Long-term Effects of COVID-19 on Vascular Parameters-A Prospective Longitudinal Ultrasound Clinical Study

Objective: To investigate the longitudinal effects of COVID-19 on major vascular structures and parameters and clinical outcomes.

Design: Observational prospective trial.

Setting: Post-COVID-19 research clinic established by University of Louisville Division of Infectious Diseases.

Participants: The study population consisted of 72 post-COVID-19 individuals and 11 non-COVID-19 infected participants in the control group. The participants were recruited from adult hospitals and from the community. The enrollment started in October 2020 and follow-up periods were at 3, 6, and 12 months from their initial COVID-19 diagnosis.

Interventions: The participants were interviewed for medical and COVID-19 infection history. Samples of white blood cell (WBC), C-reactive protein (CRP), and D-dimer were taken at each visit. Certified sonographers performed vascular ultrasound on the study participants.

Measurements and main results: Median intima-media thickness (IMT) was increased in mild/asymptomatic (0.80 mm) and severe/critical (0.90 mm) groups when compared with controls (0.60 mm; P < .001 for both groups). In the asymptomatic/mild group, 6-month median IMT (0.88 mm) was increased, compared with the 3-month group (0.75 mm), with P = .026. Increased age was associated with decreased mean arterial blood velocities (cm/s): common carotid (r = -0.236, P = .032), internal carotid (r = -0.208, P = .048), and subclavian artery mean velocity (r = -0.357, P = .003). We did not find any instance of deep vein thrombosis. Median D-dimer, CRP, and WBC in the control group differed from asymptomatic/mild COVID-19 group (P = .026, .011, and .003, respectively). Moreover, WBC in the asymptomatic/mild group and moderate COVID-19 group differed from severe/critical group (P = .025 and P = .027, respectively); CRP also differed between asymptomatic/mild group and severe/critical group (P = .014).

Conclusions: There were differences in intima-media lumen thickness (IMT), arterial velocities, and inflammatory markers in post-COVID-19 patients. There was no instance of deep vein thrombosis in this post-COVID-19 study cohort. The increased IMT might infer atherosclerosis, which has shown to increase cardiovascular risks. It is not yet known whether the increase in IMT due to COVID should be treated in the same way as non-COVID-19 atherosclerosis-through statins, for example-or whether regular cardiovascular risk reduction would be useful. Clinical trial and mechanistic studies should be performed to further our understanding of COVID-19-related vascular pathologies.