Detection of elevated IL-8 and TNF-α levels later than 6 months from acute COVID-19 disease may help to identify patients at increased risk of late venous thromboembolism; nevertheless, further studies are needed to validate this observation.
VTE was diagnosed in 39.8% of 108 symptomatic post-COVID-19 patients, with 16.7% occurring during COVID-19 and 23.1% after the acute phase.
Median D-dimer was higher in patients with VTE within 6 months of COVID-19 diagnosis than in non-VTE patients, with borderline significance.
Median IL-8 was significantly higher in patients who developed VTE more than 6 months after COVID-19 than in non-VTE patients.
Median TNF-α was significantly higher in patients with late VTE (>6 months after COVID-19) than in non-VTE patients.
TNF-α concentration had the best diagnostic utility for VTE prediction in symptomatic patients diagnosed >6 months from acute infection.
TNF-α was an independent risk factor for VTE episodes in the whole study group.
This study looked at 108 people who still had breathlessness or poor exercise tolerance after having COVID-19 and were treated at a lung disease hospital department. About 4 in 10 (39.8%) had a venous blood clot, such as a clot in the lungs or legs; some occurred during the COVID-19 illness and others afterward. The researchers measured inflammation-related proteins in the blood. In people examined more than 6 months after COVID-19, those who had a clot had higher levels of IL-8 and TNF-α than those without. TNF-α was the best of the markers at distinguishing patients with clots in this later group, with moderate accuracy (AUC 0.73), and was linked to clots in the whole group independently of other factors. D-dimer, a common clot-related test, was only borderline higher in those with clots within 6 months. This research suggests that persistent inflammation might help identify people at higher risk of late clots after COVID-19. However, the study was from a single center with a small sample, so the findings need to be confirmed in larger studies before they can be used in practice.
Wyrostkiewicz D, Lewandowska K, Jankowska E, Dybowska M, Jędrych M, Zimna K, et al.. (2026). TNF-α and IL-8 Are Helpful in the Prediction of Late Post-COVID-19 Venous Thromboembolic Disease-Single-Center Prospective Study.. International journal of molecular sciences. https://doi.org/10.3390/ijms27209281