Role of laboratory biomarkers in assessing the severity of COVID-19 disease. A cross-sectional study

Sex differences in D-dimer and critical illness in patients with COVID-19: A systematic review and meta-analysis

Background

Observed sex differences in COVID-19 outcomes suggest that men are more likely to experience critical illness and mortality. Thrombosis is common in severe COVID-19, and D-dimer is a significant marker for COVID-19 severity and mortality. It is unclear whether D-dimer levels differ between men and women, and the effect of D-dimer levels on disease outcomes remains under investigation.

Objectives

We aimed to evaluate the sex difference in the D-dimer level among hospitalized patients with COVID-19 and the effect of sex and D-dimer level on disease outcomes.

Methods

We meta-analyzed articles reporting D-dimer levels in men and women hospitalized for COVID-19, until October 2021, using random effects. Primary outcomes were mortality, critical illness, and thrombotic complications.

Results

In total, 11,682 patients from 10 studies were analyzed (N = 5606 men (55.7%), N = 5176 women (44.3%)). Men had significantly higher odds of experiencing mortality (odds ratios (OR) = 1.41, 95% CI: [1.25, 1.59], P ≤ .001, I² = 0%) and critical illness (OR = 1.76, 95% CI: [1.43, 2.18], P ≤ .001, I² = 61%). The mean D-dimer level was not significantly different between men and women (MD = 0.08, 95% CI: [-0.23, 0.40], P = .61, I² = 52%). In the subgroup analysis, men had significantly higher odds of experiencing critical illness compared with women in both the "higher" (P = .006) and "lower" (P = .001) D-dimer subgroups.

Conclusion

Men have significantly increased odds of experiencing poor COVID-19 outcomes compared with women. No sex difference was found in the D-dimer level between men and women with COVID-19. The diversity in D-dimer reporting impacts data interpretation and requires further attention.

The Associations of Iron Related Biomarkers with Risk, Clinical Severity and Mortality in SARS-CoV-2 Patients: A Meta-Analysis

The coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is spreading rapidly around the world and has led to millions of infections and deaths. Growing evidence indicates that iron metabolism is associated with COVID-19 progression, and iron-related biomarkers have great potential for detecting these diseases. However, the results of previous studies are conflicting, and there is not consistent numerical magnitude relationship between those biomarkers and COVID-19. Thereby, we aimed to integrate the results of current studies and to further explore their relationships through a meta-analysis. We searched peer-reviewed literature in PubMed, Scopus and Web of Science up to 31 May 2022. A random effects model was used for pooling standard mean difference (SMD) and the calculation of the corresponding 95% confidence interval (CI). I2 was used to evaluate heterogeneity among studies. A total of 72 eligible articles were included in the meta-analysis. It was found that the ferritin levels of patients increased with the severity of the disease, whereas their serum iron levels and hemoglobin levels showed opposite trends. In addition, non-survivors had higher ferritin levels (SMD (95%CI): 1.121 (0.854, 1.388); Z = 8.22 p for Z < 0.001; I2 = 95.7%, p for I2 < 0.001), lower serum iron levels (SMD (95%CI): −0.483 (−0.597, −0.368), Z = 8.27, p for Z < 0.001; I2 = 0.9%, p for I2 =0.423) and significantly lower TIBC levels (SMD (95%CI): −0.612 (−0.900, −0.324), Z = 4.16, p for Z < 0.001; I2 = 71%, p for I2 = 0.016) than survivors. This meta-analysis demonstrates that ferritin, serum iron, hemoglobin and total iron banding capacity (TIBC) levels are strongly associated with the risk, severity and mortality of COVID-19, providing strong evidence for their potential in predicting disease occurrence and progression.

Identification of hematological and inflammatory parameters associated with disease severity in hospitalized patients of COVID-19

Background and Objectives

India has emerged as the second worst hit nation by the Coronavirus pandemic in terms of total number of cases. Our data on hematological and inflammatory markers associated with COVID-19 is very limited. This study was conducted to assess the utility of various biomarkers in identifying severe disease.

Materials and Methods

All confirmed cases of COVID-19 admitted in our tertiary care centre from 1st March 2021 to 31st March 2021 were enrolled in the study. They were categorized into severe and non-severe disease categories based on pre-decided criteria. Their complete blood count parameters, D-dimer levels, serum C-reactive protein (CRP), ferritin and Lactate dehydrogenase (LDH) values were retrieved.

Statistical Analysis

All parameters were expressed as Mean ± Standard deviation for the two groups of patients. Student's t-test was used to test significance of the above markers between severe and non- severe disease. (P value < 0.05 was taken as statistically significant).

Results

A total of 150 COVID RT-PCR positive patients were evaluated. The patients with higher Absolute Neutrophil Count (ANC), Neutrophil to lymphocyte Ratio (NLR), Platelet to lymphocyte ratio (PLR), D-dimer levels and raised serum CRP, LDH, ferritin along with lymphocytopenia were associated with severe disease (P < 0.05). Hemoglobin, total leucocyte count and platelet count showed no correlation with disease severity.

Conclusion

These biomarkers associated with disease severity especially NLR, PLR, D-dimer and serum CRP levels could be used to triage patients at the time of admission thereby identifying those requiring intensive care and enabling optimal resource utilization.