Peripheral blood indicators and COVID-19: an observational and bidirectional Mendelian randomization study

BMC Med Genomics. 2024 Mar 28;17(1):81. doi: 10.1186/s12920-024-01844-4.

Abstract

Blood is critical for health, supporting key functions like immunity and oxygen transport. While studies have found links between common blood clinical indicators and COVID-19, they cannot provide causal inference due to residual confounding and reverse causality. To identify indicators affecting COVID-19, we analyzed clinical data (n = 2,293, aged 18-65 years) from Guangzhou Medical University's first affiliated hospital (2022-present), identifying 34 significant indicators differentiating COVID-19 patients from healthy controls. Utilizing bidirectional Mendelian randomization analyses, integrating data from over 2.46 million participants from various large-scale studies, we established causal links for six blood indicators with COVID-19 risk, five of which is consistent with our observational findings. Specifically, elevated Troponin I and Platelet Distribution Width levels are linked with increased COVID-19 susceptibility, whereas higher Hematocrit, Hemoglobin, and Neutrophil counts confer a protective effect. Reverse MR analysis confirmed four blood biomarkers influenced by COVID-19, aligning with our observational data for three of them. Notably, COVID-19 exhibited a positive causal relationship with Troponin I (Tnl) and Serum Amyloid Protein A, while a negative association was observed with Plateletcrit. These findings may help identify high-risk individuals and provide further direction on the management of COVID-19.

Keywords: Body fluids; COVID-19; Clinical indicators; Mendelian randomization.

Publication types

  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • COVID-19*
  • Genome-Wide Association Study
  • Humans
  • Mendelian Randomization Analysis*
  • Troponin I

Substances

  • Troponin I