Differences in mortality rate among patients hospitalized with severe COVID-19 according to their body mass index.

Background: Obesity has been described as a risk factor for COVID-19 severity and mortality. Previous studies report a linear association between BMI and adverse outcomes, meanwhile in other critical illness, excessive fat tissue is related to improved survival. Whether different BMI is related with the survival of patients with severe COVID-19 deserves further analysis. Objective: To determine the mortality rate among hospitalized patients with severe COVID-19 stratified according to BMI. Methods: The clinical files of all patients hospitalized from March to December 2020 with a positive PCR test for SARS-CoV-2 discharged due to improvement or death, were analyzed. A mixed effects logistic regression was carried out to determine which clinical and biochemical characteristics and comorbidities were associated with in-hospital mortality. Results: The cohort consisted of 608 patients with a median age of 59 years (interquartile ranges, IQR 46-69 years), median BMI of 28.7 kg/m2 (IQR 25.4-32.4 kg/m2), 65.5% were male. In-hospital mortality rate was 43.4%. Of the cohort 0.8% had low weight, 20.9% normal weight, 36.0% overweight, 26.5% obesity grade I, 10.2% obesity grade II and 5.6% obesity grade III. Mortality rate was highest in patients with low weight (80%), followed by patients with obesity grade III (58.8%) and grade II (50.0%). Overweight and underweight/obesity grade III were associated with higher mortality (OR of 9.75 [1.01-1.10] and OR 4.08 [1.64-10.14]), after adjusting by sex and age. Conclusions: The patients in the underweight/overweight and grade 3 obesity categories are at higher risk of COVID-19 related mortality, compared to those with grade I or II obesity.

Reply to Scarpati, G.; Piazza, O. Comment on "Guerrero-Romero et al. Magnesium-to-Calcium Ratio and Mortality from COVID-19. Nutrients 2022, 14, 1686".

We thank Dr. Scarpati and Dr. Piazza for their interest and comments [...].

Magnesium-to-Calcium Ratio and Mortality from COVID-19.

Obesity, type 2 diabetes, arterial hypertension, decrease in immune response, cytokine storm, endothelial dysfunction, and arrhythmias, which are frequent in COVID-19 patients, are associated with hypomagnesemia. Given that cellular influx and efflux of magnesium and calcium involve the same transporters, we aimed to evaluate the association of serum magnesium-to-calcium ratio with mortality from severe COVID-19. The clinical and laboratory data of 1064 patients, aged 60.3 ± 15.7 years, and hospitalized by COVID-19 from March 2020 to July 2021 were analyzed. The data of 554 (52%) patients discharged per death were compared with the data of 510 (48%) patients discharged per recovery. The ROC curve showed that the best cut-off point of the magnesium-to-calcium ratio for identifying individuals at high risk of mortality from COVID-19 was 0.20. The sensitivity and specificity were 83% and 24%. The adjusted multivariate regression model showed that the odds ratio between the magnesium-to-calcium ratio ≤0.20 and discharge per death from COVID-19 was 6.93 (95%CI 1.6-29.1) in the whole population, 4.93 (95%CI 1.4-19.1, p = 0.003) in men, and 3.93 (95%CI 1.6-9.3) in women. In conclusion, our results show that a magnesium-to-calcium ratio ≤0.20 is strongly associated with mortality in patients with severe COVID-19.

Real-world evidence of the use of glucocorticoids for severe COVID-19.

INTRODUCTION: Currently, only glucocorticoids have proved to impact adverse outcomes in COVID-19. However, their risk/benefit balance remains inconclusive and populations' characteristics should be considered. OBJECTIVE: The objective was to evaluate the real-life use of glucocorticoids in patients with severe COVID-19 hospitalized in a third-level referral center and to determine the type, accumulated doses, and the in-hospital outcomes related with their use. METHODS: We evaluated a retrospective cohort of 737 patients with criteria for severe COVID-19 and a positive polymerase chain reaction (PCR) test for SARS-CoV-2. We extracted data for epidemiological analysis, medical history, and medications, as well as baseline laboratory tests. Data were analyzed using SPSS 21.0 and nonparametric tests, medians, and interquartile ranges (IQR). A p < 0.05 was considered significant. RESULTS: A total of 65.3% were men, with a median age of 59 years (IQR 46-70) and a median of 10 days of hospital stay (IQR 6-16), more than 40% had diabetes, hypertension, and/or obesity, and 0.8% used steroids chronically. At the time of the study, 54.0% had been discharged due to improvement and 40.8% died. The most common treatment used was dexamethasone 6 mg/day/10 days (46.6%). Patients with a complete dexamethasone scheme [as proposed by the Randomized Evaluation of COVID-19 Therapy (RECOVERY) study] had a lower mortality risk [hazard ratio (HR) 0.441, 95% confidence interval (CI) 0.232-0.840] in comparison with patients with lower doses (HR 1.803, 95% CI 1.080-3.012). Patients with methylprednisolone or several steroids tended to have higher cumulative doses (equivalent to >675 mg of prednisolone). CONCLUSION: The use of steroids in severe COVID-19 reduces mortality only at the dose proposed in the RECOVERY study in the younger population. No benefit of the use of steroids was observed in patients with older age or higher number of comorbidities.

Are overweight and obesity risk factors for invasive mechanical ventilation in severe coronavirus disease 2019 pneumonia?

OBJECTIVE: Describe the demographic, clinical, and biochemical characteristics of overweight or obese people with severe COVID-19 pneumonia and evaluate its association with mechanical ventilation requirements in a Mexican cohort. METHODS: Data were obtained from medical electronic records. Patients were divided in three groups according to the World Health Organization (WHO) classification of body mass index (BMI): lean, overweight and obese. Baseline characteristics and clinical course were compared among these 3 groups. RESULTS: The study included a total of 355 patients with confirmed COVID-19 diagnoses. Patients with obesity and overweigh, according to the WHO classification, had no significantly increased risk of requiring intubation and invasive mechanical ventilation (IMV) compared to lean subjects, with an odds ratio (OR) of 1.82 (95% CI, 0.94-3.53). A post hoc and multivariate analysis using a BMI > 35 kg/m2 to define obesity revealed that subjects above this cut off had as significantly increased risk of requiring IMV after with an OR of 2.86 (95% CI, 1.09-7.05). CONCLUSION: We found no higher risk of requiring IMV in patients with overweight or obesity while using conventional BMI cutoffs. According to our sensitivity analyses, the risk of IMV increases in patients with a BMI over 35 kg/m2.

Molecular Alterations Prompted by SARS-CoV-2 Infection: Induction of Hyaluronan, Glycosaminoglycan and Mucopolysaccharide Metabolism.

BACKGROUND: The SARS-CoV-2 is the etiological agent causing COVID-19 which has infected more than 2 million people with more than 200000 deaths since its emergence in December 2019. In the majority of cases patients are either asymptomatic or show mild to moderate symptoms and signs of a common cold. A subset of patients, however, develop a severe atypical pneumonia, with the characteristic ground-glass appearance on chest x-ray and computerized tomography, which evolves into an acute respiratory distress syndrome, that requires mechanical ventilation and eventually results in multiple organ failure and death. The Molecular pathogenesis of COVID-19 is still unknown. AIM OF THE STUDY: In the present work we performed a stringent metanalysis from the publicly available RNAseq data from bronchoalveolar cells and peripheral blood mononuclear cells to elucidate molecular alterations and cellular deconvolution to identify immune cell profiles. RESULTS: Alterations in genes involved in hyaluronan, glycosaminoglycan and mucopolysaccharides metabolism were over-represented in bronchoalveolar cells infected by SARS-CoV-2, as well as potential lung infiltration with neutrophils, T CD4+ cell and macrophages. The blood mononuclear cells presented a proliferative state. Dramatic reduction of NK and T lymphocytes, whereas an exacerbated increase in monocytes. CONCLUSIONS: In summary our results revealed molecular pathogenesis of the SARS-CoV-2 infection to bronchoalveolar cells inducing the hyaluronan and glycosaminoglycan metabolism that could shape partially the components of the ground-glass opacities observed in CT. And the potential immune response profile in COVID-19.

Increased expression of hypoxia-induced factor 1α mRNA and its related genes in myeloid blood cells from critically ill COVID-19 patients.

BACKGROUND: COVID-19 counts 46 million people infected and killed more than 1.2 million. Hypoxaemia is one of the main clinical manifestations, especially in severe cases. HIF1α is a master transcription factor involved in the cellular response to oxygen levels. The immunopathogenesis of this severe form of COVID-19 is poorly understood. METHODS: We performed scRNAseq from leukocytes from five critically ill COVID-19 patients and characterized the expression of hypoxia-inducible factor1α and its transcriptionally regulated genes. Also performed metanalysis from the publicly available RNAseq data from COVID-19 bronchoalveolar cells. RESULTS: Critically-ill COVID-19 patients show a shift towards an immature myeloid profile in peripheral blood cells, including band neutrophils, immature monocytes, metamyelocytes, monocyte-macrophages, monocytoid precursors, and promyelocytes-myelocytes, together with mature monocytes and segmented neutrophils. May be the result of a physiological response known as emergency myelopoiesis. These cellular subsets and bronchoalveolar cells express HIF1α and their transcriptional targets related to inflammation (CXCL8, CXCR1, CXCR2, and CXCR4); virus sensing, (TLR2 and TLR4); and metabolism (SLC2A3, PFKFB3, PGK1, GAPDH and SOD2). CONCLUSIONS: The up-regulation and participation of HIF1α in events such as inflammation, immunometabolism, and TLR make it a potential molecular marker for COVID-19 severity and, interestingly, could represent a potential target for molecular therapy. Key messages Critically ill COVID-19 patients show emergency myelopoiesis. HIF1α and its transcriptionally regulated genes are expressed in immature myeloid cells which could serve as molecular targets. HIF1α and its transcriptionally regulated genes is also expressed in lung cells from critically ill COVID-19 patients which may partially explain the hypoxia related events.

A Shift Towards an Immature Myeloid Profile in Peripheral Blood of Critically Ill COVID-19 Patients.

BACKGROUND: SARS-CoV-2, the etiological agent causing COVID-19, has infected more than 27 million people with over 894000 deaths worldwide since its emergence in December 2019. Factors for severe diseases, such as diabetes, hypertension, and obesity have been identified however, the precise pathogenesis is poorly understood. To understand its pathophysiology and to develop effective therapeutic strategies, it is essential to define the prevailing immune cellular subsets. METHODS: We performed whole circulating immune cells scRNAseq from five critically ill COVID-19 patients, trajectory and gene ontology analysis. RESULTS: Immature myeloid populations, such as promyelocytes-myelocytes, metamyelocytes, band neutrophils, monocytoid precursors, and activated monocytes predominated. The trajectory with pseudotime analysis supported the finding of immature cell states. While the gene ontology showed myeloid cell activation in immune response, DNA and RNA processing, defense response to the virus, and response to type 1 interferon. Lymphoid lineage was scarce. Expression of genes such as C/EBPß, IRF1and FOSL2 potentially suggests the induction of trained immunity. CONCLUSIONS: Our results uncover transcriptomic profiles related to immature myeloid lineages and suggest the potential induction of trained immunity.