Evaluation of cognitive, mental, and sleep patterns of post-acute COVID-19 patients and their correlation with thorax CT

Intervention modalities for brain fog caused by long-COVID: systematic review of the literature

Individuals suffering from long-COVID can present with "brain fog", which is characterized by a range of cognitive impairments, such as confusion, short-term memory loss, and difficulty concentrating. To date, several potential interventions for brain fog have been considered. Notably, no systematic review has comprehensively discussed the impact of each intervention type on brain fog symptoms. We included studies on adult (aged > 18 years) individuals with proven long- COVID brain-fog symptoms from PubMed, MEDLINE, Central, Scopus, and Embase. A search limit was set for articles published between 01/2020 and 31/12/2023. We excluded studies lacking an objective assessment of brain fog symptoms and patients with preexisting neurological diseases that affected cognition before COVID-19 infection. This review provided relevant information from 17 studies. The rehabilitation studies utilized diverse approaches, leading to a range of outcomes in terms of the effectiveness of the interventions. Six studies described noninvasive brain stimulation, and all showed improvement in cognitive ability. Three studies described hyperbaric oxygen therapy, all of which showed improvements in cognitive assessment tests and brain perfusion. Two studies showed that the use of Palmitoylethanolamide and Luteolin (PEA-LUT) improved cognitive impairment. Noninvasive brain stimulation and hyperbaric oxygen therapy showed promising results in the treatment of brain fog symptoms caused by long-COVID, with improved perfusion and cortical excitability. Furthermore, both rehabilitation strategies and PEA-LUT administration have been associated with improvements in symptoms of brain fog. Future studies should explore combinations of interventions and include longer follow-up periods to assess the long-term effects of these treatments.

Poor sleep quality may trigger cognitive deficits after recovery from COVID-19

Objective

In the present study, we aimed to assess the cognition of post-COVID-19 condition (PCC) participants in relation to their subjective sleep quality (Pittsburgh Sleep Quality Index, PSQI) and to analyse possible moderators of this effect, such as quality of life (European Quality of Life-5 Dimensions, EQ-5D), fatigue (Chadler Fatigue Questionnaire, CFQ), cognitive reserve (Cognitive Reserve Questionnaire, CRC), and subjective cognitive complaints (Memory Failures of Everyday Questionnaire, MFE-30).

Methods

We included 373 individuals with PCC and 126 healthy controls (HCs) from the NAUTILUS Project (NCT05307549 and NCT05307575) who were assessed with a comprehensive neuropsychological battery and various questionnaires.

Results

We found that PCC participants with poor sleep quality had a 4.3% greater risk of immediate verbal memory deficits than those with good sleep quality, as indicated by the greater odds ratio (OR) of 1.043 and confidence interval (CI) of 1.023-1.063. Additionally, their risk of immediate verbal memory disorders was multiplied by 2.4 when their EQ-5D score was low (OR 0.33; CI 0.145-0.748), and they had a lower risk of delayed visual memory deficits with a greater CRC (OR 0.963; CI 0.929-0.999). With respect to processing speed, PCC participants with poor sleep quality had a 6.7% greater risk of deficits as the MFE increased (OR 1.059; CI 1.024-1.096), and the risk of slowed processing speed tripled with a lower EQ-5D (OR 0.021; CI 0.003-0.141).

Conclusion

These results indicate that poor subjective sleep quality is a potential trigger for cognitive deficits. Therapeutic strategies to maximize sleep quality could include reducing sleep disturbances and perhaps cognitive impairment in PCC individuals.

The Impact of Long COVID on Cognitive Performance and Sleep Quality: An Analysis of the Rancagua Chilean Study (RACHIS)

Background Infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can lead to prolonged symptoms post-recovery, commonly known as long-term coronavirus disease 2019 (COVID-19) or "long COVID." Neuropsychiatric consequences of long COVID include cognitive dysfunction and sleep disturbances, which significantly impair daily living. This study aimed to explore the impact of long COVID on cognitive performance and sleep quality in patients receiving outpatient care. Material and methods This study involved a random sample of 138 of 363 patients, corresponding to 38% of the cohort, who tested positive for SARS-CoV-2 via polymerase chain reaction (PCR) between May 2020 and April 2021. These unvaccinated, non-hospitalized individuals, predominantly exhibiting mild disease symptoms, were prospectively assessed 11 months post-positive PCR test. After informed consent, demographic data, memory, and concentration impairment levels were collected through interviews. Participants reporting cognitive symptoms underwent the Mini-Mental State Examination (MMSE), the Montreal Cognitive Assessment (MOCA), and the Pittsburgh Sleep Quality Index. Statistical analyses were conducted, including Student's t-test, Chi-square, Fisher's test, Kruskal-Wallis test, and Pearson correlation coefficient, with a significance threshold set at p<0.05. Results Of the 138 participants, 76 (55.1%) were female and 62 (44.9%) were male. The mean age was 45.9 years (± 13.0), with an average educational attainment of 10.4 years (± 3.7). Roughly 50% of the patients reported significant memory and concentration issues (p<0.001). Thirty-three participants underwent detailed cognitive assessments, revealing a 2:1 female-to-male ratio and a significantly higher prevalence of depression in female participants. Cognitive deficits were diagnosed in five (15.2%) participants via the MMSE and in 26 (78.8%) via the MOCA test, with notable deficits in visuospatial/executive functions, language repeat, and deferred recall (p<0.001). A lower educational level was correlated with higher cognitive deficits (p=0.03). Conclusion The study findings reveal that cognitive impairments, as a consequence of COVID-19, can persist up to 11 months post-infection. The MOCA test proved more effective in diagnosing these deficits and requires adjustments based on educational background. Sleep parameters remained largely unaffected in this cohort, likely attributed to the mild nature of the initial symptoms and the outpatient management of the disease.

Aftereffects in Epigenetic Age Related to Cognitive Decline and Inflammatory Markers in Healthcare Personnel with Post-COVID-19: A Cross-Sectional Study

Purpose

Epigenetic age and inflammatory markers have been proposed as indicators of severity and mortality in patients with COVID-19. Furthermore, they have been associated with the occurrence of neurological symptoms, psychiatric manifestations, and cognitive impairment. Therefore, we aimed to explore the possible associations between epigenetic age, neuropsychiatric manifestations and inflammatory markers (neutrophil-lymphocyte ratio [NLR], platelet-lymphocyte ratio [PLR], monocyte-lymphocyte ratio [MLR], and systemic immune-inflammation index [SII]) in healthcare personnel with post-COVID condition.

Patients and Methods

We applied the Montreal Cognitive Assessment (MoCA) and Mini-Mental State Examination (MMSE) tests to 51 Mexican healthcare workers with post-COVID-19 condition; we also estimated their epigenetic age using the PhenoAge calculator.

Results

The participants had a post-COVID condition that lasted a median of 14 months (range: 1-20). High NLR (>1.73) had association with mild cognitive impairment by MMSE (p=0.013). Likewise, high MLR (>0.24) were associated with language domain in MOCA (p=0.046). Low PLR (<103.9) was also related to delayed recall in MOCA (p=0.040). Regarding comorbidities, hypertension was associated with SII (p=0.007), overweight with PLR (p=0.047) and alcoholism was associated with MLR (p=0.043). Interestingly, we observed associations of low PLR (<103.9) and low SII (<1.35) levels with increased duration of post-COVID condition (p=0.027, p=0.031). Likewise, increases in PhenoAge were associated with high levels of SII (OR=1.11, p=0.049), PLR (OR=1.12, p=0.035) and MLR (OR=1.12, p=0.030).

Conclusion

We observed neurocognitive changes related to inflammatory markers and increases in epigenetic age in healthcare personnel with post-COVID-19 condition. Future research is required to assess mental and physical health in individuals with post-COVID-19 symptoms.

Cognitive Impairment after Post-Acute COVID-19 Infection: A Systematic Review of the Literature

The present study aims to provide a critical overview of the literature on the relationships between post-acute COVID-19 infection and cognitive impairment, highlighting the limitations and confounding factors. A systematic search of articles published from 1 January 2020 to 1 July 2022 was performed in PubMed/Medline. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Only studies using validated instruments for the assessment of cognitive impairment were included. Out of 5515 screened records, 72 studies met the inclusion criteria. The available evidence revealed the presence of impairment in executive functions, speed of processing, attention and memory in subjects recovered from COVID-19. However, several limitations of the literature reviewed should be highlighted: most studies were performed on small samples, not stratified by severity of disease and age, used as a cross-sectional or a short-term longitudinal design and provided a limited assessment of the different cognitive domains. Few studies investigated the neurobiological correlates of cognitive deficits in individuals recovered from COVID-19. Further studies with an adequate methodological design are needed for an in-depth characterization of cognitive impairment in individuals recovered from COVID-19.