Epicardial fat inflammation response to COVID-19 therapies

Objective: Adipose tissue plays a role in the novel coronavirus disease 2019 (COVID-19). Epicardial adipose tissue (EAT), a unique visceral fat, presents with high degree of inflammation in severe COVID-19 disease. Whether and how adipose tissue may respond to the COVID-19 therapies is unknown. Methods: We retrospectively analyzed the difference in computed tomography (CT) measured EAT and subcutaneous (SAT) attenuation, defined as mean attenuation expressed in Hounsfield units (HU), in 72 patients [mean±SD age was 59.6±12.4 years, 50 (69%) were men] at the hospital admission for COVID-19 and 99 days [IQR (71-129)] after discharge. Results: At the admission, EAT HU was significantly correlated with blood glucose levels, interleukin 6 , troponin T levels and waist circumference. EAT HU decreased from -87.21±16.18 to -100.0±11 (p<0.001) whereas SAT HU did not change (-110.21±12.1 to -111.11±27.82, p=0.78) after therapy. Changes in EAT HU (expressed as ∆) significantly correlated with dexamethasone therapy (r= - 0.46, p= 0.006), and when dexamethasone was combined with tocilizumab (r= -0.24, p=0.04). Conclusions: Dexamethasone therapy was associated with significant reduction of EAT inflammation in COVID-19 patients, whereas SAT showed no changes. Anti-inflammatory therapies targeting visceral fat may be helpful in COVID-19 diseases.