Body Mass Index Is Associated with Post-Acute Elevations in Biomarkers of Platelet Activation and Inflammation in Unvaccinated Adults Diagnosed with COVID-19 in the Previous 8 Weeks

Introduction: Obesity has arisen as a prominent risk factor for COVID-19 severity and long COVID, potentially owed in part to the obesity-induced proinflammatory state. This study aimed to examine relationships among circulating inflammatory biomarkers and body mass index in nonhospitalized adults recently diagnosed with COVID-19. Methods: This analysis included participants who completed a randomized placebo-controlled trial conducted in October 2020-March 2021. Participants (19-53 years) were unvaccinated and enrolled following COVID-19 diagnosis as allowed by CDC return-to-work guidance. Anthropometrics and biomarkers were assessed at study baseline and week four. We examined the associations between body mass index (BMI) and inflammatory biomarkers via multiple regression models. Results: At study baseline (i.e., the point of enrollment following COVID-19 diagnosis) across all participants (N = 60), a higher BMI was associated with elevations in several inflammatory biomarkers including IL-6 (β = 7.63, 95% CI = 3.54, 11.89, p = 0.0004), ferritin (β = 6.31, 95% CI = 1.97, 10.83, p = 0.0047), high sensitivity C-reactive protein (β = 13.1, 95% CI = 8.03, 18.42, p = < 0.0001), tumor necrosis factor-α (β = 3.23, 95% CI = 0.91, 5.60, p = 0.0069), IL- 12p40 (β = 3.69, 95% CI = 0.93, 6.52, p = 0.0094), IL-13 (β = 5.11, 95% CI = 1.00, 9.40, p = 0.0154), and IL-1Ra (β = 7.57, 95% CI = 3.61, 11.70, p = 0.0003). In control group participants (n = 30) after 4 weeks, a higher BMI was associated with elevations in IL-4 (β = 17.8, 95% CI = 0.84, 37.6, p = 0.0397) and sP-selectin (β = 1.16, 95% CI = 0.22, 2.11, p = 0.0182), controlling for baseline and covariates. Conclusions: Here, BMI was positively associated with circulating biomarkers of platelet activation and inflammation in adults recently diagnosed with COVID-19 after 4 weeks. The shift in post-acute COVID-19 inflammatory biomarkers associated with an increasing BMI noted here shares similarities to biomarkers of LC reported in the literature.