目的 本研究旨在探讨甘油三酯-葡萄糖（TyG）指数、胆固醇-高密度脂蛋白-葡萄糖（CHG）指数和血浆致动脉粥样硬化指数（AIP）在中国上海老年人超重与2型糖尿病（T2DM）关联中的中介作用。

方法 共纳入上海市慢性非传染性疾病管理队列中44,715名年龄≥60岁的参与者。超重定义为身体质量指数（BMI）≥24 kg/m²。T2DM由临床医生依据诊断标准确诊。采用中介分析分别估计直接效应、间接效应和总效应。

结果 参与者平均年龄为77±6.8岁，16,835例（37.65%）确诊为T2DM，27,880例（62.35%）未患病。在协变量校正模型中，超重老年人患T2DM的比值较非超重老年人高26%。TyG、CHG和AIP指数均与T2DM相关。中介分析显示，TyG、CHG和AIP指数所中介的总效应比例分别为22.03%、32.24%和6.47%。

结论 所检测的脂质-葡萄糖代谢指标，尤其是CHG和TyG指数，部分中介了超重与T2DM之间的关联。这些生物标志物可作为预防超重老年人发生T2DM的早期干预靶点。

Objective: This study aimed to explore the mediating roles of the triglyceride-glucose (TyG) index, cholesterol-HDL-glucose (CHG) index, and atherogenic index of plasma (AIP) in the association between overweight and type 2 diabetes mellitus (T2DM) among older adults in Shanghai, China.

Methods: A total of 44,715 participants aged ≥60 years from the Shanghai Non-communicable Diseases Management Cohort were included. Overweight was defined as a body mass index (BMI) ≥24 kg/m². T2DM was diagnosed clinically by physicians. Mediation analysis was performed to estimate direct, indirect, and total effects.

Results: The mean age of the participants was 77 ± 6.8 years, 16,835 (37.65%) were diagnosed with T2DM, and 27,880 (62.35%) did not. In covariate-adjusted models, overweight older adults had a 26% higher odds of T2DM than non-overweight older adults. The TyG, CHG, and AIP indices were all associated with T2DM. In the mediation analysis, the proportions of the total effect mediated by the TyG, CHG, and AIP indices were 22.03%, 32.24%, and 6.47%, respectively.

Conclusion: The lipid-glucose metabolic indices examined, particularly CHG and TyG indices, partially mediated the association between overweight and T2DM. These biomarkers may serve as early intervention targets to prevent T2DM among overweight older adults.