In December 2019, a novel coronavirus known as SARS-CoV-2 was first detected in Wuhan, China, causing outbreaks of the coronavirus disease COVID-19 that has now spread globally. For this reason, The World Health Organization (WHO) declared COVID-19 a public health emergency in March 2020. People living with pre-existing conditions such as obesity, cardiovascular diseases, type 2 diabetes (T2D), and chronic kidney and lung diseases, are prone to develop severe forms of disease with fatal outcomes. Metabolic diseases such as obesity and T2D alter the balance of innate and adaptive responses. Both diseases share common features characterized by augmented adiposity associated with a chronic systemic low-grade inflammation, senescence, immunoglobulin glycation, and abnormalities in the number and function of adaptive immune cells. In obese and T2D patients infected by SARS-CoV-2, where immune cells are already hampered, this response appears to be stronger. In this review, we describe the abnormalities of the immune system, and summarize clinical findings of COVID-19 patients with pre-existing conditions such as obesity and T2D as this group is at greater risk of suffering severe and fatal clinical outcomes.

Background: In 2020, Ecuador had one of the highest death rates because of COVID-19. The role of clinical and biomolecular markers in COVID disease prognosis, is still not well supported by available data. In order for these markers to have practical application in clinical decision-making regarding patient treatment and prognosis, it is necessary to know an optimal cut-off point, taking into consideration ethnic differences and geographic conditions. Aim: To determine the value of clinical and biomolecular markers, to predict mortality of patients with severe COVID-19 living at high altitude. Methods: In this study, receiver operating characteristic (ROC) curves, area under the curve (AUC) of ROC, sensitivity, specificity and likelihood ratios were calculated to determine levels of clinical and biomolecular markers that best differentiate survivors versus non-survivors in severe COVID subjects that live at a high altitude setting. Results: Selected cut-off values for ferritin (≥ 1225 ng/dl, p = 0.026), IL-6 (≥ 11 pg/ml, p = 0.005) and NLR (≥ 22, p = 0.008) at 24 h, as well as PaFiO2 (≤ 164 mmHg, p = 0.015), NLR (≥ 16, p = p = 0.013) and SOFA (≥ 6, p = 0.031) at 72 h, appear to have good discriminating power to differentiate survivors versus non-survivors. Additionally, odds ratios for ferritin (OR = 3.38); IL-6 (OR = 17.07); PaFiO2 (OR = 4.61); NLR 24 h (OR = 4.95); NLR 72 h (OR = 4.46), and SOFA (OR = 3.77) indicate increased risk of mortality when cut-off points were taken into consideration. Conclusions: We proposed a straightforward and understandable method to identify dichotomized levels of clinical and biomolecular markers that can discriminate between survivors and non-survivors patients with severe COVID-19 living at high altitudes.

Background: There is increasing evidence that inflammation is an important determinant in COVID-19 pathogenesis. Several studies describe cytokines and microRNAs as important regulators of immune and inflammatory responses in other diseases, regarding them as valuable biomarkers. Aim: Identify a potential relationship between cytokines (interleukin [IL]-6, IL-8) and microRNAs (miR-146a-5p, miR-155-5p) and clinical characteristics of COVID-19 patients, focusing on disease severity and mortality risk. Methods: Serum expression levels of miR-146a, miR-155, IL-6, IL-8, C-reactive protein, ferritin, and neutrophil-to-lymphocyte ratio, of 25 mild, 73 moderate, and 39 severe COVID-19 patients from Quito-Ecuador, were determined to correlate outcomes with clinical parameters. Results: In all groups, overweight and obesity were the most prevalent comorbidities (75.91%). Serum levels of IL-6 were significantly elevated in patients with moderate and severe COVID-19 (analysis of variance [ANOVA] p ≤ 0.000). miR-146a was significantly decreased in moderate and severe COVID-19 patients when compared with mild cases (ANOVA p = 0.002). ROC curve analysis showed that selected cut-off values for miR-146a > 3.999 ΔCt for mild vs moderate condition (sensitivity 83.56%, specificity 48%) and miR-146a > 3.999 ΔCt for mild vs severe condition (sensitivity 84.62%, specificity 40%), and IL-6 ≥ 72.25 pg/mL (sensitivity 78.95%, specificity 60.61%) when combined with clinical pretest probability, can be used to predict aggravation and death in COVID-19 patients. Odds ratios (ORs) of miR-146a (OR = 4.322) and IL-6 (OR = 3.198) indicate an increased risk of worsening and death, respectively, when cut-off points were taken into consideration. Conclusion: This study shows that elevated inflammatory IL-6 and decreased serum levels of anti-inflammatory miR-146a-5p can be discriminatory markers of COVID-19 severity and mortality.

Background In 2020, Ecuador had one of the highest death rates because of COVID-19. The role of clinical and biomolecular markers in COVID disease prognosis, is still not well supported by available data. In order for these markers to have practical application in clinical decision-making regarding patient treatment and prognosis, it is necessary to know an optimal cut-off point, taking into consideration ethnic differences and geographic conditions. Aim: To determine the value of clinical and biomolecular markers, to predict mortality of patients with severe COVID-19 living at high altitude. Methods: In this study, receiver operating characteristic (ROC) curves, area under the curve (AUC) of ROC, sensitivity, specificity and likelihood ratios were calculated to determine levels of clinical and biomolecular markers that best differentiate survivors versus non-survivors in severe COVID subjects that live at a high altitude setting. Results: Selected cut-off values for ferritin (≥ 1225 ng/dl, p = 0.026), IL-6 (≥ 11 pg/ml, p = 0.005) and NLR (≥ 22, p = 0.008) at 24 hours, as well as PaFiO2 (≤ 164 mmHg, p = 0.015), NLR (≥ 16, p = p = 0.013) and SOFA (≥ 6, p = 0.031) at 72 hours, appear to have good discriminating power to differentiate survivors versus non-survivors. Additionally, odds ratios for ferritin (OR = 3.38); IL-6 (OR = 17.07); PaFiO2 (OR = 4.61); NLR 24h (OR = 4.95); NLR 72h (OR = 4.46), and SOFA (OR = 3.77) indicate increased risk of mortality when cut-off points were taken into consideration. Conclusions: We proposed a straightforward and understandable method to identify dichotomized levels of clinical and biomolecular markers that can discriminate between survivors and non-survivors patients with severe COVID-19 living at high altitudes.