Elevated cerebral oxygen extraction in patients with post-COVID conditions

Area of Science:

• Neurology
• Cardiovascular Science
• Infectious Disease

Background:

• Neurological symptoms in post-COVID-19 conditions (neuro-PCC) may stem from impaired cerebral microcirculation and altered brain oxygen homeostasis due to SARS-CoV-2 infection.
• Investigating cerebral oxygen delivery and consumption balance is crucial for understanding neuro-PCC.

Purpose of the Study:

• To investigate the oxygen extraction fraction (OEF) in patients experiencing neuro-PCC.
• To explore the relationship between OEF and neurobehavioral deficits in neuro-PCC patients.

Main Methods:

• Utilized TRUST MRI to quantify global OEF in 25 neuro-PCC patients (8 hospitalized, 17 not) and 59 healthy controls.
• Compared OEF across groups, accounting for age and sex.
• Assessed associations between OEF and neurobehavioral measures in neuro-PCC participants.

Main Results:

• A significant difference in OEF was observed among the three groups (p=0.046).
• Previously hospitalized neuro-PCC patients exhibited significantly higher OEF (42.40±5.40%) compared to uninfected controls (37.70±5.09%) and non-hospitalized neuro-PCC patients (37.02±5.05%).
• In neuro-PCC patients, OEF correlated significantly with locomotor function, specifically 4-m walk gait speed (β=-0.03, r=0.34, p=0.003).

Conclusions:

• Neuro-PCC is associated with altered cerebral OEF.
• Elevated OEF in neuro-PCC patients, especially those previously hospitalized, indicates potential cerebral oxygenation imbalances.
• OEF serves as a promising biomarker for neuro-PCC research and may correlate with functional deficits like reduced mobility.