Obstructive sleep apnea syndrome (OSAS) patients have severe multisystem metabolic disorders in the body, with a high comorbidity rate with various metabolic diseases and poor prognosis. The adipokine Metrnl is a newly identified target for regulating lipid and glycolipid metabolism. The correlation of Metrnl with OSAS and OSAS-related metabolic disorders has been rarely reported.

To observe the differences of adipokine Metrnl in patients with OSAS, and explore its relationship with inflammation and insulin resistance caused by OSAS.

A total of 119 participants who were hospitalized and physically examined in the geriatric department of the First Affiliated Hospital of Baotou Medical College, Inner Mongolia University of Science and Technology from 2021 to 2022, were selected and divided into the mild OSAS group (n=57), moderate-to-severe OSAS group (n=26) and control group (n=62) according to the results of standard polysomnography monitoring. General data of the 3 groups was collected, including fasting blood glucose (FBG), fasting insulin (FINS), total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), glycosylated hemoglobin A_1c (HbA_1c), uric acid (UA), Metrnl, nuclear factor-κB (NF-κB), IL-6, TNF-α, IL-10 and IL-4 levels. The homeostatic model assessment for insulin resistance (HOMA-IR) was used to assess insulin resistance.

BMI in the moderate-to-severe OSAS group was higher than the control group and mild OSAS group (P<0.05) ; FINS level in the moderate-to-severe OSAS group was higher than the mild OSAS group and control group, and FINS level in the mild OSAS group was higher than the control group (P<0.05) ; Metrnl level of the moderate-to-severe OSAS group was lower than the mild OSAS group and control group, and Metrnl level in the mild OSAS group was lower than the control group (P<0.01) ; NF-κB, TNF-α, IL-6, and HOMA-IR in the OSAS group were higher than the control group, TNF-α and HOMA-IR in the moderate-to-severe OSAS group were higher than the mild OSAS group and control group, TNF-α and HOMA-IR in the mild OSAS group were higher than the control group (P<0.01), IL-10 in the OSAS group was lower than the control group (P<0.01). Partial correlation analysis showed that Metrnl level was negatively correlated with NF-κB (r=-0.30), IL-6 (r=-0.40), TNF-α (r=-0.37), HOMA-IR (r=-0.36), FBG (r=-0.32), HbA_1c (r=-0.33) and AHI (r=-0.51), and positively correlated with IL-10 (r=0.27) (P<0.05). Multiple linear regression analysis showed that IL-6, TNF-α, HOMA-IR were independent influencing factors for Metrnl level (P<0.05) .

The expression level of Metrnl is reduced in OSAS patients and negatively correlated with the severity of OSAS. HOMA-IR, IL-6, TNF-α are independent influencing factors for Metrnl level in OSAS patients.

阻塞性睡眠呼吸暂停综合征（OSAS）患者体内存在严重的多系统代谢紊乱，OSAS与多种代谢性疾病的共患病率高且预后差，脂肪因子Metrnl是新发现的调节脂质、糖脂代谢的靶点，Metrnl与OSAS及其所致代谢紊乱的关系鲜见报道。

观察OSAS患者体内脂肪因子Metrnl差异，探讨其与OSAS所致炎症和胰岛素抵抗的关系。

选取2021—2022年在内蒙古科技大学包头医学院第一附属医院老年科住院和体检的研究对象119例，依据标准多导睡眠监测结果分为轻度OSAS组31例，中重度OSAS组26例，对照组62例。收集3组研究对象的一般资料，测定其空腹血糖（FBG）、空腹胰岛素（FINS）、总胆固醇（TC）、三酰甘油（TG）、低密度脂蛋白胆固醇（LDL-C）、高密度脂蛋白胆固醇（HDL-C）、糖化血红蛋白（HbA_1c）、尿酸（UA）、Metrnl、核因子κB（NF-κB）、白介素（IL）-6、肿瘤坏死因子α（TNF-α）、IL-10、IL-4水平，采用稳态模型胰岛素抵抗指数（HOMA-IR）评估胰岛素抵抗。

中重度OSAS组BMI高于对照组、轻度OSAS组（P<0.05）；中重度OSAS组FINS高于轻度OSAS组、对照组，轻度OSAS组FINS高于对照组（P<0.05）；中重度OSAS组Metrnl水平低于轻度OSAS组、对照组，轻度OSAS组Metrnl水平低于对照组（P<0.01）；轻度OSAS组和中重度OSAS组NF-κB、TNF-α、IL-6、HOMA-IR高于对照组，中重度OSAS组TNF-α、HOMA-IR高于轻度OSAS组、对照组，轻度OSAS组TNF-α、HOMA-IR高于对照组（P<0.01）。轻度OSAS组和中重度OSAS组IL-10低于对照组（P<0.01）。偏相关分析结果显示Metrnl水平与NF-κB（r=-0.30）、IL-6（r=-0.40）、TNF-α（r=-0.37）、HOMA-IR（r=-0.36）、FBG（r=-0.32）、HbA_1c（r=-0.33）、AHI（r=-0.51）呈负相关，与IL-10（r=0.27）呈正相关（P<0.05）。多元线性回归显示IL-6、TNF-α、HOMA-IR是Metrnl水平的影响因素（P<0.05）。

OSAS患者的Metrnl水平降低，并与OSAS的严重程度呈负相关；HOMA-IR、IL-6、TNF-α是OSAS患者Metrnl水平的独立影响因素。