Background. The chronic inflammatory immune response is a significant factor in the pathogenesis of benign gynecological diseases. The systemic immunoinflammatory index (SII) and the platelet-to-lymphocyte ratio (PLR) are commonly available biomarkers of inflammation. However, evidence of the relationship between SII and PLR in patients with adenomyosis is limited. This study aimed to investigate the relationship between SII and PLR in patients with adenomyosis. Methods. This cross-sectional study included 483 patients with adenomyosis who were first diagnosed at our institution between January 2019 and December 2021. Basic patient clinical information and inflammatory factors were collected for univariate analysis, smoothed curve fitting, and multivariate segmented linear regression. Results. The results of the univariate analysis showed a significant positive correlation between PLR levels and SII (). In addition, a nonlinear relationship between PLR and SII was tested using a smoothed curve fit after adjusting for potential confounders. Multiple segmented linear regression models showed a significant relationship between SII and PLR in both SII < 1,326.47 (β 0.14, 95% CI: 0.12, 0.16; ) and >1,326.47 (β 0.02, 95% CI: −0.01, 0.05; P = 0.2461). Conclusions. In conclusion, this study showed a nonlinear relationship between SII and PLR in patients with uterine adenomyosis. An increase in serum PLR levels correlates with an increase in SII before SII levels reach an inflection point.

中文翻译：

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子宫腺肌症患者全身免疫炎症指数与血小板淋巴细胞比值的相关性

背景。慢性炎症免疫反应是妇科良性疾病发病的重要因素。全身免疫炎症指数（SII）和血小板与淋巴细胞比率（PLR）是常用的炎症生物标志物。然而，子宫腺肌症患者 SII 和 PLR 之间关系的证据有限。本研究旨在探讨子宫腺肌症患者SII与PLR的关系。方法。本横断面研究纳入2019年1月至2021年12月期间在我院首次诊断的483例子宫腺肌病患者。收集患者基本临床信息和炎症因子进行单因素分析、平滑曲线拟合和多元分段线性回归。结果。单变量分析结果显示PLR水平与SII之间呈显着正相关（）。此外，在调整潜在混杂因素后，使用平滑曲线拟合测试了 PLR 和 SII 之间的非线性关系。多元分段线性回归模型显示 SII 和 PLR 之间存在显着相关性，SII < 1,326.47（ β 0.14，95% CI：0.12，0.16；）和 >1,326.47（ β 0.02，95% CI：-0.01，0.05； P  = 0.2461）。结论。总之，本研究表明子宫腺肌症患者的 SII 和 PLR 之间存在非线性关系。在 SII 水平达到拐点之前，血清 PLR 水平的升高与 SII 的升高相关。