Predictive value of HbA1c for in-hospital adverse prognosis in COVID-19: A systematic review and meta-analysis

Lower Glycosylated Hemoglobin Is Associated With Lower In-Hospital Mortality in Patients With COVID-19: A Systematic Review of the Literature and Meta-Analysis

OBJECTIVE

Poor glycemic control during COVID-19 hospitalization is associated with higher mortality. However, the association between long-term glycemic control, as reflected by the glycosylated hemoglobin (HbA1c) and outcomes has yet to be clarified, with some studies reporting no association. The aim of this study is to determine the association between HbA1c and in-hospital mortality in patients with COVID-19.

METHODS

Pubmed, Embase, and Web of Science databases were searched for studies examining the association between HbA1c level and in-hospital COVID-19 mortality. Random-effects meta-analysis was performed. Heterogeneity was assessed using the I2 statistic. Publication bias was assessed using funnel plots.

RESULTS

Among 4142 results, 22 studies were included in the final analysis with a total of 11 220 patients. Lower Hba1c was associated with lower in-hospital mortality [odds ratio (OR), 0.53; 95% CI, 0.37-0.76; I2 81%], in using HbA1c as a dichotomous variable. When only patients with diabetes were included in the analysis, the association remained statistically significant (OR, 0.67; 95% CI, 0.47-0.96). In the subgroup analysis, the association remained statistically significant in studies using as cutoff the HbA1c value of 6.5% (OR, 0.34; 95% CI, 0.15-0.77) and 7% (OR, 0.54; 95% CI 0.32-0.90), but not with greater HbA1c cutoff values; 7.5% and ≥8%. In studies using HbA1C as a continuous variable, HbA1c level did not have a statistically significant association with in-hospital mortality, either in univariate or multivariate analyses.

CONCLUSION

A better glycemic control prior to hospitalization, as reflected by lower HbA1c, is associated with lower in-hospital mortality in patients with COVID-19.

Random Blood Glucose, but Not HbA1c, Was Associated with Mortality in COVID-19 Patients with Type 2 Diabetes Mellitus-A Retrospective Study

Previous studies have yielded inconsistent results on whether glycated hemoglobin (HbA1c) and random blood glucose (RBG) are associated with mortality of coronavirus disease 2019 (COVID-19) patients with type 2 diabetes mellitus (T2DM). This study aimed to assess the association of HbA1c and RBG with mortality among COVID-19 patients with T2DM. A retrospective study was conducted on 237 patients with COVID-19 and T2DM (survival (n = 169) and non-survival groups (n = 68)). Data on socio-demography, comorbidities, clinical symptoms, laboratory examination, and mortality were collected. Patients in the non-survival group had an older age range as compared with those in the survival group (60 (52.3-65.0) vs. 56.0 (48.5-61.5) years, p = 0.009). There was no statistical gender difference between the two groups. After matching was done, chronic kidney disease, NLR, d-dimer, procalcitonin, and random blood glucose were higher in the non-survival group compared to the survival group (p < 0.05). HbA1c levels were similar in survivors and non-survivors (8.7% vs. 8.9%, p=0.549). The level of RBG was independently associated with mortality of COVID-19 patients with T2DM (p = 0.003, adjusted OR per 1-SD increment 2.55, 95% CI: 1.36-4.76). In conclusion, RBG was associated with the mortality of COVID-19 patients with T2DM, but HbA1c was not.

D-dimer and HbA1c levels findings in COVID-19 Iraqi patients

On March 11, 2020, the World Health Organization (WHO) declared a new coronavirus infection caused by the SARS-CoV-2 virus as a pandemic, making it the 11th pandemic of the 20th and 21st centuries. This study investigated the clinical and laboratory results (D-dimer, conventional coagulation, and HbA1c biomarker concentrations) of 150 patients (75 male and 75 female) with confirmed COVID-19 pneumonia and 50 controls (25 male and 25 female). For disease diagnosis, all COVID-19 patients were given a Real-Time Reverse Transcription Polymerase Chain Reaction Assay (RT-PCR). The findings revealed that D-dimer and HbA1c levels in COVID-19 patients were significantly higher (P 0.001) at the time of admission; In COVID-19 patients, there was also a strong correlation between D-dimer levels and HbA1c levels (P 0.001). In conclusion, COVID-19 patients are more likely to have a poor prognosis if their D-dimer and HbA1c levels remain uncontrolled over a lengthy period. To lower the likelihood of a bad prognosis in COVID-19, patients with higher levels of D-dimer and HbA1c should be continuously monitored.

Impact of upper and lower respiratory symptoms on COVID-19 outcomes: a multicenter retrospective cohort study

BACKGROUND

Respiratory symptoms are associated with coronavirus disease 2019 (COVID-19) outcomes. However, the impacts of upper and lower respiratory symptoms on COVID-19 outcomes in the same population have not been compared. The objective of this study was to characterize upper and lower respiratory symptoms and compare their impacts on outcomes of hospitalized COVID-19 patients.

METHODS

This was a multicenter, retrospective cohort study; the database from the Japan COVID-19 Task Force was used. A total of 3314 COVID-19 patients were included in the study, and the data on respiratory symptoms were collected. The participants were classified according to their respiratory symptoms (Group 1: no respiratory symptoms, Group 2: only upper respiratory symptoms, Group 3: only lower respiratory symptoms, and Group 4: both upper and lower respiratory symptoms). The impacts of upper and lower respiratory symptoms on the clinical outcomes were compared. The primary outcome was the percentage of patients with poor clinical outcomes, including the need for oxygen supplementation via high-flow oxygen therapy, mechanical ventilation, and extracorporeal membrane oxygenation or death.

RESULTS

Of the 3314 COVID-19 patients, 605, 1331, 1229, and 1149 were classified as Group 1, Group 2, Group 3, and Group 4, respectively. In univariate analysis, patients in Group 2 had the best clinical outcomes among all groups (odds ratio [OR]: 0.21, 95% confidence interval [CI]: 0.11-0.39), while patients in Group 3 had the worst outcomes (OR: 3.27, 95% CI: 2.43-4.40). Group 3 patients had the highest incidence of pneumonia, other complications due to secondary infections, and thrombosis during the clinical course.

CONCLUSIONS

Upper and lower respiratory tract symptoms had vastly different impacts on the clinical outcomes of COVID-19.

Gene Networks of Hyperglycemia, Diabetic Complications, and Human Proteins Targeted by SARS-CoV-2: What Is the Molecular Basis for Comorbidity?

People with diabetes are more likely to have severe COVID-19 compared to the general population. Moreover, diabetes and COVID-19 demonstrate a certain parallelism in the mechanisms and organ damage. In this work, we applied bioinformatics analysis of associative molecular networks to identify key molecules and pathophysiological processes that determine SARS-CoV-2-induced disorders in patients with diabetes. Using text-mining-based approaches and ANDSystem as a bioinformatics tool, we reconstructed and matched networks related to hyperglycemia, diabetic complications, insulin resistance, and beta cell dysfunction with networks of SARS-CoV-2-targeted proteins. The latter included SARS-CoV-2 entry receptors (ACE2 and DPP4), SARS-CoV-2 entry associated proteases (TMPRSS2, CTSB, and CTSL), and 332 human intracellular proteins interacting with SARS-CoV-2. A number of genes/proteins targeted by SARS-CoV-2 (ACE2, BRD2, COMT, CTSB, CTSL, DNMT1, DPP4, ERP44, F2RL1, GDF15, GPX1, HDAC2, HMOX1, HYOU1, IDE, LOX, NUTF2, PCNT, PLAT, RAB10, RHOA, SCARB1, and SELENOS) were found in the networks of vascular diabetic complications and insulin resistance. According to the Gene Ontology enrichment analysis, the defined molecules are involved in the response to hypoxia, reactive oxygen species metabolism, immune and inflammatory response, regulation of angiogenesis, platelet degranulation, and other processes. The results expand the understanding of the molecular basis of diabetes and COVID-19 comorbidity.

Glycaemic variability is associated with all-cause mortality in COVID-19 patients with ARDS, a retrospective subcohort study

There is high mortality among intensive care unit (ICU) patients with acute respiratory distress syndrome (ARDS) caused by coronavirus disease (COVID-19). Important factors for COVID-19 mortality are diabetes status and elevated fasting plasma glucose (FPG). However, the effect of glycaemic variability on survival has not been explored in patients with COVID-19 and ARDS. This single-centre cohort study compared several metrics of glycaemic variability for goodness-of-fit in patients requiring mechanical ventilation due to COVID-19 ARDS in the ICU at University Hospital Aachen, Germany. 106 patients had moderate to severe ARDS (P/F ratio median [IQR]: 112 [87–148] mmHg). Continuous HRs showed a proportional increase in mortality risk with daily glycaemic variability (DGV). Multivariable unadjusted and adjusted Cox-models showed a statistically significant difference in mortality for DGV (HR: 1.02, (P) < 0.001, LR(P) < 0.001; HR: 1.016, (P) = 0.001, LR(P) < 0.001, respectively). Kaplan–Meier estimators yielded a shorter median survival (25 vs. 87 days) and a higher likelihood of death (75% vs. 31%) in patients with DGV ≥ 25.5 mg/dl (P < 0.0001). High glycaemic variability during ICU admission is associated with significant increase in all-cause mortality for patients admitted with COVID-19 ARDS to the ICU. This effect persisted even after adjustment for clinically predetermined confounders, including diabetes, median procalcitonin and FPG.

Plasma Levels and Renal Handling of Amino Acids Contribute to Determination of Risk of Mortality or Feed of Ventilation in Patients with COVID-19

COVID-19 infection may lead to serious complications, e.g., need for mechanical ventilation or death in some cases. A retrospective analysis of patients referred to our COVID Emergency Department, indiscriminately, was performed. A routine lab analysis measured amino acids in plasma and urine of patients. Data of surviving and deceased patients and those requiring or not requiring mechanical ventilation were compared, and logistic regression analyses have been performed. Deceased patients were older, had higher blood glucose, potassium, AST, LDH, troponin, d-dimer, hsCRP, procalcitonin, interleukin-6 levels (p < 0.05 for all). They had lower plasma serine, glycine, threonine, tryptophan levels (p < 0.01), higher tyrosine and phenylalanine levels (p < 0.05), and higher fractional excretion of arginine, methionine, and proline (p < 0.05) than survivors. In a regression model, age, severity score of COVID-pneumonia, plasma levels of threonine and phenylalanine were predictors of in-hospital mortality. There was a difference in ventilated vs. non-ventilated patients in CT-scores, glucose, and renal function (p < 0.001). Using logistic regression, CT-score, troponin, plasma level, and fractional excretion of glycine were predictors of ventilation. Plasma levels and renal excretion of certain amino acids are associated with the outcome of COVID-19 infection beside other parameters such as the CT-score or age.

Type 2 Diabetes Contributes to Altered Adaptive Immune Responses and Vascular Inflammation in Patients With SARS-CoV-2 Infection

SARS-CoV-2, which initially emerged in November of 2019, wreaked havoc across the globe by leading to clinical acute respiratory distress syndrome and continues to evade current therapies today due to mutating strains. Diabetes mellitus is considered an important risk factor for progression to severe COVID disease and death, therefore additional research is warranted in this group. Individuals with diabetes at baseline have an underlying inflammatory state with elevated levels of pro-inflammatory cytokines and lower levels of anti-inflammatory cytokines, both of which cause these individuals to have higher susceptibility to SARS- CoV2 infection. The detrimental effects of SARS-CoV-2 has been attributed to its ability to induce a vast cell mediated immune response leading to a surge in the levels of pro-inflammatory cytokines. This paper will be exploring the underlying mechanisms and pathophysiology in individuals with diabetes and insulin resistance making them more prone to have worse outcomes after SARS- CoV2 infection, and to propose an adjunctive therapy to help combat the cytokine surge seen in COVID-19. It will also look at the immunomodulatory effects of glutathione, an antioxidant shown to reduce immune dysregulation in other diseases; Vitamin D, which has been shown to prevent COVID-19 patients from requiring more intensive care time possibly due to its ability to decrease the expression of certain pro-inflammatory cytokines; and steroids, which have been used as immune modulators despite their ability to exacerbate hyperglycemia.

The Role of Diabetes and Hyperglycemia on COVID-19 Infection Course-A Narrative Review

It was previously reported that subjects with diabetes mellitus (DM) are more vulnerable to several bacterial or viral infections. In the era of coronavirus disease 2019 (COVID-19) pandemic, it is reasonable to wonder whether DM is a risk factor for COVID-19 infection, too. It is not yet clear whether DM increases the risk for contracting COVID-19 infection or not. However, patients with DM when infected are more likely to develop severe or even fatal COVID-19 disease course than patients without DM. Certain characteristics of DM patients may also deteriorate prognosis. On the other hand, hyperglycemia per se is related to unfavorable outcomes, and the risk may be higher for COVID-19 subjects without pre-existing DM. In addition, individuals with DM may experience prolonged symptoms, need readmission, or develop complications such as mucormycosis long after recovery from COVID-19; close follow-up is hence necessary in some selected cases. We here present a narrative review of the literature in order to set light into the relationship between COVID-19 infection and DM/hyperglycemia.

SIT1 transporter as a potential novel target in treatment of COVID-19

Studies published earlier this year demonstrated the association of the solute carrier SLC6A20 gene with the risk and severity of COVID-19. The SLC6A20 protein product (Sodium-dependent Imino Transporter 1 (SIT1)) is involved in the transport of amino acids, including glycine. Here we summarized the results of recent studies demonstrating the interaction of SIT1 with the ACE2 receptor for SARS-CoV-2 as well as an observed association of SLC6A20 with the risk and traits of Type 2 diabetes (T2D). Recently, it was also proposed that SLC6A20 represents the novel regulator of glycine levels and that glycine has beneficial effects against the proinflammatory cytokine secretion induced by SARS-CoV-2 infection. Ivermectin, as a partial agonist of glycine-gated chloride channels, was also recently suggested to interfere with the COVID-19 cytokine storm by inducing the activation of glycine receptors. Furthermore, plasma glycine levels are found to be decreased in diabetic patients. Thus, further clinical trials are warranted to confirm the potential favorable effects of targeting the SIT1 transporter and glycine levels in the treatment of COVID-19, particularly for the severe case of disease associated with hyperglycemia, inflammation, and T2D. These findings suggest that SIT1 may potentially represent one of the missing pieces in the complex puzzle observed between these two pandemic diseases and the potential novel target for their efficient treatment.