Acute TNFα levels predict cognitive impairment 6-9 months after COVID-19 infection

Cognitive profile, neuroimaging and fluid biomarkers in post-acute COVID-19 syndrome

We aimed to characterize the cognitive profile of post-acute COVID-19 syndrome (PACS) patients with cognitive complaints, exploring the influence of biological and psychological factors. Participants with confirmed SARS-CoV-2 infection and cognitive complaints ≥ 8 weeks post-acute phase were included. A comprehensive neuropsychological battery (NPS) and health questionnaires were administered at inclusion and at 1, 3 and 6 months. Blood samples were collected at each visit, MRI scan at baseline and at 6 months, and, optionally, cerebrospinal fluid. Cognitive features were analyzed in relation to clinical, neuroimaging, and biochemical markers at inclusion and follow-up. Forty-nine participants, with a mean time from symptom onset of 10.4 months, showed attention-executive function (69%) and verbal memory (39%) impairment. Apathy (64%), moderate-severe anxiety (57%), and severe fatigue (35%) were prevalent. Visual memory (8%) correlated with total gray matter (GM) and subcortical GM volume. Neuronal damage and inflammation markers were within normal limits. Over time, cognitive test scores, depression, apathy, anxiety scores, MRI indexes, and fluid biomarkers remained stable, although fewer participants (50% vs. 75.5%; p = 0.012) exhibited abnormal cognitive evaluations at follow-up. Altered attention/executive and verbal memory, common in PACS, persisted in most subjects without association with structural abnormalities, elevated cytokines, or neuronal damage markers.

Persistence and emergence of new neuropsychological deficits following SARS-CoV-2 infection: A follow-up assessment of the Geneva COVID-COG cohort

Background

Despite numerous observations of neuropsychological deficits immediately following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, little is known about what happens to these deficits over time and whether they are affected by changes in fatigue and any psychiatric symptoms. We aimed to assess the prevalence of neuropsychological deficits at 6-9 months and again at 12-15 months after coronavirus disease 2019 (COVID-19) and to explore whether it was associated with changes in fatigue and psychiatric symptoms.

Methods

We administered a series of neuropsychological tests and psychiatric questionnaires to 95 patients (mean age = 57.12 years, standard deviation (SD) = 10.68; 35.79% women) 222 (time point 1 (T1)) and 441 (time point 2 (T2)) days on average after infection. Patients were categorised according to the severity of their respiratory COVID-19 symptoms in the acute phase: mild (no hospitalisation), moderate (conventional hospitalisation), and severe (hospitalisation in intensive care unit (ICU) plus mechanical ventilation). We ran Monte-Carlo simulation methods at each time point to generate a simulated population and then compared the cumulative percentages of cognitive disorders displayed by the three patient subgroups with the estimated normative data. We calculated generalised estimating equations for the whole sample to assess the longitudinal associations between cumulative neuropsychological deficits, fatigue, and psychiatric data (anxiety, depressive symptoms, posttraumatic stress disorder, and apathy).

Results

Most participants (>50%) exhibited a decrease in their neuropsychological impairments, while approximately 25% showed an escalation in these cognitive deficits. At T2, patients in the mild subgroup remained free of accumulated neuropsychological impairments. Patients with moderate severity of symptoms displayed a decrease in the magnitude of cumulative deficits in perceptual and attentional functions, a persistence of executive, memory and logical reasoning deficits, and the emergence of language deficits. In patients with severe symptoms, perceptual deficits emerged and executive deficits increased, while attentional and memory deficits remained unchanged. Changes in executive functions were significantly associated with changes in depressive symptoms, but the generalised estimating equations failed to reveal any other significant effect.

Conclusion

While most cumulative neuropsychological deficits observed at T1 persisted and even worsened over time in the subgroups of patients with moderate and severe symptoms, a significant proportion of patients, mainly in the mild subgroup, exhibited improved performances. However, we identified heterogeneous neuropsychological profiles both cross-sectionally and over time, suggesting that there may be distinct patient phenotypes. Predictors of these detrimental dynamics have yet to be identified.

Long COVID, the Brain, Nerves, and Cognitive Function

SARS-CoV-2, a single-stranded RNA coronavirus, causes an illness known as coronavirus disease 2019 (COVID-19). Long-term complications are an increasing issue in patients who have been infected with COVID-19 and may be a result of viral-associated systemic and central nervous system inflammation or may arise from a virus-induced hypercoagulable state. COVID-19 may incite changes in brain function with a wide range of lingering symptoms. Patients often experience fatigue and may note brain fog, sensorimotor symptoms, and sleep disturbances. Prolonged neurological and neuropsychiatric symptoms are prevalent and can interfere substantially in everyday life, leading to a massive public health concern. The mechanistic pathways by which SARS-CoV-2 infection causes neurological sequelae are an important subject of ongoing research. Inflammation- induced blood-brain barrier permeability or viral neuro-invasion and direct nerve damage may be involved. Though the mechanisms are uncertain, the resulting symptoms have been documented from numerous patient reports and studies. This review examines the constellation and spectrum of nervous system symptoms seen in long COVID and incorporates information on the prevalence of these symptoms, contributing factors, and typical course. Although treatment options are generally lacking, potential therapeutic approaches for alleviating symptoms and improving quality of life are explored.