Atherogenic Dyslipidemia on Admission Is Associated With Poorer Outcome in People With and Without Diabetes Hospitalized for COVID-19

Assessing the causal effects of type 2 diabetes and obesity-related traits on COVID-19 severity

BACKGROUND

Type 2 diabetes (T2D) and obesity-related traits are highly comorbid with coronavirus disease 2019 (COVID-19), but their causal relationships with disease severity remain unclear. While recent Mendelian randomization (MR) studies suggest a causal link between obesity-related traits and COVID-19 severity, findings regarding T2D are inconsistent, particularly when adjusting for body mass index (BMI). This study aims to clarify these relationships.

METHODS

We applied various MR methods to assess the causal effects of BMI-adjusted T2D (T2DadjBMI) and obesity-related traits (BMI, waist circumference, and waist-hip ratio) on COVID-19 severity. Genetic instruments were obtained from large-scale genome-wide association studies (GWAS), including 898K participants for T2D and 2M for COVID-19 severity. To address potential bias from sample overlap, we conducted large-scale simulations comparing MR results from overlapping and independent samples.

RESULTS

Our MR analysis identified a significant causal relationship between T2DadjBMI and increased COVID-19 severity (OR = 1.057, 95% CI = 1.012-1.105). Obesity-related traits were also causally associated with COVID-19 severity. Simulations confirmed that MR results remained robust to sample overlap, demonstrating consistency between overlapping and independent datasets.

CONCLUSIONS

These findings highlight the causal role of T2D and obesity-related traits in COVID-19 severity, emphasizing the need for targeted prevention and management strategies for high-risk populations. The robustness of our MR analysis, even in the presence of sample overlap, strengthens the reliability of these causal inferences.

Type 2 diabetes and susceptibility to COVID-19: a machine learning analysis

BACKGROUND

Type 2 diabetes mellitus (T2DM) was one of the most prevalent comorbidities among patients with coronavirus disease 2019 (COVID-19). Interactions between different metabolic parameters contribute to the susceptibility to the virus; thereby, this study aimed to rank the importance of clinical and laboratory variables as risk factors for COVID-19 or as protective factors against it by applying machine learning methods.

METHOD

This study is a retrospective cohort conducted at a single center, focusing on a population with T2DM. The patients attended the Yazd Diabetes Research Center in Yazd, Iran, from February 20, 2020, to October 21, 2020. Clinical and laboratory data were collected within three months before the onset of the COVID-19 pandemic in Iran. 59 patients were infected with COVID-19, while 59 were not. The dataset was split into 70% training and 30% test sets. Principal Component Analysis (PCA) was applied to the data. The most important components were selected using a 'sequential feature selector' and scored by a Linear Discriminant Analysis model. PCA loadings were then multiplied by the PCs' scores to determine the importance of the original variables in contracting COVID-19.

RESULTS

HDL-C, followed by eGFR, showed a strong negative correlation with the risk of contracting the virus. Higher levels of HDL-C and eGFR offer protection against COVID-19 in the T2DM population. But, the ratio of BUN to creatinine did not show any correlation. Conversely, the AIP, TyG index and TG showed the most positive correlation with susceptibility to COVID-19 in such a way that higher levels of these factors increase the risk of contracting the virus. The positive correlation of diastolic BP, TyG-BMI index, MAP, BMI, weight, TC, FPG, HbA1C, Cr, systolic BP, BUN, and LDL-C with the risk of COVID-19 decreased, respectively.

CONCLUSION

The atherogenic index of plasma, triglyceride glucose index, and triglyceride levels are the most significant risk factors for COVID-19 contracting in individuals with T2DM. Meanwhile, high-density lipoprotein cholesterol is the most protective factor.

The prognostic significance of insulin resistance in COVID-19: a review

Objectives

Emerging publications indicate that diabetes predisposes patients with COVID-19 to more severe complications, which is partly attributed to inflammatory condition. In the current review, we reviewed recent published literature to provide evidence on the role of insulin resistance (IR) in diabetes, the association between diabetes and COVID-19 severity and mortality, the impact of COVID-19 infection on incident new-onset diabetes, mechanisms responsible for IR in COVID-19 patients, and the predictive value of different surrogates of IR in COVID-19.

Method

The literature search performs to find out studies that have assessed the association between IR surrogates and morbidity and mortality in patients with COVID-19.

Results

We showed that there is a bulk of evidence in support of the fact that diabetes is a potent risk factor for enhanced morbidity and mortality in COVID-19 patients. COVID-19 patients with diabetes are more prone to remarkable dysglycemia compared to those without diabetes, which is associated with an unfavourable prognosis. Furthermore, SARS-COV2 can make patients predispose to IR and diabetes via activating ISR, affecting RAAS signaling pathway, provoking inflammation, and changing the expression of PPARɣ and SREBP-1. Additionally, higher IR is associated with increased morbidity and mortality in COVID-19 patients and different surrogates of IR can be utilized as a prognostic biomarker for COVID-19 patients.

Conclusion

Different surrogates of IR can be utilized as predictors of COVID-19 complications and death.

COVID-19-associated hypertriglyceridemia and impact of treatment

Background

Coronavirus disease 2019 (COVID-19) associated hypertriglyceridemia was observed among patients admitted to intensive care units (ICU) in Qatar. This study aimed to describe COVID-19-associated-hypertriglyceridemia in ICU patients and the impact of treating hypertriglyceridemia on clinical outcomes.

Methods

A retrospective observational cohort study of adult patients who were admitted to the ICU with a confirmed diagnosis of COVID-19 pneumonia according to the World Health Organization criteria. Hypertriglyceridemia was defined as triglyceride level of 1.7 mmol/L (≥150 mg/dL) and severe hypertriglyceridemia as fasting TG of ≥5.6 mmol/L (≥500 mg/dL).

Results

Of 1,234 enrolled patients, 1,016 (82.3%) had hypertriglyceridemia. Median age was 50 years and 87.9% were males. Patients with hypertriglyceridemia showed significantly longer time to COVID-19 recovery, ICU and hospital stay, and time to death (29.3 vs. 16.9 days) without a difference in mortality between groups. Of patients with hypertriglyceridemia, 343 (33.8%) received treatment (i.e., fibrate and/or omega-3). Patients in treatment group showed longer time to COVID-19 recovery and hospital stay with no difference in death rates in comparison with those in no-treatment group. Relatively older patients were less likely to experience hypertriglyceridemia (odd ratio (OR) 0.976; 95% CI: 0.956, 0.995) or to receive treatment (OR 0.977; 95% CI: 0.960, 0.994). Whereas patients who received tocilizumab were more likely to experience high TG level (OR 3.508; 95% CI: 2.046, 6.015) and to receive treatment for it (OR 2.528; 95% CI: 1.628, 3.926).

Conclusion

Hypertriglyceridemia associated with COVID-19 did not increase death rate, but prolonged time to death and length of stay. Treating hypertriglyceridemia did not translate into improvement in clinical outcomes including mortality.

Hospital Readmission in Patients With Diabetic Foot Ulcers: Prevalence, Causes, and Outcomes

The aim of the current study was to evaluate the rate of readmission in patients affected by diabetes and foot ulcers (DFUs), and causes and outcomes of patients requiring a new hospitalization. The current study is a retrospective observational study including patients who have required hospitalization since January 2019 to September 2022 due to a DFU. Once patients were discharged, they were regularly followed as outpatients. Within 6 months of follow-up, the rate of hospital readmission for a diabetic foot problem was recorded. According to the readmission or not, patients were divided into 2 groups, readmitted and not readmitted patients, respectively. Hence, all patients were followed for 6 months more and outcomes of the 2 groups were analyzed and compared. Overall, 310 patients were included. The mean age was 68  ±  12 years, the majority of patients reported type 2 diabetes (>90%), and the mean diabetes duration was approximately 20 years. Sixty-eight (21.9%) patients were readmitted. The main reason for hospital readmission was the presence of critical limb ischemia (CLI) in the contralateral limb (6.1%), the recurrence of CLI in the previous treated limb (4.5%), and the onset of new infected DFU in the contralateral foot (4.5%). Readmitted patients reported lower rate of healing (51.5% vs 89.2%, P < .0001) and higher rate of major amputation (10.3% vs 4.5%, P  =  .2) in comparison to not readmitted patients. Critical limb ischemia resulted in the only independent predictor of hospital readmission. Hospital readmission is a frequent issue among patients with DFUs, and readmitted patients showed a lower chance of wound healing. Critical limb ischemia resulted in the main cause of new hospitalization.

Biomarkers of glucose homeostasis as mediators of the relationship of body mass index and waist circumference with COVID-19 outcomes among postmenopausal women: The Women's Health Initiative

BACKGROUND & AIMS

Systematic reviews, meta-analyses and Mendelian randomization studies suggest that cardiometabolic diseases may be associated with COVID-19 risk and prognosis, with evidence implicating insulin resistance (IR) as a common biological mechanism. As driving factors for IR, we examined body mass index (BMI) and waist circumference (WC) among postmenopausal women in association with COVID-19 outcomes (positivity and hospitalization), and the role of glucose homeostasis as a mediator of this relationship.

METHODS

Associations of BMI and WC at baseline (1993-1998) with COVID-19 outcomes collected at Survey 1 (June-December, 2020) and/or Survey 2 (September-December, 2021) were evaluated among 42,770 Women's Health Initiative (WHI) participants (baseline age: 59.36 years) of whom 16,526 self-reported having taken ≥1 COVID-19 test, with 1242 reporting ≥1 positive COVID-19 test and 362 reporting ≥1 COVID-19 hospitalization. We applied logistic regression and causal mediation analyses to sub-samples with available fasting biomarkers of glucose homeostasis (glucose, insulin, Homeostatic Model Assessment for Insulin Resistance, Homeostasis Model Assessment for β-cell function, Quantitative Insulin-sensitivity Check Index, Triglyceride-Glucose index (TyG)) at baseline, whereby 57 of 759 reported COVID-19 test positivity and 23 of 1896 reported COVID-19 hospitalization.

RESULTS

In fully adjusted models, higher BMI, WC and TyG were associated with COVID-19 test positivity and hospitalization. Glucose concentrations mediated associations of BMI and WC with COVID-19 positivity, whereas TyG mediated BMI and WC's associations with COVID-19 hospitalization.

CONCLUSIONS

Obesity and central obesity markers collected an average of 24 years prior were associated with COVID-19 outcomes among postmenopausal women. Glucose concentration and TyG partly mediated these associations.

Metabolic Associated Fatty Liver Disease (MAFLD) and COVID-19 Infection: An Independent Predictor of Poor Disease Outcome?

Background and Objectives: Early reports on COVID-19 infection suggested that the SARS-CoV-2 virus solely attacks respiratory tract cells. As the pandemic spread, it became clear that the infection is multiorganic. Metabolic associated fatty liver disease (MAFLD) is a chronic liver disease strongly associated with insulin resistance and diabetes. The aim of this study was to assess a possible interplay between MAFLD and COVID-19 infection and its implication in COVID-19 outcome. Materials and Methods: A retrospective observational study, including 130 COVID-19 positive patients was conducted. MAFLD diagnosis was made based on the International Consensus criteria. Patients were divided into two groups, group A (MAFLD) and group B (nonMAFLD). Anthropometric and laboratory analysis were obtained. COVID-19 severity was assessed using the NEWS2 score. Disease outcome was threefold and regarded as discharged, patients who required mechanical ventilation (MV), and deceased patients. Results: MAFLD prevalence was 42%, 67% of patients were discharged, and 19% needed MV. Mortality rate was 14%. MAFLD patients were significantly younger (p < 0.001), and had higher body mass index (p < 0.05), respiratory rate (p < 0.05) and systolic blood pressure (p < 0.05) than nonMAFLD patients. Regarding metabolic syndrome and inflammatory markers: group A had significantly higher glycemia at admission (p = 0.008), lower HDL-c (p < 0.01), higher triglycerides (p < 0.01), CRP (p < 0.001), IL-6 (p < 0.05) and ferritin (p < 0.05) than group B. MAFLD was associated with more prevalent type 2 diabetes (p = 0.035) and hypertension (p < 0.05). MAFLD patients had a more severe disease course (NEWS2 score, 6.5 ± 0.5 vs. 3 ± 1.0, p < 0.05). MAFLD presence was associated with lower patient discharge (p < 0.01) and increased need for MV (p = 0.024). Multiple regression analysis showed that BMI (p = 0.045), IL-6 (p = 0.03), and MAFLD (p < 0.05) are significant independent risk factors for a poor COVID-19 outcome. Conclusions: The prevalence of MAFLD is relatively high. MAFLD patients had a more severe COVID-19 clinical course and worse disease outcome. Our results imply that early patient stratification and risk assessment are mandatory in order to avoid poor outcomes.

Favorable Effect of Pemafibrate on Insulin Resistance and β-Cell Function in Subjects with Type 2 Diabetes and Hypertriglyceridemia: A Subanalysis of the PARM-T2D Study

Pemafibrate, a novel selective peroxisome proliferator-activated receptor modulator, has beneficial effects on lipid metabolism. However, its effects on glucose metabolism in individuals with type 2 diabetes (T2DM) remain to be fully clarified. This was a subanalysis of the PARM-T2D study, a multicenter prospective observational study on the use of pemafibrate versus conventional therapy for 52 weeks in subjects with T2DM complicated with hypertriglyceridemia. The subanalysis included participants who did not change their treatment for diabetes and did not receive insulin or insulin secretagogues during the study period. Changes in glucose metabolism markers, including homeostatic model assessment (HOMA2) scores and disposition index, were assessed. A total of 279 participants (141 in the pemafibrate group; 138 in the control group) met the criteria for the subanalysis. There were no significant changes in HbA1c during the 52-week study period in both groups. However, the pemafibrate group showed significant improvements versus the control group for insulin resistance assessed by HOMA2-R (-0.15 versus 0.08; estimated treatment difference -0.23 (95% confidence interval -0.44, -0.02); p = 0.03) and maintenance of β-cell function assessed by disposition index (0.015 versus -0.023; estimated treatment difference 0.037 (95% confidence interval 0.005, 0.069); p = 0.02). Correlation analyses showed that improvements in HOMA2-R and disposition index were significantly associated with improvements in lipid abnormalities and γ-glutamyl transpeptidase. In conclusion, pemafibrate reduced insulin resistance and maintained β-cell function in subjects with T2DM and hypertriglyceridemia, presumably by improving lipid profiles and lipid-related hepatocyte stress.

Association of triglyceride/high-density lipoprotein cholesterol ratio with severe complications of COVID-19

Background

The coronavirus disease 2019 (COVID-19) caused by the SARS-CoV-2 virus can lead to serious complications such as respiratory failure, requiring mechanical ventilation or ICU care, and can even result in death, especially in older patients with comorbidities. The ratio of triglyceride to high-density lipoprotein cholesterol (TG/HDL), a biomarker of atherosclerotic dyslipidemia and insulin resistance, is related to cardiovascular mortality and morbidity. We aimed to evaluate the link between serious complications of COVID-19 and TG/HDL in the general population.

Methods

We conducted a comprehensive analysis of 3,933 COVID-19 patients from a nationwide cohort in Korea spanning from January 1 to June 4, 2020. TG/HDL ratio was calculated from the national health screening examination data underwent before the COVID-19 infection. Serious complications of COVID-19 were defined as a composite of high-flow oxygen therapy, mechanical ventilation, admission to the intensive care unit (ICU), and mortality. We employed logistic regression analysis to investigate the relationship between the TG/HDL ratio and the likelihood of developing severe complications within 2 months of the diagnosis. To visualize this association, we used a smoothing spline plot based on the generalized additive regression model. Multivariate analysis was performed with adjustment for age, gender, body mass index, lifestyle measures, and comorbidities.

Results

Among the 3,933 COVID-19 patients, the proportion of serious complications was 7.53%. Regarding individual outcomes, the number of patients who received high-flow oxygen therapy, mechanical ventilation, ICU care, and died was 84 (2.14%), 122 (3.10%), 173 (4.40%), and 118 (3.00%), respectively. In the multivariable logistic regression, a positive association was found between TG/HDL ratio and serious complications of COVID-19 (adjusted OR, 1.09; 95% CI [1.03-1.15], p = 0.004).

Conclusion

Our study revealed a significant positive association between TG/HDL ratio and the risk of developing severe complications in COVID-19-infected patients. While this finding provides valuable insight into the potential prognostic role of TG/HDL ratio in COVID-19, further studies are needed to fully elucidate the underlying mechanisms behind this relationship.

Tirzepatide for the treatment of heart failure in Type 2 diabetes mellitus: (SUR)PASS, or not?

Type 2 diabetes mellitus (T2DM) is a rising pandemic, while cardiovascular disease, including heart failure, represents a frequent concomitance, increasing overall morbidity and mortality and, of course, healthcare cost. Tirzepatide is a dual agonist of glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 receptors, constituting a novel treatment option in T2DM. This agent exerts additional effects in addition to improvement in glycemic control, which can be of benefit for individuals with T2DM, especially those at risk for or with established cardiovascular disease or heart failure. Current evidence is limited, although suggestive of the cardiovascular safety of tirzepatide. This article provides an overview of available evidence regarding the use of tirzepatide in T2DM, with emphasis on clinical efficacy.

A metabolic blueprint of COVID-19 and long-term vaccine efficacy

Viruses are obligatory protein-coated units and often utilize the metabolic functions of the cells they infect. Viruses hijack cellular metabolic functions and cause consequences that can range from minor to devastating, as we have all witnessed during the COVID-19 pandemic. For understanding the virus-driven pathogenesis and its implications on the host, the cellular metabolism needs to be elucidated. How SARS-CoV-2 triggers metabolic functions and rewires the metabolism remains unidentified but the implications of the metabolic patterns are under investigation by several researchers. In this review, we have described the SARS-CoV-2-mediated metabolic alterations from in vitro studies to metabolic changes reported in victims of COVID-19. We have also discussed potential therapeutic targets to diminish the viral infection and suppress the inflammatory response, with respect to evidenced studies based on COVID-19 research. Finally, we aimed to explain how we could extend vaccine-induced immunity in people by targeting the immunometabolism.

Recent Pharmacological Options in Type 2 Diabetes and Synergic Mechanism in Cardiovascular Disease

Diabetes Mellitus is a multifactorial disease with a critical impact worldwide. During prediabetes, the presence of various inflammatory cytokines and oxidative stress will lead to the pathogenesis of type 2 diabetes. Furthermore, insulin resistance and chronic hyperglycemia will lead to micro- and macrovascular complications (cardiovascular disease, heart failure, hypertension, chronic kidney disease, and atherosclerosis). The development through the years of pharmacological options allowed us to reduce the persistence of chronic hyperglycemia and reduce diabetic complications. This review aims to highlight the specific mechanisms with which the new treatments for type 2 diabetes reduce oxidative stress and insulin resistance and improve cardiovascular outcomes.

Association of triglyceride-glucose index with prognosis of COVID-19: A population-based study

Background

Triglyceride-glucose (TyG) index is a simple and reliable surrogate marker for insulin resistance. Epidemiology studies have shown that insulin resistance is a risk factor for various infectious diseases. We evaluated the prognostic value of TyG index measured before the COVID-19 infection in COVID-19 infected patients.

Methods

From a nationwide COVID-19 cohort dataset in Korea, we included COVID-19 patients diagnosed between Jan and Jun 2020. Based on the nationwide health screening data between 2015 and 2018, TyG index was calculated as ln [triglyceride (mg/dL) × fasting glucose level (mg/dL)/2]. Primary outcome is development of severe complications of COVID-19 defined as composite of mechanical ventilation, intensive care unit care, high-flow oxygen therapy, and mortality within two months after the diagnosis of COVID-19.

Results

This study included 3887 patients with COVID-19 confirmed by reverse transcription polymerase chain reaction. Mean ± standard deviation of TyG index was 8.54 ± 0.61. Severe complications of COVID-19 were noted in 289 (7.44%) patients. In the multivariate logistic regression, TyG index was positively associated with severe complications of COVID-19 (adjusted odds ratio: 1.42, 95% confidence interval [1.12–1.79]).

Conclusions

In COVID-19 infected patients, high TyG index was associated with increased risk for severe complications. TyG index might be useful predictor for the severity of COVID-19 infection.

Are lipid ratios and triglyceride-glucose index associated with critical care outcomes in COVID-19 patients?

Lipid ratios and the triglyceride and glucose index (TyG) could be a simple biochemical marker of insulin resistance (IR). The current study was carried out to examine the correlation between triglyceride to high-density lipoprotein-cholesterol (TG/HDL-C), total cholesterol to HDL-C (TC/HDL-C), low-density lipoprotein-cholesterol to HDL-C ratio (LDL-C/HDL-C), as well as TyG index with the severity and mortality of severe coronavirus disease 2019 (COVID-19). A total of 1228 confirmed COVID-19 patients were included in the current research. Regression models were performed to evaluate the correlation between the lipid index and severity and mortality of COVID-19. The TyG index and TG/HDL-C levels were significantly higher in the severe patients (P<0.05). TG/HDL-C, LDL-C/HDL-C, TC/HDL-C ratios, and TyG index were significantly lower in survivor cases (P<0.05). Multivariate logistic regression analysis demonstrated that predictors of the severity adjusted for age, sex and BMI were TyG index, TG/HDL-C ratio (OR = 1.42 CI:1.10–1.82, OR = 1.06 CI: 1.02–1.11, respectively). This analysis showed that TG/HDL-C, TC/HDL-C, LDL-C/HDL-C ratios, and TyG index statistically are correlated with COVID-19 mortality (OR = 1.12 CI:1.06–1.18, OR = 1.24 CI:1.05–1.48, OR = 1.47 CI:1.19–1.80, OR = 1.52 CI:1.01–2.31, respectively). In summary, the TyG index and lipid ratios such as TC/HDL-C, TG/HDL-C, LDL-C/HDL-C could be used as an early indicator of COVID-19 mortality. Furthermore, the study revealed that TyG index and TG/HDL-C indices are biochemical markers of COVID-19 severe prognosis.

COVID-19 in Kidney Transplant Recipients With Diabetes Mellitus: A Propensity Score Matching Analysis

Kidney transplant recipients present higher rates of pre-existing comorbidities, in particular diabetes mellitus (DM), hypertension, and cardiac disease. We aimed to verify the main risk factors related to DM that contribute to COVID-19 progression and mortality in a kidney transplant setting. From March to August 2020, we evaluated 300 kidney transplant recipients affected by COVID-19. We used propensity score matching (PSM) to estimate the impact of DM on COVID-19. After matching, all baseline characteristics were well balanced between those with and without DM (n = 100 in each group). Case fatality rate, the requirement of invasive mechanical ventilation (IMV), and acute kidney injury (AKI) were associated with previous fasting blood glucose, and C-reactive protein (CRP), and lactate dehydrogenase (LDH) levels on admission. These findings were similar in kidney transplant patients with and without DM. Glycemia on admission and estimated glomerular filtration rate (eGFR) either on admission or basal correlated to the need of IMV and development of AKI, respectively. Poor glycaemic control, eGFR, markers of inflammation (CRP) and tissue damage (LDH) were indicative of COVID-19 burden in kidney transplant recipients and may be useful tools for risk-stratifying this population, independently of the DM status, during the pandemic.

HDL maturation and remodelling

Cholesterol in the circulation is mostly transported in an esterified form as a component of lipoproteins. The majority of these cholesteryl esters are produced in nascent, discoidal high density lipoproteins (HDLs) by the enzyme, lecithin:cholesterol acyltransferase (LCAT). Discoidal HDLs are discrete populations of particles that consist of a phospholipid bilayer, the hydrophobic acyl chains of which are shielded from the aqueous environment by apolipoproteins that also confer water solubility on the particles. The progressive LCAT-mediated accumulation of cholesteryl esters in discoidal HDLs generates the spherical HDLs that predominate in normal human plasma. Spherical HDLs contain a core of water insoluble, neutral lipids (cholesteryl esters and triglycerides) that is surrounded by a surface monolayer of phospholipids with which apolipoproteins associate. Although spherical HDLs all have the same basic structure, they are extremely diverse in size, composition, and function. This review is concerned with how the biogenesis of discoidal and spherical HDLs is regulated and the mechanistic basis of their size and compositional heterogeneity. Current understanding of the impact of this heterogeneity on the therapeutic potential of HDLs of varying size and composition is also addressed in the context of several disease states.

Triglyceride/High-Density Lipoprotein Cholesterol Ratio is Associated with the Mortality of COVID-19: A Retrospective Study in China

BACKGROUND

Triglyceride to high density lipoprotein cholesterol ratio (TG/HDL-c) is crucial when researching metabolic and vascular diseases, and its involvement in COVID-19 was sparsely elaborated on. The purpose of the study was to explore the inflammatory associations between the TG/HDL-c ratio and COVID-19 prognosis.

METHODS

A total of 262 COVID-19 patients consisting of 244 survivors and 18 non-survivors were retrospectively investigated. The clinical features and baseline hematological parameters were recorded and analyzed. The receiver operating characteristic curve (ROC) was used to explore the role of TG/HDL-c in predicting the mortality of COVID-19, the Spearman's rank correlation coefficients were used to measure the correlation between TG/HDL-c and inflammatory indicators, and the Kaplan-Meier (KM) curve was used to estimate the survival of COVID-19 patients with high and low TG/HDL-c ratio. Logistic regression analyses were performed to investigate the role of TG/HDL-c ratio on mortality of COVID-19 with no underlying diseases.

RESULTS

Compared with the survivors, the non-survivors of COVID-19 had significantly higher levels of white blood cells (4.7 vs 13.0 × 109/L; P < 0.001), neutrophils (3.0 vs 11.6 × 109/L; P < 0.001), C-reactive proteins (15.7 vs 76.7 mg/L; P < 0.001) and TG/HDL-c ratio (1.4 vs 2.5; P = 0.001). The ROC curve [area under the curve (AUC), 0.731; 95% confidence interval (CI), 0.609-0.853; P = 0.001] suggested that the TG/HDL-c ratio could predict the mortality of COVID-19. The TG/HDL-c ratio was positively correlated with white blood cells (r = 0.255, P < 0.001), neutrophils (r = 0.243, P < 0.001) and C-reactive proteins (r = 0.170, P < 0.006). Patients with high TG/HDL-c ratio showed a worse survival compared with those with low TG/HDL-c ratio (Log rank P = 0.003). Moreover, TG/HDL-c ratio was an independent factor in predicting the mortality of COVID-19 patients with no underlying diseases.

CONCLUSION

Our study demonstrated that TG/HDL-c ratio might potentially be a predictive marker for mortality in COVID-19 patients.

The Identikit of Patient at Risk for Severe COVID-19 and Death: The Dysregulation of Renin-Angiotensin System as the Common Theme

Since the first months of the coronavirus disease 2019 (COVID-19) pandemic, several specific physiologic traits, such as male sex and older age, or health conditions, such as overweight/obesity, arterial hypertension, metabolic syndrome, and type 2 diabetes mellitus, have been found to be highly prevalent and associated with increased risk of adverse outcomes in hospitalized patients. All these cardiovascular morbidities are widespread in the population and often coexist, thus identifying a common patient phenotype, characterized by a hyper-activation of the "classic" renin-angiotensin system (RAS) and mediated by the binding of angiotensin II (Ang II) to the type 1-receptor. At the same time, the RAS imbalance was proved to be crucial in the genesis of lung injury after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, where angiotensin-converting-enzyme-2 (ACE2) is not only the receptor for SARS-CoV-2, but its down-regulation through internalization and shedding, caused by the virus binding, leads to a further dysregulation of RAS by reducing angiotensin 1-7 (Ang 1-7) production. This focused narrative review will discuss the main available evidence on the role played by cardiovascular and metabolic conditions in severe COVID-19, providing a possible pathophysiological link based on the disequilibrium between the two opposite arms of RAS.