AUTHOR=Cheng Yongqing , You Shuangfei , Wang Xin , Ge Yingchao , Li Lei , Ren Taojie , Chen Songjie , He Guojun , Xue Shouru TITLE=A high triglyceride-glucose index correlates with cognitive impairment in Parkinson’s disease: a cross-sectional study JOURNAL=Frontiers in Neuroscience VOLUME=Volume 19 - 2025 YEAR=2025 URL=https://www.frontiersin.org/journals/neuroscience/articles/10.3389/fnins.2025.1620118 DOI=10.3389/fnins.2025.1620118 ISSN=1662-453X ABSTRACT=BackgroundInsulin resistance (IR) is proved be involved in the pathophysiology of Parkinson’s disease (PD). As an effective surrogate marker of IR, the correlation between the triglyceride-glucose (TyG) index and PD remains unclear. This cross-sectional study aimed to explore the association between the TyG index and cognitive impairment in PD (PDCI).MethodsPatients with sporadic PD were consecutively enrolled between May 2022 and October 2023. The cognitive function was evaluated using the Montreal Cognitive Assessment (MoCA). The Spearman correlation analysis was used to evaluate the correlation between TyG index and MoCA score, Unified-Parkinson Disease Rating Scale (UPDRS) III and peripheral blood oxidative stress markers, respectively. Logistic regression analysis was performed to explore the correlation between TyG and PDCI and dementia in PD (PDD).ResultsA total of 78 patients were enrolled, of whom 50 (64.1%) were diagnosed with PDCI [26 with mild cognitive impairment (MCI) and 24 with PDD]. The TyG index in patients with dementia and MCI were higher than those with normal cognition (9.32 ± 0.43 vs. 8.90 ± 0.47 vs. 8.51 ± 0.46, P < 0.001). The Spearman correlation analysis demonstrated that TyG was negatively correlated with MoCA (r = −0.704, P < 0.001) and superoxide dismutase (r = −0.244, P = 0.031), but positively correlated with UPDRS III (r = 0.246, P = 0.030). Multivariate logistic regression analysis showed that TyG was independently associated with PDCI regardless of whether it was used as a continuous variable (OR = 6.177, 95% CI = 1.590–24.000) or a tertile variable (OR = 5.478, 95% CI = 1.030–29.132). This association persisted after excluding patients with diabetes. The receiver operating characteristic (ROC) analysis suggested that the area under the curve (AUC) of TyG for predicting PDCI was 0.805 (95% CI = 0.707–0.903, P < 0.001).ConclusionElevated TyG levels were associated with an increased likelihood of PDCI in patients with PD.