Multivariate profile and acute-phase correlates of cognitive deficits in a COVID-19 hospitalised cohort

#longcovid #symptoms

Introduction

Concern

There is increasing evidence that individuals who recover from COVID-19 face lasting cognitive and mental health issues. Known as Long COVID

Symptoms

The symptoms include but are not limited to β€œbrain fog,” sleep disturbances, and psychiatric disorders.

Prevalence

The prevalence of these symptoms is notably higher in severe COVID-19 cases, with up to 76% of individuals experiencing cognitive symptoms 3-6 months post-hospitalization.


Background

Objective

The objective of the study was to delve deeper into the long-term cognitive deficits experienced by individuals who had severe cases of COVID-19.

Concern

The study was propelled by the growing body of evidence suggesting persistent cognitive issues in individuals post-COVID-19.

Need

There is a pressing need for more research to confirm the association between COVID-19 and cognitive deficits and to understand the trajectory of recovery.


Evidence Before This Study

Previous Research

Before this study, there were 85 studies conducted between 2020 and 2022 that explored the chronic cognitive impairment experienced post-COVID-19.

Limitations

A significant limitation of the previous studies was their reliance on subjective reports or a lack of sensitivity to mild deficits.

Added Value of This Study

The study added value to the existing body of research by utilizing precision computerized cognitive assessment tools, which helped in finding a correlation between the scale of cognitive deficits and the severity of acute illness.


Methods

Participants

The study involved 46 individuals who had been hospitalized for COVID-19 at Addenbrooke's hospital.

Control Group

A control group of 460 individuals was established, matched for age, gender, education, and first language to ensure a balanced study.

Assessment

The assessment involved detailed computerized cognitive assessments along with scales measuring anxiety, depression, and PTSD.

Analysis

Linear modeling was employed to predict cognitive score deficits based on various factors including acute illness severity and mental health status at the time of the assessment.


Findings

Cognitive Performance

Recovered individuals exhibited diminished cognitive performance compared to the control group, characterized by slower and less accurate responses in assessments.

Affected Domains

The most affected cognitive domains were higher cognition and processing speed, distinct from cognitive decline patterns observed in normal aging and dementia.

Recovery

The study observed a slow and potentially limited recovery trajectory, albeit not reaching statistical significance.


Interpretation

Long-term Effects

The findings indicate potential long-lasting cognitive deficits in individuals recovering from severe COVID-19, particularly impacting higher cognitive functions and processing speed.

Implications

The results highlight the necessity for long-term support and rehabilitation for COVID-19 survivors experiencing cognitive deficits.


Results

Cognitive Deficits

Significant cognitive deficits were found in COVID-19 survivors compared to the control group, with acute illness severity being a substantial predictor of the scale of these deficits.

Mental Health

Chronic mental health issues were not significant predictors of cognitive deficits, emphasizing the direct impact of COVID-19 on cognitive health.


Discussion

Conclusion

The study concludes that severe COVID-19 survivors face notable cognitive deficits, comparable to the cognitive decline observed in aging individuals between the ages of 50 and 70 years.

Limitations

The study acknowledges its limitations, including a non-representative cohort and the inability to fully disentangle the underlying causes of cognitive deficits.

Future Research

The discussion underscores the need for larger-scale studies with multi-timepoint assessments to understand recovery trajectories and pinpoint the underlying causes of the observed cognitive deficits.


Sources


Notes

Severe COVID results in cognitive impairment similar to that sustained between 50 and 70 years of age and is the equivalent of losing ten IQ points. The effects are still detectable more than six months after the acute illness, and recovery is, at best, gradual.