目的：探讨失眠障碍患者外周淋巴细胞亚群特征及其与认知功能的关系。方法：纳入2022年4月～ 2023年3月武汉市第一医院未服药失眠障碍患者39例（病例组）及健康对照51例（对照组）。采用蒙特利 尔认知评估量表（montreal cognitive assessment，MoCA）及Stroop色词测验评估认知功能；并检测2组外周 淋巴细胞亚群的比例与绝对计数。通过组间比较、相关分析及多因素线性回归分析评估外周淋巴细胞亚 群与认知功能的关联。结果：与对照组相比，病例组 MoCA 总分及其多个认知域评分均显著降低（P＜ 0.05）；Stroop色词测验正确率降低，且Stroop-D反应时间延长（P＜0.05）。病例组T细胞、辅助性T淋巴细 胞（Th 细胞）、B 细胞、T+B+NK 细胞比例及绝对计数显著增加（P＜0.05），NK 细胞比例显著降低（P= 0.001）。进一步的相关性分析表明MoCA总分及部分认知域评分与Th细胞、B细胞比例及绝对计数呈负 相关（P＜0.05），与NK细胞比例呈正相关（P＜0.05）；Stroop-D、Stroop-C的正确率和反应时间与T细胞、Th 细胞指标存在相关性（P＜0.05）。多因素线性回归分析显示校正年龄、受教育程度和身体质量指数后，Th 细胞占比和绝对计数、Th/细胞毒性T淋巴细胞（CTL）比值、B细胞绝对计数、NK细胞占比及T+B+NK总绝 对计数与MoCA总分呈独立相关（P＜0.05）。结论：失眠障碍患者存在以执行功能受损为主的轻度多认知 域认知损害，并伴随外周免疫谱向适应性免疫偏移。这种外周淋巴细胞亚群失衡变化与认知功能下降显 著相关，可能为失眠相关认知损害的潜在生物标志物。

To investigate the characteristics of peripheral lymphocyte subsets in patients with insomnia disorder (ID) and their associations with cognitive function. Methods: A total of 39 drug-naïve patients with ID and 51 healthy controls (HCs) were recruited from Wuhan First Hospital between April 2022 and March 2023. Cognitive function was assessed using the Montreal Cognitive Assessment (MoCA) and the Stroop Color-Word Test. Flow cytometry was performed to determine the proportions and absolute counts of peripheral lymphocyte subsets in both groups. Between-group comparisons, correlation analyses, and multivariable linear regression analyses were conducted to evaluate the relationships between peripheral lymphocyte subsets and cognitive function. Results: Compared with HCs, the ID group had significantly lower MoCA total scores and poorer performance in multiple cognitive domains (P<0.05). In the Stroop test, the ID group showed reduced accuracy and prolonged Stroop-D reaction time (P<0.05). In addition, the ID group exhibited significantly increased proportions and absolute counts of T cells, helper T lymphocytes (Th cells), B cells, and total T+B+NK cells (P<0.05), whereas the proportion of NK cells was significantly decreased (P= 0.001). Correlation analyses further showed that the MoCA total score and several domain scores were negatively correlated with the proportions and absolute counts of Th cells and B cells (P<0.05), but positively correlated with the proportion of NK cells (P<0.05). Moreover, the accuracy and reaction time in Stroop-C and Stroop-D were significantly correlated with T-cell- and Th-cell-related parameters (P<0.05). Multivariable linear regression analysis showed that, after adjustment for age, education level, and BMI, Th-cell proportion, Th-cell absolute count, the Th/cytotoxic T lymphocyte (CTL) ratio, B-cell absolute count, NK-cell proportion, and total T+B+NK absolute count were independently associated with the MoCA total score. Conclusion: Patients with ID showed mild multidomain cognitive impairment, predominantly involving executive function, accompanied by a peripheral immune profile characterized by adaptive immune predominance. This imbalance in peripheral lymphocyte subsets was significantly associated with cognitive decline and may represent a potential biomarker of insomnia-related cognitive impairment.