Why Screening for COVID-19 Cognitive Impairment Matters

Exploring COVID-19’s short- and long-term cognitive effects
The connection between severe illness and cognitive impairment has been well-established. Two-thirds of patients who spend time in the ICU develop cognitive effects from inflammation, changes in blood pressure, and medication side effects. However, most cases of post-viral cognitive impairment resolve naturally over the course of a few months.

However, COVID-19 illness is unique in that a subset of patients develop persistent cognitive deficits. One study found that 25% of COVID patients had difficulty with memory encoding, 23% struggled with memory recall, and 18% had trouble processing information seven months later.

Severe COVID-19 may cause cognitive impairment on par with aging 20 years or dropping 10 IQ points, according to another study, but even mild cases of COVID have resulted in what’s referred to as “long COVID,” characterized by brain fog, inattentiveness, memory loss, depression, anxiety, fatigue, disturbed sleep, and executive function impairment.

Potential cause of long COVID-19 cognitive impairment
Autopsy brain samples have suggested that a late and heightened immune response may trigger inflammation and microglia dysregulation in COVID patients, similar to what people experience on the chemotherapy drug methotrexate. Follow-up studies identified two heightened inflammatory markers in the cerebrospinal fluid of COVID patients with cognitive symptoms compared to those without. Researchers believe this type of cognitive impairment could potentially be reversible and remain hopeful that therapies in development for “chemobrain” may one day help patients with long COVID brain fog.

Can COVID-19 related brain changes become permanent?
It’s still too early to know the full implications of widespread cognitive impairment, but scans have shown structural changes to the brain, including widespread tissue damage and 0.2-2% more gray matter loss than what is observed through normal aging. Scientists said the long-term implications were unclear and it was unknown whether these effects could be reversed.

Further, the University of Missouri School of Medicine’s assessment of 10,403 patients with COVID-19 related pneumonia found a 1.5% higher rate of new onset dementia compared to patients with other types of pneumonia. All told, 3% of hospitalized patients with COVID-19 pneumonia—particularly those over 70—developed dementia affecting memory, self-regulation, and the ability to perform daily tasks.

Testing leads to helpful interventions
So far, clinicians have noted a number of interventions that prove helpful among patients with long COVID cognitive impairments, such as:

• 90 minute group therapy sessions focusing on self-management techniques to cope with fatigue, brain fog, sleep habits, activity pacing, and energy conservation
• Pursed lip breathing to increase oxygenation and decrease physical exertion
• Use of adaptive equipment like long-handle dressing equipment and reachers
• Graded exposure of endurance activities under direct supervision
• Use of a pulse oximeter to monitor oxygen saturation zone
• Multidisciplinary physical therapy, recreational therapy, and holistic wellness counseling

Screen patients for COVID-19 cognitive impairment with MoCA
MoCA can be used for the early detection of COVID-related neurological issues such as brain fog, mild cognitive impairment related to pneumonia, and increased risk of dementia.

Testing cognitive impairment with MoCA has been validated by multiple peer-reviewed studies:

• “Our meta-analysis revealed that people with COVID-19 had poorer general cognitive functioning compared to people without COVID-19 in the acute phase and 6 months after infection. MoCA was the most commonly used tool in the studies reported in this review.” Post-COVID, researchers found more than half of the 290 patients studied showed evidence of memory impairment, semantic verbal fluency, attention, and executive functions. This study highlighted the importance of systematic cognitive screening in COVID-19 patients after illness.1

• “We found lower total MoCA scores in survivors of COVID-19 compared with control patients. A subgroup of survivors… were significantly associated with improvement six months later.” A case-control study of 85 COVID patients found a mean MoCA score of 19.2 at discharge, which improved to a mean score of 26.1 six months later.2

• “Based on our results, MoCA was more sensitive in detecting cognitive functions impairments…. MoCA, which includes more testing of cognitive subdomains than MMSE, was thus designed to be more sensitive and may therefore represent a superior screening instrument to detect wide ranges of cognitive impairments.” Analysis of 87 COVID-19 patients showed significant cognitive impairments in memory, attention, abstraction, and space-time orientation. One month after discharge, 70% of patients showed signs of dysfunction and 25% needed specialized rehabilitation plans. One month after infection, many patients improved performance in language abilities, but memory dysfunctions commonly persisted. MoCA’s sensitivity was better suited to detect visuospatial and executive function impairments than the MMSE.3

• “Asymptomatic COVID-19 subjects secured lower scores in certain domains of the MoCA in comparison with the controls. The domains were visuoperception, naming and fluency. Also, older aged COVID-19 positive subjects scored lower in the MoCA when compared to the younger people.” This study of 93 asymptomatic COVID patients and 102 controls highlights the importance of testing to ensure that elderly patients received the daily living care and monitoring they need to navigate cognitive impairments. The study also found younger and asymptomatic COVID-19 subjects had cognitive deficits in certain subdomains, suggesting the need for detailed psychometric assessments to ensure they receive support to successfully return to work.4

• “Rural residents were willing to participate in telephone-based health-seeking activities during quarantine, and the Moca-Telephone was useful in identifying cognitive risk.” Telephone-based screening and education sessions took off during the COVID-19 pandemic. Of the 60 patients who completed the MoCA-T telehealth screening, 25% were found to be at risk for memory impairment. Of those at-risk patients, 12/15 followed up with their health care providers, showing promise for the use of telehealth tools to deliver better post-COVID care.s

The importance of cognitive impairment screening in the coming years cannot be overstated as we continue to assess how the novel coronavirus impacts our patients in the long term. We remain hopeful that early testing and therapeutic interventions can improve functioning and quality of life, despite these impairments. At the very least, understanding a patient’s baseline ensures we set patients up with appropriate care, monitoring, and referrals in the post-acute rehabilitation stage of recovery.

References:

1 Crivelli, L, Palmer, K, Calandri, I, et al. Changes in cognitive functioning after COVID-19: A systematic review and meta-analysis. Alzheimer’s Dement. 2022; 1 20. https://doi.org/10.1002/alz.12644

2 Nersesjan V, Fonsmark L, Christensen RHB, et al. Neuropsychiatric and Cognitive Outcomes in Patients 6 Months After COVID-19 Requiring Hospitalization Compared With Matched Control Patients Hospitalized for Non–COVID-19 Illness. JAMA Psychiatry. Published online March 23, 2022. https://jamanetwork.com/journals/jamapsychiatry/fullarticle/2790554

3 Pistarini C, Fiabane E, Houdayer E, Vassallo C, Manera MR, Alemanno F. Cognitive and Emotional Disturbances Due to COVID-19: An Exploratory Study in the Rehabilitation Setting. Front Neurol. 2021;12:643646. Published 2021 May 17. doi:10.3389/fneur.2021.643646 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8165252/

4 Amalakanti, S., Arepalli, K.V.R. & Jillella, J.P. Cognitive assessment in asymptomatic COVID-19 subjects. VirusDis. 32, 146–149 (2021). https://link.springer.com/article/10.1007/s13337-021-00663-w

5 Wiese, L.A.K., Williams, I.C., Schoenberg, N.E., Galvin, J.E. and Lingler, J.H. (2021), Employing the Moca-T (telephone) as a means of cognitive screening in a rural, ethnically diverse population during Covid-19 restrictions. Alzheimer’s Dement., 17: e055624. https://alz-journals.onlinelibrary.wiley.com/doi/abs/10.1002/alz.055624

‍