Prognostic Value of Platelet to Lymphocyte Ratio in Sepsis: A Systematic Review and Meta-analysis

Abstract

The goal of this study was to conduct a systematic review of the literature on the relationship between peripheral blood platelet to lymphocyte ratio (PLR) and mortality in sepsis and to integrate the findings in a meta-analysis. An electronic search of three main databases was performed: PubMed, Embase, and Scopus on 19 December 2021. Finally, 16 studies comprising 2403 septic patients, including 1249 survivors and 1154 nonsurvivors, were included in this meta-analysis. We found that PLR levels were significantly higher in nonsurvivors than in survivors (random effect model: $\text{SMD}=0.72$ , 95% CI; 0.35–1.10, $p<0.001$ ). However, significant heterogeneity was observed across the studies ( $I^2=94.1\%$ , $p<0.01$ ). So, we used random effect model in our meta-analysis. In the subgroup analysis, according to mortality time, patients deceased during one month after sepsis had elevated levels of PLR compared to survivors ( $\text{SMD}=1.03$ , 95% $\text{CI}=0.15$ -1.92, $p=0.22$ ). However, in-hospital mortality was not associated with PLR level ( $\text{SMD}=0.41$ , 95% $\text{CI}=-0.18$ -0.99, $p=0.175$ ). Our findings support PLR to be a promising biomarker that can be readily integrated into clinical settings to aid in the prediction and prevention of sepsis mortality.