Long COVID and Cognitive Deficits: Urgent Action Needed for Mental Health Awareness

Understanding the Impact of COVID-19 on Cognitive Health

Introduction to COVID-19 and Long COVID

Since its emergence in 2020, COVID-19 has profoundly affected millions worldwide. The SARS-CoV-2 virus, responsible for the disease, has prompted scientists to closely monitor individuals who have contracted it to grasp both immediate and prolonged effects, particularly concerning cognitive health related to ‘Long COVID.’ A recent study conducted by researchers from the University of Cambridge and the University of Exeter focuses on patients experiencing cognitive difficulties linked to long COVID. Their findings, detailed in a report published in Frontiers in Aging Neuroscience, highlight the cognitive repercussions of SARS-CoV-2 infection.

Defining Long COVID

Long COVID refers to the persistent illness experienced after SARS-CoV-2 infection, characterized by symptoms that resemble those present during the initial illness but endure for over twelve weeks. These symptoms cannot be attributed to any other health condition. It is estimated that long COVID affects approximately 10-25% of individuals who have had COVID-19, with cognitive dysfunction being one of the most prevalent symptoms, reported by around 70% of long COVID patients.

Study Overview

To investigate the long-term cognitive effects of SARS-CoV-2, a study involving 421 participants aged 18 and older was conducted. This group included both COVID-19 survivors and individuals who had never contracted the virus. Participants were assessed on cognitive tests alongside their reported ongoing symptoms.

Cognitive Functioning Among COVID-19 Survivors

The study found that approximately 77.8% of participants with ongoing symptoms experienced difficulties concentrating, 69% reported brain “fog,” 43.7% experienced semantic disfluency, and 59.5% struggled to find the right words while speaking. COVID-19 survivors were categorized into three groups based on their ongoing symptoms: “Recovered” (no symptoms), “Mild/Moderate” (mild ongoing symptoms), and “Severe” (severe ongoing symptoms).

Assessment of Cognitive Performance

Researchers employed six cognitive tests to evaluate various aspects of cognitive performance, including memory, category fluency, executive function reaction time, and executive function performance. Key tests included the “Word List Recognition Test,” which assessed memory recall, and the “Pictorial Associative Memory Test,” which evaluated the ability to remember visual associations.

Findings on Memory Impairment

Analysis revealed that participants with a history of COVID-19 performed significantly worse on the “Word List Recognition Test” compared to those who had never contracted the virus, exhibiting longer reaction times. Similar trends were observed in the pictorial associative memory test, although the reaction times did not show significant differences.

Severe Long COVID Symptoms and Cognitive Performance

Participants reporting severe long COVID symptoms performed poorly on the “Word List Recognition Test,” providing fewer correct answers than those without a COVID history. Additionally, those classified as “Recovered” exhibited slower reaction times compared to the “no COVID” group, while the “Mild/Moderate” group also demonstrated slower reaction times than both the “no COVID” and recovered groups.

Expert Commentary

Dr. Lucy Cheke, the senior author of the study and a researcher at the University of Cambridge, emphasized that cognitive issues associated with long COVID are often underestimated. She noted that while fatigue and cough are commonly recognized, cognitive dysfunction, being the second most frequent symptom, significantly impacts memory capabilities. Previous research suggests that SARS-CoV-2 may lead to brain alterations, including the loss of gray matter in various brain regions.

Link Between Initial Illness Severity and Long COVID Symptoms

The research highlighted that individuals exhibiting more severe initial COVID-19 symptoms are more likely to experience significant lasting cognitive symptoms compared to those with milder initial presentations. For instance, a severe headache during the early phase of the infection was linked to diminished performance on cognitive tests.

Addressing Cognitive Impairment Post-COVID-19

Approximately 50% of participants with enduring cognitive impairments reported challenges in convincing healthcare professionals to acknowledge their conditions. Furthermore, 75% indicated that they had to take time off work due to persisting symptoms. Dr. Cheke expressed concern over the lack of political and medical attention towards long COVID, urging for greater consideration of cognitive issues as part of the overall impact of the pandemic.

Future Research Directions

This study focused solely on individuals infected with the original or alpha variant of SARS-CoV-2. Researchers are now recruiting participants who have contracted the Omicron and Delta variants to extend their understanding of cognitive effects and improve support for recovery.

References

1. Guo, P. et al. (2022). COVCOG 2: Cognitive and Memory Deficits in Long COVID: A Second Publication From the COVID and Cognition Study. Frontiers in Aging Neuroscience. doi: 10.3389/fnagi.2022.804937.
2. COVID-19 Rapid Guideline: Managing The Long-Term Effects of COVID-19. (2020). National Institute for Health and Care Excellence. Retrieved from https://www.nice.org.uk/guidance/ng188.
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7. Guo, P. et al. (2022). COVCOG 1: factors predicting cognitive symptoms in Long COVID. A first publication from the COVID and Cognition Study. Frontiers in Aging Neuroscience. doi: 10.3389/fnagi.2022.804922.
8. Garget, Jacqueline. (2022). Memory and concentration problems are common in Long COVID and must not be ignored, says scientists. EurekAlert! Accessed Mar. 23, 2022. Retrieved from https://www.eurekalert.org/news-releases/946155.
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