Background: Inflammation has been suggested to play a role in heart failure (HF) pathogenesis. However, the role of platelet-to-lymphocyte ratio (PLR), as a novel biomarker, to assess HF prognosis needs to be investigated. We sought to evaluate the impact of PLR on HF clinical outcomes.
Methods: English-published records in PubMed/Medline, Scopus, and Web-of-science databases were screened until December 2023. Relevant articles evaluated PLR with clinical outcomes (including mortality, rehospitalization, HF worsening, and HF detection) were recruited, with PLR difference analysis based on death/survival status in total and HF with reduced ejection fraction (HFrEF) patients.
Results: In total, 21 articles (n = 13,924) were selected. The total mean age was 70.36 ± 12.88 years (males: 61.72%). Mean PLR was 165.54 [95% confidence interval (CI): 154.69-176.38]. In total, 18 articles (n = 10,084) reported mortality [either follow-up (PLR: 162.55, 95% CI: 149.35-175.75) or in-hospital (PLR: 192.83, 95% CI: 150.06-235.61) death rate] and the mean PLR was 166.68 (95% CI: 154.87-178.50). Further analysis revealed PLR was significantly lower in survived HF patients rather than deceased group (152.34, 95% CI: 134.01-170.68 versus 194.73, 95% CI: 175.60-213.85, standard mean difference: -0.592, 95% CI: -0.857 to -0.326, p < 0.001). A similar trend was observed for HFrEF patients. PLR failed to show any association with mortality risk (hazard ratio: 1.02, 95% CI: 0.99-1.05, p = 0.289). Analysis of other aforementioned outcomes was not possible due to the presence of few studies of interest.
Conclusion: PLR should be used with caution for prognosis assessment in HF sufferers and other studies are necessary to explore the exact association.
Keywords: heart failure; meta-analysis; mortality; platelet-to-lymphocyte ratio; prognosis; systematic review.
Platelet to lymphocyte ratio and heart failureInflammation plays a role in heart failure (HF), and a blood test called the platelet-to-lymphocyte ratio (PLR) might be helpful in predicting patients’ outcomes. We found that deceased HF patients had higher PLR values in comparison to those who survived, irrespective of cardiac pump function, with similar pattern for patients with decreased cardiac function (HF with reduced ejection fraction). However, this biomarker failed to show any significant association with death risk. In conclusion, PLR may have some potential to help predict HF prognosis, but it needs more research and physicians should probably be cautious about using PLR alone in clinical settings.