The impact of platelet-to-lymphocyte ratio on clinical outcomes in heart failure: a systematic review and meta-analysis

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.

Neutrophil to lymphocyte ratio (NLR) prognostic effects on heart failure; a systematic review and meta-analysis

BACKGROUND

Neutrophil to lymphocyte ratio (NLR), as a recent inflammatory index, has been reported to be a prognostic tool in different diseases. However, implication of this ratio in heart failure (HF) is less investigated. In this systematic review and meta-analysis, we aimed to assess the potential impact of NLR on HF clinical outcomes.

METHODS

Relevant English published records in PubMed, Scopus, Embase, and Web of Science were screened up to July 2023. Articles reporting clinical outcomes (follow-up or in-hospital mortality, readmission, HF prediction, extended hospital stay length, pulmonary vascular resistance, atrial fibrillation, renal disease and functional capacity) in HF sufferers were collected for further analysis with addition of NLR difference stratified by death/survived and HF status.

RESULTS

Thirty-six articles (n = 18231) were finally selected which reported NLR in HF sufferers (mean: 4.38, 95% confidence interval (CI): 4.02-4.73). We found 25 articles reported NLR and total mortality (either follow-up death (N = 19): 4.52 (95% CI: 4.03-5.01) or in-hospital death (N = 10): 5.33 (95% CI: 4.08-6.57)) with mean NLR of 4.74 (95% CI: 4.28-5.20). NLR was higher among deceased patients compared to survived ones (standard mean difference: 0.67 (95% CI: 0.48-0.87), P < 0.001)). NLR was found to be related with higher mortality risk (continuous variable: hazard ratio (HR): 1.12, 95% CI: 1.02-1.23, P = 0.013), categorical variable: HR: 1.77, 95% CI: 1.27-2.46, P = 0.001, T2 vs. T1: HR:1.56, 95%CI: 1.21-2.00, P = 0.001, T3 vs. T1: HR:2.49, 95%CI: 1.85-3.35, P < 0.001). Other aforementioned variables were not feasible to analyze due to presence of few studies.

CONCLUSIONS

NLR is a simple and acceptable prognostic tool for risk stratification and prioritizing high risk patients in clinical settings, especially in resource limited nations.

Prognostic impact of monocyte-to-lymphocyte ratio in coronary heart disease: a systematic review and meta-analysis

OBJECTIVE

Inflammatory biomarkers are novel tools to assess the prognosis of different cardiovascular diseases. We evaluated the impact of the monocyte-to-lymphocyte ratio (MLR) on clinical outcomes in patients with coronary heart disease (CHD).

METHODS

We systematically screened English-language articles in PubMed, Scopus, and Web of Science to 31 August 2022. Relevant articles reporting the MLR and its association with clinical outcomes (major adverse cardiovascular events (MACE), coronary artery disease (CAD) severity, mortality, cardiac rupture, subclinical CAD, acute coronary syndrome (ACS) prediction, thin-cap fibroatheroma, no-reflow phenomenon, MLR-related differences in percutaneous coronary intervention, heart failure hospitalization, and depression) in patients with CHD were collected for further analysis.

RESULTS

Nineteen articles were selected. The mean MLR was 0.34. A higher MLR was significantly associated with an increased risk of MACE among patients with CHD. The MLR was an independent predictor of MACE in patients with ACS. No significant association was found for CAD severity. A complementary analysis was not performed because of few studies focusing on the other predefined endpoints.

CONCLUSIONS

The MLR is a simple and widely available tool to predict MACE in patients with CHD. This biomarker can be utilized in emergency settings to prioritize high-risk patients and optimize therapeutic interventions.

Human catalase gene polymorphism (CAT C-262T) and risk of male infertility

Infertility is the failure of a couple to engender after endeavouring at least one full year of unprotected intercourse. It has been reported that reactive oxygen species contributed to pathogenesis of various disease. To inactivate ROS cells biosynthesise several antioxidant enzymes, one of them is catalase which contributes H2 O2 to H2 O and O2 . This study set out to delineate the association of catalase C-262T polymorphism with idiopathic male infertility. The study included 195 men with idiopathic infertility and 190 healthy volunteers. Genomic DNA was extracted from peripheral blood leucocytes. Genotype and allele frequencies were determined in patients and controls using allele-specific PCR (AS-PCR). The prevalence of genotype frequencies of the CAT CC/CT/TT was 31.79%, 65.12% and 3.07%, respectively, in infertile subjects, as against 24.73%, 55.26% and 20%, respectively, in healthy volunteers. Statistical analysis has emerged significant difference from the comparison of either genotype (P < 0.05). Taking into accounts of results, the catalase C-262T polymorphism indicates that CAT-262T/T genotype confers less susceptibility to male infertility. Further studies with larger numbers of patients are required for further evaluation and confirmation of our finding.