Zhang Bin, Lai Junxing, Li Dan, Li Yongfeng, Wang Peng, Cai Shangan, Ren Qiang, Li Dong
Department of Hypertension and Vascular Disease, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
Department of Cardiovascular Disease and Clinical Experimental Center, Jiangmen Central Hospital, Jiangmen, China.
Front Cardiovasc Med. 2025 Apr 9;12:1583614. doi: 10.3389/fcvm.2025.1583614. eCollection 2025.
The triglyceride-glucose (TyG) index has been linked to impaired cardiovascular fitness (CVF). However, the available evidence regarding the direct relationship between the TyG index and maximal oxygen uptake (VOmax) is limited. This study aims to investigate the association between the TyG index and VOmax.
We conducted a retrospective cross-sectional study involving 3,571 participants who completed a CVF examination as part of the National Health and Nutrition Examination Survey (NHANES) 1999-2004. Data on triglycerides, glucose, and VOmax were collected from all participants. The TyG index was calculated using the formula: Ln[triglyceride (TG)(mg/dl) × fasting plasma glucose (FPG)(mg/dl)/2]. Linear regression analysis was utilized to substantiate the research objectives.
The complex sampling design and mobile examination center sample weights were considered. In multivariable linear regression analyses, each 1 unit increase in the TyG index was associated with a decrease in VOmax [ = -1.24, 95% CI (-1.97, -0.51), = 0.002] when expressed as a continuous variable, independent of confounders. The TyG index was converted into a categorical variable based on four quartiles. Compared with the lowest TyG quintile (Q1: 6.750-7.887), the fully adjusted for Q4 (8.672-12.481) was -1.91 (95% CI: -3.24, -0.57, < 0.007). A significant interaction ( = 0.007) between sex and the TyG index for VOmax was found in the population using subgroup analysis. The results of the sensitivity analysis remained stable. Mediation analysis showed the direct effect of the TyG index was -1.467 (-2.019, -0.948), with a total effect of -1.813 (-2.377, -1.286). The mediation effect of diastolic blood pressure (DBP), white blood cell count (WBC), and C-reactive protein (CRP) was -0.389 (-0.526, -0.268), -0.308 (-0.432, -0.177), and -0.252 (-0.453, -0.135), respectively. HGB was found to exert a suppressing effect on the relationship between the TyG index and VOmax, with a value of 1.469 (1.252, 1.702). The -values for all the above effects were <0.05.
In the US young and middle-aged population, the TyG index was significantly adversely associated with VOmax levels. Females may exert an interaction on TyG. Evidence supported DBP, WBC, and CRP as intervening variables through which the TyG index exerts its influence on VOmax. HGB may overrule the potential inverse association between the TyG index and VOmax.: Protocol #98-12.
甘油三酯-葡萄糖（TyG）指数与心血管健康状况受损（CVF）有关。然而，关于TyG指数与最大摄氧量（VOmax）之间直接关系的现有证据有限。本研究旨在探讨TyG指数与VOmax之间的关联。
我们进行了一项回顾性横断面研究，纳入了3571名参与者，他们作为1999 - 2004年国家健康与营养检查调查（NHANES）的一部分完成了心血管健康检查。收集了所有参与者的甘油三酯、血糖和VOmax数据。TyG指数使用公式计算：Ln[甘油三酯（TG）（mg/dl）×空腹血糖（FPG）（mg/dl）/2]。采用线性回归分析来证实研究目标。
考虑了复杂抽样设计和移动检查中心样本权重。在多变量线性回归分析中，当将TyG指数作为连续变量表示时，每增加1个单位，VOmax就会降低[β = -1.24，95%可信区间（-1.97，-0.51），P = 0.002]，且不受混杂因素影响。根据四分位数将TyG指数转换为分类变量。与最低的TyG五分位数（Q1：6.750 - 7.887）相比，Q4（8.672 - 12.481）的完全调整β为 -1.91（95%可信区间：-3.24，-0.57，P < 0.007）。通过亚组分析发现，在该人群中，性别与TyG指数对VOmax存在显著交互作用（P = 0.007）。敏感性分析结果保持稳定。中介分析显示，TyG指数的直接效应为 -1.467（-2.019，-0.948），总效应为 -1.813（-2.377，-1.286）。舒张压（DBP）、白细胞计数（WBC）和C反应蛋白（CRP）的中介效应分别为 -0.389（-0.526，-0.268）、-0.308（-0.432，-0.177）和 -0.252（-0.453，-0.135）。发现血红蛋白（HGB）对TyG指数与VOmax之间的关系有抑制作用，值为1.469（1.252，1.702）。上述所有效应的P值均<0.05。
在美国年轻和中年人群中，TyG指数与VOmax水平显著负相关。女性可能对TyG有交互作用。有证据支持DBP、WBC和CRP作为TyG指数影响VOmax的中介变量。HGB可能会推翻TyG指数与VOmax之间潜在的负相关关系。方案编号：98 - 12。
