Objective:

We report preliminary analyses of MRI measurements of white matter integrity in individuals with and without cognitive neuropsychiatric post-acute sequelae of COVID-19 (N-PASC).

Background:

Cognitive impairment is a common symptom of N-PASC and little is known about the underlying mechanism. It is characterized by deficits in executive functioning, processing speed, motor speed, attention, recall, and verbal fluency.

Design/Methods:

Participants with N-PASC (self-reported cognitive impairment >3 months after COVID-19) and controls with prior COVID without PASC underwent MR Diffusion Tensor Imaging (DTI) to assess white matter integrity (fractional anisotropy (FA); mean diffusivity (MD)). All imaging was performed on a Siemens 3T MRI scanner and a standard DTI sequence was used. Post-processing used BioImage Suite to generate data on 48 white matter tracts and group comparisons used non-parametric statistics.

Results:

14 participants with N-PASC (median age 43 [IQR 37 – 55], 79% female, median 450 days after COVID-19 [IQR 354 – 694]) and 6 controls (median age 34 [30 – 40], 67% female) underwent MRI. The groups did not differ in age, gender, or race. FA was lower in N-PASC compared to controls (C) in the corpus body (N-PASC: median of 0.61 and C: 0.64; p = 0.057) and MD was lower in the left posterior corona radiata (N-PASC: median of 0.0007 and C: 0.0008; p=0.04). A trend of lower FA was identified in corpus genu (N-PASC: median of 0.60 and C: 0.63; p = 0.11) and left stria terminalis/fornix (N-PASC: median of 0.50 and C: 0.53; p = 0.09). There was no difference between groups in the remaining tracts.

Conclusions:

We report preliminary evidence of focal damage to the corpus callosum and corona radiata in N-PASC. Damage to these tracts may play a role by affecting processing speed and communication between hemispheres. We look forward to collecting additional data to investigate the mechanism further.