The Potential Effect Of Leptin And Il-6 Levels On Covid-19 Severity In Obese Patients

Background: The obesity is one of the high-risk factors in COVID-19 in severe illness and mortality as the pandemic progresses. The pleotropic Leptin is a polypeptide hormone and secreted by adipose tissues. It acts as a proinflammatory cytokine. Leptin is associated with severe conditions known to cause the risk of COVID-19 severity. Acute changes in calorie intake affect Leptin levels, which in turn are related to the amount of adipose tissue. Interleukin 6 (IL-6) also is a pleiotropic cytokine (184 amino acid) and initiates different inflammatory responses in tissues. The aim of study: The aim of this study is to evaluate the effect of Leptin and IL-6 levels on the COVID-19 severity of an early diagnosis in obese patients infected with COVID-19. Materials and Methods: This case-control study included 60 obese subjects, divided to 30 obese without any chronic disease and not infected with COVID-19, and 30 individuals were infected with COVID-19, with the age ranged between (25-60) years. COVID-19 patients divided into three categories, (13 mild/moderate), (10 severe) and (7 dead). And thirty (20 male and 10 female) apparently healthy subjects as control group. Their age and sex were comparable to the patients. The enzyme-linked immunosorbent assay (ELISA) kits used to measure serum Leptin and IL-6 levels. Results: Leptin concentration and IL-6 concentration were significantly higher in obese COVID-19 patients than the obese without COVID-19 and normal weight control group (11.80 +/- 1.38, 344.23 +/- 70.13 vs 8.64 +/- 1.21, 790.34 +/- 194.29 vs 4.09 +/- 2.15, 138.89 +/- 46.36) respectively. However, especially in dead and severe cases increased levels of IL-6 and Leptin than the mild/moderate cases of obese patients infected with COVID-19. Serum leptin level has a positive significant correlation with levels of IL-6, D-dimer, ferritin and NLR in obese COVID-19 patients group. Conclusions: High circulating IL-6 and Leptin in the obese patients might involve dysregulation of proinflammatory cytokines in obesity and may be used as a useful prognostic tool associated with COVID-19 to predict the SARS-COV-2 severity.