Association between immune-inflammation index and the risk of gout attack: a systematic review and meta-analysis

Background: Evidence shows that gout attack is closely related to immune and inflammatory levels. However, there are limited evidence-based results for immune-inflammatory indices to predict gout attacks. Objectives: This study aimed to explore the predictive value of immune-inflammation index for acute gout. Design: Systematic review and meta-analysis. Data sources and methods: . Literature screening and data extraction were performed independently by two investigators, and standardized mean difference (SMD) and 95% confidence interval (95% CI) were used to evaluate the differences in inflammatory indexes between gout patients and individuals in the healthy control group. A random-effects model was used to analyze the predictive value of different inflammatory indexes for acute gout patients. In addition, sensitivity analysis and subgroup analysis were also conducted to explore the sources of heterogeneity. Results: A total of 8 articles involving 2655 participants were included in this meta-analysis. The findings showed that both neutrophil-to-lymphocyte ratio (NLR; SMD: 0.75; 95% CI: 0.48-1.03) and platelet-lymphocyte ratio (PLR; SMD: 0.52; 95% CI: 0.24-0.79) showed significant value in predicting acute gout attacks. The sensitivity analysis results showed that both NLR and PLR were significantly stable in predicting acute gout attacks. Meanwhile, subgroup analyses were performed based on region, sample size, and age. The results showed that the predictive value of NLR and PLR for acute gout was significant in all subgroups, and age and sample size were potential sources of heterogeneity in PLR. However, no sources of heterogeneity were found in NLR. Conclusion: NLR and PLR are well-performed in predicting acute gout attacks. Given a lack of prospective studies, a limited number of related references, and significant heterogeneity, large-scale prospective studies are needed to verify the relationship between immune-inflammation index and gout attacks.