Associations between the METS-IR index and cognitive function in community-dwelling Chinese middle-aged and older adult individuals: a cross-sectional study

作者：Nian Jiang, Chunyan Ma, Zhenning Feng, Yongjun Tang, Xiaolong Chen, Yao He, Weiyi Pang · 发表于：Frontiers in Public Health · 年份：2025 · DOI：10.3389/fpubh.2025.1607228 · 被引用次数：3 · 研究领域：Nutritional Studies and Diet、Dementia and Cognitive Impairment Research、Diabetes, Cardiovascular Risks, and Lipoproteins

Objective The relationship between insulin resistance and cognitive function has long been a subject of interest, but the association between the metabolic syndrome-insulin resistance (METS-IR) index and cognitive impairment remains unclear. Methods We utilized data from the 2015 China Health and Retirement Longitudinal Study (CHARLS) national survey, which, after screening, included a final sample of 12,307 participants. Cognitive function was assessed through face–to–face interviews via the MMSE scale. Multivariate logistic regression was used to evaluate the correlation between the METS-IR index and cognitive impairment. Using regression analysis results from fully adjusted models, we subsequently explored the nonlinear relationship between the METS-IR index and cognitive impairment via smooth curve fitting with constrained cubic splines and sought potential inflection points. Additionally, we executed a battery of sensitivity and subgroup analyses to validate the robustness of our findings. Results The study included 12,307 participants, of whom 49.02% were aged 45–60 years and 52.89% were female. The results revealed that for each unit increase in the METS-IR index, the risk of cognitive impairment increased by 1.4% ( OR = 1.014, 95% CI : 1.004–1.023; p < 0.01). When the METS-IR index was used as a categorical variable, compared with Q1, the odds of cognitive impairment increased by 17.1, 38.7, and 49.5% for each unit increase in the METS-IR index in the Q2, Q3, a...