Studying the neuropsychological sequelae of SARS-CoV-2: lessons learned from 35 years of neuroHIV research

HIV and COVID-19: two pandemics with significant (but different) central nervous system complications

Human immunodeficiency virus (HIV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) cause significant neurologic disease. Central nervous system (CNS) involvement of HIV has been extensively studied, with well-documented invasion of HIV into the brain in the initial stage of infection, while the acute effects of SARS-CoV-2 in the brain are unclear. Neuropathologic features of active HIV infection in the brain are well characterized whereas neuropathologic findings in acute COVID-19 are largely non-specific. On the other hand, neuropathologic substrates of chronic dysfunction in both infections, as HIV-associated neurocognitive disorders (HAND) and post-COVID conditions (PCC)/long COVID are unknown. Thus far, neuropathologic studies on patients with HAND in the era of combined antiretroviral therapy have been inconclusive, and autopsy studies on patients diagnosed with PCC have yet to be published. Further longitudinal, multidisciplinary studies on patients with HAND and PCC and neuropathologic studies in comparison to controls are warranted to help elucidate the mechanisms of CNS dysfunction in both conditions.

The Impact of COVID-19 on People Living with HIV-1 and HIV-1-Associated Neurological Complications

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is the causative pathogen of the coronavirus disease 2019 (COVID-19) pandemic, a fatal respiratory illness. The associated risk factors for COVID-19 are old age and medical comorbidities. In the current combined antiretroviral therapy (cART) era, a significant portion of people living with HIV-1 (PLWH) with controlled viremia is older and with comorbidities, making these people vulnerable to SARS-CoV-2 infection and COVID-19-associated severe outcomes. Additionally, SARS-CoV-2 is neurotropic and causes neurological complications, resulting in a health burden and an adverse impact on PLWH and exacerbating HIV-1-associated neurocognitive disorder (HAND). The impact of SARS-CoV-2 infection and COVID-19 severity on neuroinflammation, the development of HAND and preexisting HAND is poorly explored. In the present review, we compiled the current knowledge of differences and similarities between SARS-CoV-2 and HIV-1, the conditions of the SARS-CoV-2/COVID-19 and HIV-1/AIDS syndemic and their impact on the central nervous system (CNS). Risk factors of COVID-19 on PLWH and neurological manifestations, inflammatory mechanisms leading to the neurological syndrome, the development of HAND, and its influence on preexisting HAND are also discussed. Finally, we have reviewed the challenges of the present syndemic on the world population, with a particular emphasis on PLWH.

Rehabilitation of Neuropsychiatric Symptoms in Patients With Long COVID: Position Statement

Long COVID, a term used to describe ongoing symptoms after COVID-19 infection, parallels the course of other postviral syndromes. Neuropsychiatric symptoms of long COVID can be persistent and interfere with quality of life and functioning. Within the biopsychosocial framework of chronic illness, rehabilitation professionals can address the neuropsychiatric sequelae of long COVID. However, current practice models are not designed to address concurrent psychiatric and cognitive symptoms in adults living with long COVID. Thus, we present a biopsychosocial framework for long COVID and provide treatment strategies based on evidence from current literature of postviral chronic illness. These recommendations will guide rehabilitation professionals in identifying common neuropsychiatric symptoms in long COVID that can be targeted for intervention and addressing these symptoms via integrative interventions taking into account the biopsychosocial presentation of long COVID symptoms.

Assessment and Diagnosis of HIV-Associated Dementia

The modern combined antiretroviral treatment (cART) for human immunodeficiency virus (HIV) infection has substantially lowered the incidence of HIV-associated dementia (HAD). The dominant clinical features include deficits in cognitive processing speed, concentration, attention, and memory. As people living with HIV become older, with high rates of comorbidities and concomitant treatments, the prevalence and complexity of cognitive impairment are expected to increase. Currently, the management of HAD and milder forms of HAND is grounded on the best clinical practice, as there is no specific, evidence-based, proven intervention for managing cognitive impairment. The present article acknowledges the multifactorial nature of the cognitive impairments found in HIV patients, outlining the current concepts in the field of HAD. Major areas of interest include neuropsychological testing and neuroimaging to evaluate CNS status, focusing on greater reliability in the exclusion of associated diseases and allowing for earlier diagnosis. Additionally, we considered the evidence for neurological involvement in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and the impact of the coronavirus (COVID-19) pandemic, with wider consequences to population health than can be attributed to the virus itself. The indirect effects of COVID-19, including the increased adoption of telehealth, decreased access to community resources, and social isolation, represent a significant health burden, disproportionately affecting older adults with dementia who have limited social networks and increased functional dependence on the community and health system. This synopsis reviews these aspects in greater detail, identifying key gaps and opportunities for researchers and clinicians; we provide an overview of the current concepts in the field of HAD, with suggestions for diagnosing and managing this important neurological complication, which is intended to be applicable across diverse populations, in line with clinical observations, and closely representative of HIV brain pathology.

Assessment of Neurocognitive Functions, Olfaction, Taste, Mental, and Psychosocial Health in COVID-19 in Adults: Recommendations for Harmonization of Research and Implications for Clinical Practice

OBJECTIVE

To propose a set of internationally harmonized procedures and methods for assessing neurocognitive functions, smell, taste, mental, and psychosocial health, and other factors in adults formally diagnosed with COVID-19 (confirmed as SARS-CoV-2 + WHO definition).

METHODS

We formed an international and cross-disciplinary NeuroCOVID Neuropsychology Taskforce in April 2020. Seven criteria were used to guide the selection of the recommendations' methods and procedures: (i) Relevance to all COVID-19 illness stages and longitudinal study design; (ii) Standard, cross-culturally valid or widely available instruments; (iii) Coverage of both direct and indirect causes of COVID-19-associated neurological and psychiatric symptoms; (iv) Control of factors specifically pertinent to COVID-19 that may affect neuropsychological performance; (v) Flexibility of administration (telehealth, computerized, remote/online, face to face); (vi) Harmonization for facilitating international research; (vii) Ease of translation to clinical practice.

RESULTS

The three proposed levels of harmonization include a screening strategy with telehealth option, a medium-size computerized assessment with an online/remote option, and a comprehensive evaluation with flexible administration. The context in which each harmonization level might be used is described. Issues of assessment timelines, guidance for home/remote assessment to support data fidelity and telehealth considerations, cross-cultural adequacy, norms, and impairment definitions are also described.

CONCLUSIONS

The proposed recommendations provide rationale and methodological guidance for neuropsychological research studies and clinical assessment in adults with COVID-19. We expect that the use of the recommendations will facilitate data harmonization and global research. Research implementing the recommendations will be crucial to determine their acceptability, usability, and validity.

Acute to Chronic Electro-Clinical Manifestations of Neuro-COVID and the Long-Haul Consequences in People With Epilepsy: A Review

Severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) infection can involve the central nervous system (CNS). Acute symptomatic seizures or epileptiform discharges have not been commonly reported in patients with altered mental status related to coronavirus disease 2019 (COVID-19) infection. However, long-term neurological symptoms have been reported after COVID-19 infection (i.e., brain fog, cognitive complaints, and confusion), suggesting chronic encephalopathy. People with epilepsy (PWE) have been specifically affected by the COVID-19 pandemic, with changes in their seizure frequency, quality of life, health care accessibility, and medication interactions. This narrative review highlights possible pathophysiological mechanisms of COVID-19 on the brain, related to short- and long-term epileptiform activity and the impact of this infection on PWE.

Long-Acting Protective Ocular Surface by Instilling Adhesive Dual-Antiviral Nanoparticles

The eye is susceptible to viral infections, causing severe ocular symptoms or even respiratory diseases. Methods capable of protecting the eye from external viral invasion in a long-term and highly effective way are urgently needed but have been proved to be extremely challenging. Here, a strategy of forming a long-acting protective ocular surface is described by instilling adhesive dual-antiviral nanoparticles. Taking pseudotyped severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as a model virus, antiviral agent-loaded nanoparticles are coated with a "double-lock" hybrid cell membrane abundant with integrin-β1 and angiotensin converting enzyme II (ACE2). After instillation, the presence of integrin-β1 endows coated nanoparticles with steady adhesion via specific binding to Arg-Gly-Asp sequence on the fibronectin of ocular epithelium, achieving durable retention on the ocular surface. In addition to loaded inhibitors, the exposure of ACE2 can trap SARS-CoV-2 and subsequently neutralize the associated spike protein, playing a dual antiviral effect of the resulting nanoparticles. Adhesive dual-antiviral nanoparticles enabled by coating with a "double-lock" hybrid cell membrane could be a versatile platform for topical long-acting protection against viral infection of the eye.

Association of depression and COVID-induced PTSD with cognitive symptoms after COVID-19 illness

OBJECTIVE

Many patients recovering from COVID-19 report persistent psychological and cognitive symptoms months after viral clearance. We examined the association of depression and COVID-induced PTSD with cognitive symptoms following COVID-19 illness.

METHODS

Patients treated for COVID-19 between March 26 and May 27, 2020 were surveyed three months later. Cognitive symptoms were assessed by asking "Since your COVID-19 illness, do you now have more difficulty: 1) Remembering conversations a few days later? 2) Remembering where you placed familiar objects? 3) Finding the right words while speaking?" Patients endorsing at least one such complaint were coded positive for cognitive symptoms. Logistic regression was used to estimate the association of depression (PHQ-8 ≥ 10) and COVID-induced PTSD (PCL-5 ≥ 30) with cognitive symptoms, adjusting for demographic and clinical factors.

RESULTS

Among 153 participants, 44.4% reported at least one cognitive symptom, 18.3% were depressed, and 23.5% had COVID-induced PTSD. Adjusting for covariates, depression (OR 5.15, 95% CI 1.30-20.35, p = 0.02) and COVID-induced PTSD (OR 3.67, 95% CI 1.13-11.89, p = 0.03) were significantly associated with cognitive symptoms; self-reported history of mental illness was also associated (OR 4.90, 95% CI 1.24-19.41, p = 0.02).

CONCLUSIONS

Depression, COVID-induced PTSD, and prior mental illness were strongly associated with cognitive symptoms three months after acute COVID-19 illness.

HIV, HSV, SARS-CoV-2 and Ebola Share Long-Term Neuropsychiatric Sequelae

Long COVID, in which disease-related symptoms persist for months after recovery, has led to a revival of the discussion of whether neuropsychiatric long-term symptoms after viral infections indeed result from virulent activity or are purely psychological phenomena. In this review, we demonstrate that, despite showing differences in structure and targeting, many viruses have highly similar neuropsychiatric effects on the host. Herein, we compare severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), human immunodeficiency virus 1 (HIV-1), Ebola virus disease (EVD), and herpes simplex virus 1 (HSV-1). We provide evidence that the mutual symptoms of acute and long-term anxiety, depression and post-traumatic stress among these viral infections are likely to result from primary viral activity, thus suggesting that these viruses share neuroinvasive strategies in common. Moreover, it appears that secondary induced environmental stress can lead to the emergence of psychopathologies and increased susceptibility to viral (re)infection in infected individuals. We hypothesize that a positive feedback loop of virus-environment-reinforced systemic responses exists. It is surmised that this cycle of primary virulent activity and secondary stress-induced reactivation, may be detrimental to infected individuals by maintaining and reinforcing the host's immunocompromised state of chronic inflammation, immunological strain, and maladaptive central-nervous-system activity. We propose that this state can lead to perturbed cognitive processing and promote aversive learning, which may manifest as acute, long-term neuropsychiatric illness.

Nervous System-Systemic Crosstalk in SARS-CoV-2/COVID-19: A Unique Dyshomeostasis Syndrome

SARS-CoV-2 infection is associated with a spectrum of acute neurological syndromes. A subset of these syndromes promotes higher in-hospital mortality than is predicted by traditional parameters defining critical care illness. This suggests that deregulation of components of the central and peripheral nervous systems compromises the interplay with systemic cellular, tissue and organ interfaces to mediate numerous atypical manifestations of COVID-19 through impairments in organismal homeostasis. This unique dyshomeostasis syndrome involves components of the ACE-2/1 lifecycles, renin-angiotensin system regulatory axes, integrated nervous system functional interactions and brain regions differentially sculpted by accelerated evolutionary processes and more primordial homeostatic functions. These biological contingencies suggest a mechanistic blueprint to define long-term neurological sequelae and systemic manifestations such as premature aging phenotypes, including organ fibrosis, tissue degeneration and cancer. Therapeutic initiatives must therefore encompass innovative combinatorial agents, including repurposing FDA-approved drugs targeting components of the autonomic nervous system and recently identified products of SARS-CoV-2-host interactions.

Neuropsychological Pattern in a Series of Post-Acute COVID-19 Patients in a Rehabilitation Unit: Retrospective Analysis and Correlation with Functional Outcomes

Intensive Care Unit delirium, insomnia, anxiety, and frontal/dysexecutive disorders have been described following COVID-19 infection. The aim of this case study was to re-evaluate the neuropsychological pattern in a series of patients with COVID-19 outcomes. We retrospectively evaluated 294 patients admitted to the Istituti Clinici Scientifici Maugeri of Lumezzane (Brescia) (May-September 2020). Neuropsychological assessment was available for 12 patients. We extracted clinical, functional data (FIM and Barthel Index score) and neuropsychological tests (MMSE, Trail making a-b, verbal fluency test, digit span, prose memory test, Frontal Assessment Battery, clock drawing test, Rey-Osterrieth complex figure, Tower of London test). The results were analyzed by Spearman (rho) correlation. Six patients presented dysexecutive alterations even in the presence of normal overall cognitive functioning. Forward digit span score was directly correlated to FIM value at admission (p = 0.015) and inversely correlated to delta FIM (p = 0.030) and delta Barthel Index (p = 0.025). In our experience, subclinical cognitive alterations were present in 4% of patients recovering from COVID-19 pneumonia. The possible correlation between verbal memory and frontal functions, and the degree of functional impairment at admission and its subsequent improvement, underscores the importance of an adequate cognitive evaluation and rehabilitation.

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

Objective: To date, very few studies investigating neurocognitive deficits in COVID-19 have been published. This case series addresses cognition in post-COVID-19 patient by describing three patients in acute rehabilitation to inform a model of cognitive sequelae of COVID-19. Methods: Three English-speaking inpatients with severe symptoms and long-term intensive care unit (ICU) treatment are described. All patients had a premorbid history of hypertension and hyperlipidemia and experienced delirium and hypoxemia when hospitalized. Patient 1 is a 62-year-old male with 15 years of education with additional history of obstructive sleep apnea and type 2 diabetes. Patient 2 is a 73-year-old female with 12 years of education with a premorbid medical history of alcohol use disorder and Guillain-Barre syndrome. Patient 3 is a 75-year-old male with 14 years of education. No patients had premorbid psychiatric histories. Results: The three patients demonstrated deficits on formal neuropsychological testing, particularly with encoding and verbal fluency. Memory measures improved with a more structured story memory task compared to a less-structured verbal list-learning task, suggesting executive dysfunction impacted learning. None of the patients demonstrated rapid forgetting of information. Two patients endorsed new depressive and/or anxiety symptoms. Conclusions: The results suggest evidence for neurocognitive deficits after severe COVID-19 infection, particularly in encoding and verbal fluency. These results were interpreted with caution given the limited number of patients and the telephone-based battery. The specific mechanism that caused these cognitive deficits in these individuals remains unclear. A proposed three-stage model of cognitive dysfunction is described to help guide future research.