Laboratory markers associated with COVID-19 progression in patients with or without comorbidity: A retrospective study

FIB-4 Index Can Predict Mortality in Hospitalized Patients with COVID-19 Infection, Independent of CT Severity Score

BACKGROUND

The fibrosis 4 (FIB-4) index is typically used in assessing liver fibrosis, and has shown potential in predicting the outcome in various diseases. This study aims to evaluate the predictive power of the FIB-4 index for mortality in COVID-19 patients admitted to a reference hospital in Tehran, Iran.

METHODS

In this prospective cohort study, 387 patients with COVID-19 without diabetes, were categorized into deceased and surviving groups. We compared anthropometric and demographic data, liver function tests, CT scores, and FIB-4 indices between the groups. Multivariate logistic regression assessed the independent association of FIB-4 with mortality.

RESULTS

Among the 387 patients, (all non-diabetics), 58 (15%) died, with a higher mortality rate observed in patients with a FIB-4 index≥2.6 (63.4%) compared to those with FIB-4<2.6 (29.7%). Deceased patients were considerably older and more likely to be hypertensive (P values<0.001). After adjustment of confounding factors, a FIB-4 index≥2.6 was found to be independently associated with increased mortality (OR: 13.511, 95% CI: 1.356-134.580, P=0.026).

CONCLUSION

The FIB-4 index, calculable by routine laboratory tests, may be a valuable prognostic factor for COVID-19 mortality. This easily obtainable marker could help identify high-risk patients early, potentially allowing for more rapid intervention and treatment prioritization.

Lab results of COVID-19 patients: Omicron vs delta variants

BACKGROUND

The coronavirus disease 2019 (COVID-19) virus has been a world-known pandemic since February 2020. Multiple variances had been established; the most common variants in Israel were omicron and delta.

AIM

To analyze and compare laboratory values in the "omicron" and "delta" variants of the coronavirus by conducting follow-up examinations and laboratory audits on COVID-19 patients admitted to our institution.

METHODS

A retrospective study, two groups, 50 patients in each group. Patients examined positive for COVID-19 were divided into groups according to the common variant at the given time. We reviewed demographic data and laboratory results such as complete blood count and full chemistry, including electrolytes and coagulation parameters.

RESULTS

The mean age was 52%, 66.53 ± 21.7 were female. No significance was found comparing laboratory results in the following disciplines: Blood count, hemoglobin, and lymphocytes (P = 0.41, P = 0.87, P = 0.97). Omicron and delta variants have higher neutrophil counts, though they are not significantly different (P = 0.38). Coagulation tests: Activated paritial thromoplastin test and international normalized ratio (P = 0.72, P = 0.68). We found no significance of abnormality for all electrolytes.

CONCLUSION

The study compares laboratory results of blood tests between two variants of the COVID-19 virus - omicron and delta. We found no significance between the variants. Our results show the need for further research with larger data as well as the need to compare all COVID-19 variants.

Association between Fibrinogen-to-Albumin Ratio and Prognosis of Hospitalized Patients with COVID-19: A Systematic Review and Meta-Analysis

Although the fibrinogen-to-albumin ratio (F/R ratio) has been used as an inflammation marker to predict clinical outcomes in patients with cardiovascular diseases, its association with the prognosis of patients with coronavirus disease 2019 (COVID-19) remains unclear. Electronic databases including EMBASE, MEDLINE, Google Scholar, and Cochrane Library were searched from inception to 20 June 2022. The associations of F/R ratio with poor prognosis (defined as the occurrence of mortality or severe disease) were investigated in patients with COVID-19. A total of 10 studies (seven from Turkey, two from China, one from Croatia) involving 3675 patients published between 2020 and 2022 were eligible for quantitative syntheses. Merged results revealed a higher F/R ratio in the poor prognosis group (standardized mean difference: 0.529, p < 0.001, I2 = 84.8%, eight studies) than that in the good prognosis group. In addition, a high F/R ratio was associated with an increased risk of poor prognosis (odds ratio: 2.684, I2 = 59.5%, five studies). Pooled analysis showed a sensitivity of 0.75, specificity of 0.66, and area under curve of 0.77 for poor prognosis prediction. In conclusion, this meta-analysis revealed a positive correlation between F/A ratio and poor prognostic outcomes of COVID-19. Because of the limited number of studies included, further investigations are warranted to support our findings.

Prognostic value of elevated lactate dehydrogenase in patients with COVID-19: a systematic review and meta-analysis

PURPOSE

This meta-analysis aimed to evaluate the prognostic performance of elevated lactate dehydrogenase (LDH) in patients with COVID-19.

METHODS

A systematic literature search was performed using PubMed, Embase and EuropePMC on 19 November 2020. The outcome of interest was composite poor outcome, defined as a combined endpoint of mortality, severity, need for invasive mechanical ventilation and need for intensive care unit care. Severity followed the included studies' criteria.

RESULTS

There are 10 399 patients from 21 studies. Elevated LDH was present in 44% (34%-53%) of the patients. Meta-regression analysis showed that diabetes was correlated with elevated LDH (OR 1.01 (95% CI 1.00 to 1.02), p=0.038), but not age (p=0.710), male (p=0.068) and hypertension (p=0.969). Meta-analysis showed that elevated LDH was associated with composite poor outcome (OR 5.33 (95% CI 3.90 to 7.31), p<0.001; I2: 77.5%). Subgroup analysis showed that elevated LDH increased mortality (OR 4.22 (95% CI 2.49 to 7.14), p<0.001; I2: 89%). Elevated LDH has a sensitivity of 0.74 (95% CI 0.60 to 0.85), specificity of 0.69 (95% CI 0.58 to 0.78), positive likelihood ratio of 2.4 (95% CI 1.9 to 2.9), negative likelihood ratio of 0.38 (95% CI 0.26 to 0.55), diagnostic OR of 6 (95% CI 4 to 9) and area under curve of 0.77 (95% CI 0.73 to 0.80). Elevated LDH would indicate a 44% posterior probability and non-elevated LDH would in indicate 11% posterior probability for poor prognosis. Meta-regression analysis showed that age, male, hypertension and diabetes did not contribute to the heterogeneity of the analyses.

CONCLUSION

LDH was associated with poor prognosis in patients with COVID-19.

PROSPERO REGISTRATION NUMBER

CRD42020221594.

Heterogeneity and Risk of Bias in Studies Examining Risk Factors for Severe Illness and Death in COVID-19: A Systematic Review and Meta-Analysis

This systematic review and meta-analysis synthesized the evidence on the impacts of demographics and comorbidities on the clinical outcomes of COVID-19, as well as the sources of the heterogeneity and publication bias of the relevant studies. Two authors independently searched the literature from PubMed, Embase, Cochrane library, and CINAHL on 18 May 2021; removed duplicates; screened the titles, abstracts, and full texts by using criteria; and extracted data from the eligible articles. The variations among the studies were examined by using Cochrane, Q.; I2, and meta-regression. Out of 11,975 articles that were obtained from the databases and screened, 559 studies were abstracted, and then, where appropriate, were analyzed by meta-analysis (n = 542). COVID-19-related severe illness, admission to the ICU, and death were significantly correlated with comorbidities, male sex, and an age older than 60 or 65 years, although high heterogeneity was present in the pooled estimates. The study design, the study country, the sample size, and the year of publication contributed to this. There was publication bias among the studies that compared the odds of COVID-19-related deaths, severe illness, and admission to the ICU on the basis of the comorbidity status. While an older age and chronic diseases were shown to increase the risk of developing severe illness, admission to the ICU, and death among the COVID-19 patients in our analysis, a marked heterogeneity was present when linking the specific risks with the outcomes.

Meta-Analysis and Systematic Review of Coagulation Disbalances in COVID-19: 41 Studies and 17,601 Patients

Introduction

Coagulation parameters are important determinants for COVID-19 infection. We conducted meta-analysis to assess the association between early hemostatic parameters and infection severity.

Methods

Electronic search was made for papers that addressed clinical characteristics of COVID-19 patients and disease severity. Results were filtered using exclusion and inclusion criteria and then pooled into a meta-analysis to estimate the standardized mean difference (SMD) with 95% confidence interval (CI) for D-dimers, fibrinogen, prothrombin time, platelet count (PLT), activated partial thromboplastin time. To explore the heterogeneity and robustness of our fundings, sensitivity and subgroup analyses were conducted. Publication bias was assessed with contour-enhanced funnel plots and Egger's test by linear regression. Coagulation parameters data from retrospective cohort study of 451 patients with COVID-19 at National Research Center for Cardiac Surgery were included in meta-analysis of published studies.

Results

Overall, 41 original studies (17,601 patients) on SARS-CoV-2 were included. For the two groups of patients, stratified by severity, we identified that D-dimers, fibrinogen, activated partial thromboplastin time, and prothrombin time were significantly higher in the severe group [SMD 0.6985 with 95%CI (0.5155; 0.8815); SMD 0.661 with 95%CI (0.3387; 0.9833); SMD 0.2683 with 95%CI (0.1357; 0.4009); SMD 0.284 with 95%CI (0.1472; 0.4208)]. In contrast, PLT was significantly lower in patients with more severe cases of COVID-19 [SMD -0.1684 with 95%CI (-0.2826; -0.0542)]. Neither the analysis by the leave-one-out method nor the influence diagnostic have identified studies that solely cause significant change in the effect size estimates. Subgroup analysis showed no significant difference between articles originated from different countries but revealed that severity assessment criteria might have influence over estimated effect sizes for platelets and D-dimers. Contour-enhanced funnel plots and the Egger's test for D-dimers and fibrinogen revealed significant asymmetry that might be a sign of publication bias.

Conclusions

The hemostatic laboratory parameters, with exception of platelets, are significantly elevated in patients with severe COVID-19. The two variables with strongest association to disease severity were D-dimers and fibrinogen levels. Future research should aim outside conventional coagulation tests and include analysis of clotting formation and platelet/platelet progenitors characteristics.

Organ function biomarker abnormalities, associated factors and disease outcome among hospitalized patients with COVID-19

Background: The aim of this study was to determine the magnitude of abnormal organ function tests and biomarkers in hospitalized patients with confirmed COVID-19 and to define the association among markers of organ failure, disease severity and its outcome in hospitalized COVID-19 patients in Ethiopia. Methods: A prospective cohort study was conducted among COVID-19 patients admitted to Millennium COVID-19 Treatment Center from December 2020 to June 2021. Results: The median age of the 440 study participants was 60.3 ± 1.3 years, and from these 71.3% of patients were male. Disease severity: p-value: 0.032; adjusted odds ratio (AOR) (95% CI): 4.4 (0.022-0.085); and the presence of any co-morbidity; p-value: 0.012; AOR (95% CI): 0.80 (0.47-0.83) was significantly associated with mortality. Aspartate transaminase, alanine transaminase and alkaline phosphatase parameter values of patients overall, were elevated - mainly among critical patients (56.9 ± 57.7, 58.5 ± 63 and 114.6 ± 60, respectively).

Prevalence and Prognostic Importance of High Fibrosis-4 Index in COVID-19 Patients

INTRODUCTION

The fibrosis 4 (FIB-4) index was developed to predict advanced fibrosis in patients with liver disease. We aimed to evaluate the association of FIB-4 with risk factors for progression to critical illness in middle-aged patients hospitalized for coronavirus disease 2019 (COVID-19).

METHOD

We included patients aged 35-65 years who were hospitalized following a positive RT-PCR SARS-Cov-2 test in a tertiary hospital. All data were obtained from the medical records of the patients during the first admission to the hospital. The FIB-4 index was calculated according to the equation (age (years) x AST (IU/L)/platelet count (10⁹/L)/√ALT (IU/L)). The FIB-4 index was divided into three categories according to the score categorisation: <1.3 = low risk, 1.3-2.67 = moderate risk, and >2.67 = high risk.

RESULTS

A total of 619 confirmed COVID-19 patients (mean age = 52 yrs.) were included in this study; 37 (6.0%) were admitted to the intensive care unit (ICU), of which 44% were intubated and eight (1.3%) patients died during follow-up. The results of patients with high FIB-4 scores were compared with those with low FIB-4 scores. In patients with high FIB-4 scores, male gender, and advanced age, decreased neutrophil, lymphocyte, thrombocyte, and albumin counts, elevated AST, LDH, CK, ferritin, CRP, and D-dimer, and low GFR were the high-risk factors for critical illness. Additionally, the number of patients referred to ICU with high FIB-4 who died had higher scores than from those with low scores.

CONCLUSION

The FIB-4 index derived from baseline data obtained during hospitalisation can be used as a simple, inexpensive, and straightforward indicator to predict ICU requirement and/or death in middle-aged hospitalized COVID-19 patients.

A Simple Scoring Model Predicting the Outcome of COVID-19 Patients: Tanta COVID Score

BACKGROUND

COVID-19 is a worldwide pandemic with high rates of morbidity and mortality, and an uncertain prognosis leading to an increased risk of infection in health providers and limited hospital care capacities. In this study, we have proposed a predictive, interpretable prognosis scoring system with the use of readily obtained clinical, radiological and laboratory characteristics to accurately predict worsening of the condition and overall survival of patients with COVID-19.

METHODS

This is a single-center, observational, prospective, cohort study. A total of 347 patients infected with COVID-19 presenting to the Tanta University Hospital, Egypt, were enrolled in the study, and clinical, radiological and laboratory data were analyzed. Top-ranked variables were identified and selected to be integrated into a Cox regression model, building the scoring system for accurate prediction of the prognosis of patients with COVID-19.

RESULTS

The six variables that were finally selected in the scoring system were lymphopenia, serum CRP, ferritin, D-Dimer, radiological CT lung findings and associated chronic debilitating disease. The scoring system discriminated risk groups with either mild disease or severe illness characterized by respiratory distress (and also those with hypoxia and in need for oxygen therapy or mechanical ventilation) or death. The area under the curve to estimate the discrimination performance of the scoring system was more than 90%.

CONCLUSION

We proposed a simple and clinically useful predictive scoring model for COVID- 19 patients. However, additional independent validation will be required before the scoring model can be used commonly.

Predictive role of FAR ratio in COVID-19 patients

OBJECTIVE

No effective treatment has yet been found for SARS-Cov-2, which caused a pandemic outbreak in 2019. It is crucial to detect the progression of COVID-19 in patients as early as possible. Fibrinogen to albumin ratio (FAR) has been used as a new inflammatory marker. We aimed to find out whether the use of the FAR as a predictor of mortality in COVID-19 patients provides clinical benefit.

MATERIALS AND METHODS

Data from 590 patients with COVID-19 from March 15, 2020 to January 15, 2021 in medicine wards and intensive care units (ICU) were retrospectively analysed. Demographic data and other laboratory markers were collected from the electronic medical records. Relationship between FAR was investigated between patients in the survivor/non-survivor patients.

FINDINGS

The mean FAR levels in patients who were non-survivor was 24.44 ± 30.3 (n = 272 and 11.29 ± 6.29 (n = 275) (P = .000) in patients survivor COVID-19 infection. In ROC curve for FAR, the threshold FAR that may pose a risk for mortality was determined as 13.84 ((AUC: 0.808 (0.771-0.844)); 74.9% sensitivity, 74.6% specificity; P = .000)).

RESULT

As a result of this study, increased FAR were found to be important markers in determining the mortality levels in COVID-19 patients.

Temporal Associations of the SARS-CoV-2 NP Antigen and Anti-Spike Total Ig Levels with Laboratory Parameters in a Greek Cohort of Hospitalized COVID-19 Patients

Background

The direct effect of SARS-CoV-2 on the lungs results in increased hospitalization rates of patients with pneumonia. Severe COVID-19 patients often develop ARDS which is associated with poor prognosis. Assessing risk factors for COVID-19 severity is indispensable for implementing and evaluating therapeutic interventions. We investigated the temporal associations between the SARS-CoV-2 antigen (Ag), total Immunoglobulin (Ig) levels, and several laboratory parameters in hospitalized patients with varying degrees of COVID-19 severity.

Methods

The SARS-CoV-2 nucleocapsid protein (NP) and total Ig Spike (S) protein-specific antibodies were determined for each patient with lateral flow assays through repeated sampling every two days. Hematological and biochemical parameters were evaluated at the same time points.

Results

40 Greek COVID-19 patients (31 males, 9 females) with a median age of 59.50 ± 16.21 years were enrolled in the study. The median time from symptom onset to hospitalization was 8.0 ± 4.19 days. A significant negative correlation was observed between the SARS-CoV-2 Ag and total Ig levels. The temporal correlation patterns of the SARS-CoV-2 NP Ag and anti-S total Ig levels with laboratory markers varied among patients with differing degrees of COVID-19 severity. Severe-critical cases had lower SARS-CoV-2 Ag and increased total Ig levels as compared to mild-moderate cases.

Conclusions

Distinct temporal profiles of the SARS-CoV-2 NP Ag and anti-S total Ig levels may distinguish different groups of COVID-19 severity.

Tailoring glucocorticoids in patients with severe COVID-19: a narrative review

OBJECTIVE

To discuss the pathogenesis of severe coronavirus disease 2019 (COVID-19) infection and the pharmacological effects of glucocorticoids (GCs) toward this infection. To review randomized controlled trials (RCTs) using GCs to treat patients with severe COVID-19, and investigate whether GC timing, dosage, or duration affect clinical outcomes. Finally. to discuss the use of biological markers, respiratory parameters, and radiological evidence to select patients for improved GC therapeutic precision.

BACKGROUND

COVID-19 has become an unprecedented global challenge. As GCs have been used as key immunomodulators to treat inflammation-related diseases, they may play key roles in limiting disease progression by modulating immune responses, cytokine production, and endothelial function in patients with severe COVID-19, who often experience excessive cytokine production and endothelial and renin-angiotensin system (RAS) dysfunction. Current clinical trials have partially proven this efficacy, but GC timing, dosage, and duration vary greatly, with no unifying consensus, thereby creating confusion.

METHODS

Publications through March 2021 were retrieved from the Web of Science and PubMed. Results from cited references in published articles were also included.

CONCLUSIONS

GCs play key roles in treating severe COVID-19 infections. Pharmacologically, GCs could modulate immune cells, reduce cytokine and chemokine, and improve endothelial functions in patients with severe COVID-19. Benefits of GCs have been observed in multiple clinical trials, but the timing, dosage and duration vary across studies. Tapering as an option is not widely accepted. However, early initiation of treatment, a tailored dosage with appropriate tapering may be of particular importance, but evidence is inconclusive and more investigations are needed. Biological markers, respiratory parameters, and radiological evidence could also help select patients for specific tailored treatments.

The inflammatory markers of multisystem inflammatory syndrome in children (MIS-C) and adolescents associated with COVID-19: A meta-analysis

To conduct a systematic review and meta-analysis to characterize inflammatory markers in comparisons of multisystem inflammatory syndrome in children (MIS-C) versus severe/non-severe COVID-19, severe MIS-C versus non-severe MIS-C, and among age groups of MIS-C. Nine databases were searched for studies on inflammatory markers of MIS-C. After quality checks, data were pooled using a fixed or random effects model. Inflammatory markers included white blood cell count (WBC) or leukocytes, absolute lymphocyte count (ALC), absolute neutrophil count (ANC), platelet count (PLT), C-reactive protein (CRP), procalcitonin (PCT), ferritin, D-dimer, lactate dehydrogenase (LDH), fibrinogen, and erythrocyte sedimentation rate (ESR) for comparisons by severity and age. Twenty-one studies with 1735 participants yielded 787 MIS-C patients. Compared to non-severe COVID-19 patients, MIS-C patients had lower ALC and higher ANC, CRP, and D-dimer levels. Compared to severe COVID-19 patients, MIS-C patients had lower LDH and PLT counts and higher ESR levels. Severe MIS-C patients had higher levels of WBC, ANC, CRP, D-dimer, and ferritin than non-severe MIS-C patients. For MIS-C, younger children (0-5 years) had lower CRP and ferritin levels than middle-aged/older children/adolescents. Measurement of inflammatory markers might assist clinicians in accurate evaluation and diagnosis of MIS-C and the associated disorders.

Clinical and radiological characteristics of COVID‑19 patients without comorbidities : A single-center study

Objective

To evaluate the clinical characteristics and detailed imaging features in coronavirus disease 2019 (COVID-19) patients without comorbidities.

Material and methods

This retrospective study included laboratory-confirmed and symptomatic COVID-19 patients without comorbid diseases who were admitted to our second level hospital between March 2020 and September 2020. We assessed the clinical, biochemical and imaging diagnostic parameters on admission. The patients were classified as non-severe and progress to severe group and then the initial parameters were compared.

Results

We enrolled 135 adult COVID-19 patients, 12 progressed to severe disease during hospitalization. Compared to the non-severe group, patients who progressed to severe were older (p < 0.001) and were more likely to manifest coughing (p = 0.011) and have higher lactate dehydrogenase (LDH) levels (p = 0.011). On chest computed tomography (CT) images, multilobar (p = 0.016), peripherally (p = 0.001) distributed mixed ground glass opacities and consolidation (p < 0.001), crazy paving (p = 0.007) and higher total CT severity score (p < 0.001) were significantly associated with severe disease.

Conclusion

Knowledge of the clinical and radiological parameters associated with disease severity might be useful to guide clinical decision-making for COVID-19 patients without comorbidities.

Clinical Significance of Plasma D-Dimer in COVID-19 Mortality

It is not clear whether D-dimer can be an independent predictor of coronavirus disease 2019 (COVID-19) mortality, and the cut-off of D-dimer for clinical use remains to be determined. Therefore, a comprehensive analysis is still necessary to illuminate the clinical significance of plasma D-dimer in COVID-19 mortality. We searched PubMed, Embase, Cochrane Library, and Scopus databases until November 2020. STATA software was used for all the statistical analyses. The identifier of systematic review registration was PROSPERO CRD42020220927. A total of 66 studies involving 40,614 COVID-19 patients were included in our meta-analysis. Pooled data showed that patients in high D-dimer group had poor prognosis than those in low D-dimer group [OR = 4.52, 95% CI = (3.61, 5.67), P < 0.001; HR = 2.81, 95% CI = (1.85, 4.27), P < 0.001]. Sensitivity analysis, pooled data based on different effect models and the Duval and Tweedie trim-and-fill method did not change the conclusions. Subgroup analyses stratified by different countries, cutoffs, sample size, study design, and analysis of OR/HR still keep consistent conclusions. D-dimer was identified as an independent predictor for COVID-19 mortality. A series of values including 0.5 μg/ml, 1 μg/ml, and 2 μg/ml could be determined as cutoff of D-dimer for clinic use. Measurement and monitoring of D-dimer might assist clinicians to take immediate medical actions and predict the prognosis of COVID-19.

A Pandemic within Other Pandemics. When a Multiple Infection of a Host Occurs: SARS-CoV-2, HIV and Mycobacterium tuberculosis

By the middle of 2021, we are still immersed in the coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The concurrence of this new pandemic in regions where human immunodeficiency virus (HIV) and tuberculosis (TB) infections possess the same epidemiological consideration, has arisen concerns about the prognosis, clinical management, symptomatology, and treatment of patients with triple infection. At the same time, healthcare services previously devoted to diagnosis and treatment of TB and HIV are being jeopardized by the urgent need of resources and attention for COVID-19 patients. The aim of this review was to collect any article considering the three conditions (HIV, TB, and SARS-CoV-2), included in PubMed/Medline and published in the English language since the beginning of the COVID-19 pandemic. We focused on detailed descriptions of the unusual cases describing the three co-infections. Eighty-four out of 184 publications retrieved met our inclusion criteria, but only three of them reported cases (five in total) with the three concomitant infections. The clinical evolution, management, and therapy of all of them were not different from mild/severe cases with exclusive COVID-19; the outcome was not worse either, with recovery for the five patients. Cases of patients with COVID-19 besides HIV and TB infections are scarce in literature, but studies deliberately embracing the triple infection as a priori inclusion criterion should be carried out in order to provide a complete understanding of joint influence.

Serum Prealbumin Concentrations, COVID-19 Severity, and Mortality: A Systematic Review and Meta-Analysis

Excessive inflammation and malnutrition are associated with coronavirus disease 2019 (COVID-19) severity and mortality. Combined biomarkers of malnutrition and inflammation, such as serum prealbumin, might be particularly attractive for early risk stratification. We conducted a systematic review and meta-analysis of studies reporting serum prealbumin in patients with COVID-19. We searched PubMed, Web of Science and Scopus, between January and November 2020, for studies reporting data on serum prealbumin, COVID-19 severity, defined as severe illness, prolonged viral load, receiving mechanical ventilation or admitted to intensive care unit (ICU), and mortality. Nineteen studies in 4,616 COVID-19 patients were included in the meta-analysis. Pooled results showed that serum prealbumin concentrations were significantly lower in patients with severe disease and non-survivors (standard mean difference, SMD, −0.92, 95% CI, −1.10 to −0.74, P < 0.001). Extreme heterogeneity was observed (I² = 77.9%; P < 0.001). In sensitivity analysis, the effect size was not significantly affected when each study was in turn removed (range between −0.86 and −0.95). The Begg's (P = 0.06) and Egger's t-tests (P = 0.26) did not show publication bias. Pooled SMD values were significantly and negatively associated with age (t = −2.18, P = 0.045) and C-reactive protein (t = −3.85, P = 0.002). In our meta-analysis, lower serum prealbumin concentrations were significantly associated with COVID-19 severity and mortality. This combined marker of malnutrition and inflammation might assist with early risk stratification and management in this group.

Laboratory markers associated with COVID-19 progression in patients with or without comorbidity: A retrospective study

OBJECTIVES

To investigate laboratory markers for COVID-19 progression in patients with different medical conditions.

METHODS

We performed a multicenter retrospective study of 836 cases in Hubei. To avoid the collinearity among the indicators, principal component analysis (PCA) followed by partial least squares discriminant analysis (PLS-DA) was performed to obtain an overview of laboratory assessments. Multivariable logistic regression analysis and multivariable Cox proportional hazards regression analysis were respectively used to explore risk factors associated with disease severity and mortality. Survival analysis was performed in patients with the most common comorbidities.

RESULTS

Lactate dehydrogenase (LDH) and prealbumin were associated with disease severity in patients with or without comorbidities, indicated by both PCA/PLS-DA and multivariable logistic regression analysis. The mortality risk was associated with age, LDH, C-reactive protein (CRP), D-dimer, and lymphopenia in patients with comorbidities. CRP was a risk factor associated with short-term mortality in patients with hypertension, but not liver diseases; additionally, D-dimer was a risk factor for death in patients with liver diseases.

CONCLUSIONS

Lactate dehydrogenase was a reliable predictor associated with COVID-19 severity and mortality in patients with different medical conditions. Laboratory biomarkers for mortality risk were not identical in patients with comorbidities, suggesting multiple pathophysiological mechanisms following COVID-19 infection.