Fluorodeoxyglucose Positron Emission Tomography Detects Persistent Arterial Inflammation After Symptomatic COVID-19

There is limited knowledge of persisting vascular and systemic inflammation in adults recovered from COVID-19. This study aimed to assess whether inflammation from symptomatic mild-to-moderate COVID-19 persists beyond the apparent clinical resolution of disease using fluorodeoxyglucose positron emission tomography (FDG-PET).

This observational single-centre cohort study invited adults (aged >40 years) who had clinically recovered from mild-to-moderate COVID-19. Whole-body FDG-PET imaging and C-reactive protein test were performed on the same day after a minimum of 30 days after COVID-19 diagnosis. COVID-19-naive adults at high-risk for cardiovascular disease (CVD) were included for comparison (n=8); thoracic FDG-PET imaging was performed for these participants.

FDG-PET imaging was performed after a median of 97 days (interquartile range [IQR] 75-113 days) after COVID-19 diagnosis. Participants who recovered from COVID-19 showed an increased arterial inflammation (median standard uptake value [SUV]_max 3.1; IQR 2.7-3.3) compared with the high-risk participants with CVD (median SUV_max 2.5; IQR 2.2-2.8; p<0.001). There was a moderate positive correlation between the total thoracic SUV_max and the bone marrow SUV_mean (Spearman r=0.58; p<0.001) and the spleen mean SUV_max (Spearman r=0.62, p<0.001) for participants who recovered from COVID-19.

Ongoing arterial inflammation is detected by FDG-PET imaging after mild-to-moderate COVID-19. Larger prospective studies are needed to assess the implications on CVD risk.