital-treated infections with subsequent dementia: nationwide 30-year analysis

Infections, which can prompt neuroinflammation, may be a risk factor for dementia1-5. More information is needed concerning associations across different infections and different dementias, and from longitudinal studies with long follow-ups. This New Zealand-based population register study tested whether infections antedate dementia across three decades. We identified individuals born between 1929 and 1968 and followed them from 1989 to 2019 (n = 1,742,406, baseline age = 21-60 years). Infection diagnoses were ascertained from public hospital records. Dementia diagnoses were ascertained from public hospital, mortality and pharmaceutical records. Relative to individuals without an infection, those with an infection were at increased risk of dementia (hazard ratio 2.93, 95% confidence interval 2.68-3.20). Associations were evident for dementia diagnoses made up to 25-30 years after infection diagnoses. Associations held after accounting for preexisting physical diseases, mental disorders and socioeconomic deprivation. Associations were evident for viral, bacterial, parasitic and other infections, and for Alzheimer's disease and other dementias, including vascular dementia. Preventing infections might reduce the burden of neurodegenerative conditions.

RECOVER-NEURO: study protocol for a multi-center, multi-arm, phase 2, randomized, active comparator trial evaluating three interventions for cognitive dysfunction in post-acute sequelae of SARS-CoV-2 infection (PASC)

BACKGROUND

Post-acute sequelae of SARS-CoV-2 infection (PASC) symptoms have broad impact, and may affect individuals regardless of COVID-19 severity, socioeconomic status, race, ethnicity, or age. A prominent PASC symptom is cognitive dysfunction, colloquially referred to as "brain fog" and characterized by declines in short-term memory, attention, and concentration. Cognitive dysfunction can severely impair quality of life by impairing daily functional skills and preventing timely return to work.

METHODS

RECOVER-NEURO is a prospective, multi-center, multi-arm, phase 2, randomized, active-comparator design investigating 3 interventions: (1) BrainHQ is an interactive, online cognitive training program; (2) PASC-Cognitive Recovery is a cognitive rehabilitation program specifically designed to target frequently reported challenges among individuals with brain fog; (3) transcranial direct current stimulation (tDCS) is a noninvasive form of mild electrical brain stimulation. The interventions will be combined to establish 5 arms: (1) BrainHQ; (2) BrainHQ + PASC-Cognitive Recovery; (3) BrainHQ + tDCS-active; (4) BrainHQ + tDCS-sham; and (5) Active Comparator. The interventions will occur for 10 weeks. Assessments will be completed at baseline and at the end of intervention and will include cognitive testing and patient-reported surveys. All study activities can be delivered in Spanish and English.

DISCUSSION

This study is designed to test whether cognitive dysfunction symptoms can be alleviated by the use of pragmatic and established interventions with different mechanisms of action and with prior evidence of improving cognitive function in patients with neurocognitive disorder. If successful, results will provide beneficial treatments for PASC-related cognitive dysfunction.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05965739. Registered on July 25, 2023.

Blood brain barrier disruption and glutamatergic excitotoxicity in post-acute sequelae of SARS COV-2 infection cognitive impairment: potential biomarkers and a window into pathogenesis

Objective

To investigate the association between blood-brain barrier permeability, brain metabolites, microstructural integrity of the white matter, and cognitive impairment (CI) in post-acute sequelae of SARS-COV-2 infection (PASC).

Methods

In this multimodal longitudinal MRI study 14 PASC participants with CI and 10 healthy controls were enrolled. All completed investigations at 3 months following acute infection (3 months ± 2 weeks SD), and 10 PASC participants completed at 12 months ± 2.22 SD weeks. The assessments included a standard neurological assessment, a cognitive screen using the brief CogState battery and multi-modal MRI derived metrics from Dynamic contrast enhanced (DCE) perfusion Imaging, Diffusion Tensor Imaging (DTI), and single voxel proton Magnetic Resonance Spectroscopy. These measures were compared between patients and controls and correlated with cognitive scores.

Results

At baseline, and relative to controls, PASC participants had higher K-Trans and Myo-inositol, and lower levels of Glutamate/Glutamine in the frontal white matter (FWM) (p < 0.01) as well as in brain stem (p < 0.05), and higher FA and lower MD in the FWM (p < 0.05). In PASC participants, FA and MD decreased in the FWM at 12 months compared to baseline (p < 0.05). K-Trans and metabolite concentrations did not change significantly over time. Neurocognitive scores did not correlation with the increased permeability (K trans).

Interpretation

PASC with CI is associated with BBB impairment, loss of WM integrity, and inflammation at 3 months which significantly but not uniformly improved at 12 months. The loss of WM integrity is possibly mediated by BBB impairment and associated glutamatergic excitotoxicity.

Change in Neuropsychological Test Performance Seen in a Longitudinal Study of Patients With Post-acute Sequelae of COVID-19: A 6-Month Follow-up Study

BACKGROUND

Post-acute sequelae of COVID-19 may include physical, psychiatric, and neurocognitive symptoms. Few studies of cognitive symptoms have been longitudinal, with many following participants briefly after infection and relying on subjective complaints, screening instruments, or computerized testing. This group previously reported diminished neuropsychological (NP) test performance in over half of 60 individuals tested in-person 7 months post-COVID-19, particularly those seeking care for cognitive complaints. The current study describes the initial and 6-month follow-up results of an expanded cohort of 75 participants.

OBJECTIVE

To measure longitudinal changes in neuropsychological test performance, as well as medical and psychiatric changes, post-COVID-19.

METHODS

Participants underwent NP, psychiatric, and medical assessments approximately 7 months after acute COVID-19 infection. Sixty-three (84%) returned approximately 6 months later for repeat evaluation.

RESULTS

At the initial visit, 29 (38.7%) met criteria for low NP performance, and 16 (21.3%) met criteria for extremely low NP performance. At 6-month follow-up, several NP domains that were significantly below normative values at the initial visit were no longer abnormal, with the exception of language. Only measures of delayed memory and fatigue showed significant improvements between the 2 time points.

CONCLUSIONS

A substantial proportion of individuals recovered from acute COVID-19 infection have persistent neuropsychiatric symptoms over 1 year after infection. While the overall sample in this study showed some improvement in NP test performance relative to norms, only fatigue and delayed memory improved significantly between times 1 and 2. No individual declined in NP test performance, though relatively few individuals made significant clinical improvement, indicating the need for serial neuropsychiatric assessment and treatment supports. Longitudinal follow-up of this cohort is in progress.

Neurocognitive Impairment in Post-COVID-19 Condition in Adults: Narrative Review of the Current Literature

The severe acute respiratory syndrome coronavirus 2 virus has, up to the time of this article, resulted in >770 million cases of COVID-19 illness worldwide, and approximately 7 million deaths, including >1.1 million in the United States. Although defined as a respiratory virus, early in the pandemic, it became apparent that considerable numbers of people recovering from COVID-19 illness experienced persistence or new onset of multi-system health problems, including neurologic and cognitive and behavioral health concerns. Persistent multi-system health problems are defined as Post-COVID-19 Condition (PCC), Post-Acute Sequelae of COVID-19, or Long COVID. A significant number of those with PCC report cognitive problems. This paper reviews the current state of scientific knowledge on persisting cognitive symptoms in adults following COVID-19 illness. A brief history is provided of the emergence of concerns about persisting cognitive problems following COVID-19 illness and the definition of PCC. Methodologic factors that complicate clear understanding of PCC are reviewed. The review then examines research on patterns of cognitive impairment that have been found, factors that may contribute to increased risk, behavioral health variables, and interventions being used to ameliorate persisting symptoms. Finally, recommendations are made about ways neuropsychologists can improve the quality of existing research.

Cognitive Impairment in the Post-Acute Phases of COVID-19 and Mechanisms: An Introduction and Narrative Review

Cognitive impairment is a primary manifestation of neurological symptoms associated with COVID-19 and may occur after disease resolution. Although cognitive impairment has been extensively reported in the literature, its duration and rate of remission remain controversial. This study discusses the various factors that influence cognitive impairment, including demographic characteristics, genetics, as well as disease course and severity. Furthermore, imaging and laboratory data have suggested various associations with cognitive impairment, most notably changes in EEG patterns, PET imaging, and serum markers. Some findings suggest similarities and potential links between COVID-related cognitive impairment and Alzheimer's disease. Moreover, this study reviews the various mechanisms proposed to explain the development of cognitive impairment in COVID-19, including cytokine storm, damage to the blood-brain barrier, compromise of small vessel integrity, hypoxic conditions, and immune dysregulation.

Understanding Patient-Reported Outcome Measures Used in Adult Survivors Experiencing Long-Term Effects After COVID-19 Infection: A Rapid Review

Purpose

Patient-reported outcome measures (PROMs) are used in individuals experiencing long-term effects from COVID-19 infection, or Long COVID, to evaluate the quality of life and functional status of these individuals. However, little is known about which PROMs are being utilised and the psychometric properties of these PROMs. Our purpose was thus to explore which PROMs are used in Long COVID patients and to discuss the psychometric properties of the PROMs.

Methods

For this rapid review, a systematic literature search was performed in the PubMed, Embase, and CINAHL databases. The found studies were screened using the PRISMA flowchart. We then performed study quality appraisal and assessed the psychometric properties of the found PROMs.

Results

Per the systematic literature search and after removal of duplicates, 157 publications were identified for individual screening. After screening and eligibility assessment, 74 articles were selected for our review. In total, 74 PROMs were used and primarily comprised quality of life, fatigue, breathlessness, mental health, and smell/taste issues in COVID "long haulers." Five studies used newly developed, COVID-19-specific PROMs. We assessed the psychometric properties of the 10 most-used PROMs. The majority were found to be reliable and valid instruments. EQ-5D-5L was the most popular and highly rated PROM.

Conclusions

We assessed PROMs used in Long COVID patients and evaluated their psychometric properties. EQ-5D-5L was the most favourably rated PROM. PROMs addressing mental health issues are crucial in managing anxiety and depression in Long COVID patients. New COVID-specific PROMs assess functional status and smell/taste perception and show great utilisation potential in olfactory training at COVID smell clinics. However, many reviewed PROMs currently lack sufficient analysis of their psychometric properties. Therefore, future research needs to examine these measures.

Update on modifiable risk factors for Alzheimer's disease and related dementias

PURPOSE OF REVIEW

All human beings undergo a lifelong cumulative exposure to potentially preventable adverse factors such as toxins, infections, traumatisms, and cardiovascular risk factors, collectively termed exposome. The interplay between the individual's genetics and exposome is thought to have a large impact in health outcomes such as cancer and cardiovascular disease. Likewise, a growing body of evidence is supporting the idea that preventable factors explain a sizable proportion of Alzheimer's disease and related dementia (ADRD) cases.

RECENT FINDINGS

Here, we will review the most recent epidemiological, experimental preclinical, and interventional clinical studies examining some of these potentially modifiable risk factors for ADRD. We will focus on new evidence regarding cardiovascular risk factors, air pollution, viral and other infectious agents, traumatic brain injury, and hearing loss.

SUMMARY

While greater and higher quality epidemiological and experimental evidence is needed to unequivocally confirm their causal link with ADRD and/or unravel the underlying mechanisms, these modifiable risk factors may represent a window of opportunity to reduce ADRD incidence and prevalence at the population level via health screenings, and education and health policies.

Alterations in microbiota of patients with COVID-19: implications for therapeutic interventions

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) recently caused a global pandemic, resulting in more than 702 million people being infected and over 6.9 million deaths. Patients with coronavirus disease (COVID-19) may suffer from diarrhea, sleep disorders, depression, and even cognitive impairment, which is associated with long COVID during recovery. However, there remains no consensus on effective treatment methods. Studies have found that patients with COVID-19 have alterations in microbiota and their metabolites, particularly in the gut, which may be involved in the regulation of immune responses. Consumption of probiotics may alleviate the discomfort caused by inflammation and oxidative stress. However, the pathophysiological process underlying the alleviation of COVID-19-related symptoms and complications by targeting the microbiota remains unclear. In the current study, we summarize the latest research and evidence on the COVID-19 pandemic, together with symptoms of SARS-CoV-2 and vaccine use, with a focus on the relationship between microbiota alterations and COVID-19-related symptoms and vaccine use. This work provides evidence that probiotic-based interventions may improve COVID-19 symptoms by regulating gut microbiota and systemic immunity. Probiotics may also be used as adjuvants to improve vaccine efficacy.

COVID-19 and Alzheimer's disease: Impact of lockdown and other restrictive measures during the COVID-19 pandemic

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection initially results in respiratory distress symptoms but can also lead to central nervous system (CNS) and neurological manifestations, significantly impacting coronavirus disease 2019 (COVID-19) patients with neurodegenerative diseases. Additionally, strict lockdown measures introduced to curtail the spread of COVID-19 have raised concerns over the wellbeing of patients with dementia and/or Alzheimer's disease. The aim of this review was to discuss the overlapping molecular pathologies and the potential bidirectional relationship between COVID-19 and Alzheimer's dementia, as well as the impact of lockdown/restriction measures on the neuropsychiatric symptoms (NPS) of patients with Alzheimer's dementia. Furthermore, we aimed to assess the impact of lockdown measures on the NPS of caregivers, exploring its potential effects on the quality and extent of care they provide to dementia patients.We utilized the PubMed and Google Scholar databases to search for articles on COVID-19, dementia, Alzheimer's disease, lockdown, and caregivers. Our review highlights that patients with Alzheimer's disease face an increased risk of COVID-19 infection and complications. Additionally, these patients are likely to experience greater cognitive decline. It appears that these issues are primarily caused by the SARS-CoV-2 infection and appear to be further exacerbated by restrictive/lockdown measures. Moreover, lockdown measures introduced during the pandemic have negatively impacted both the NPSs of caregivers and their perception of the wellbeing of their Alzheimer's patients. Thus, additional safeguard measures, along with pharmacological and non-pharmacological approaches, are needed to protect the wellbeing of dementia patients and their caregivers in light of this and possible future pandemics.