Increased insulin resistance is associated with vascular cognitive impairment in Chinese patients with cerebral small vessel disease

Background The aim of this study was to investigate the association between insulin resistance (IR) and vascular cognitive impairment (VCI) in patients with cerebral small vessel disease (CSVD). Methods A total of 275 CSVD patients were enrolled in this retrospective case-control study. The homeostatic model assessment of insulin resistance (HOMA-IR) was used to measure the index of insulin resistance. Cognitive function was assessed using the Montreal Cognitive Assessment (MoCA). Spearman's correlation coefficient was used to evaluate the correlation between HOMA-IR and MoCA score. The variance inflation factor (VIF) was used to detect collinearity between variables. Multivariate logistic regression analysis was employed to confirm whether HOMA-IR is an independent risk factor for VCI in CVSD. Finally, receiver operating characteristic (ROC) curve analysis was conducted to assess the diagnostic value of HOMA-IR in VCI. Results Of the 275 patients, 164 displayed VCI. VCI patients showed a significantly higher level of HOMA-IR compared to non-VCI patients (P < 0.001). HOMA-IR was negatively correlated with the MoCA score (r = -0.593, P < 0.001). After adjusting for potential confounding variables, using HOMA-IR quartile 1 (<1.11) as the reference, HOMA-IR quartile 3 (1.71-2.50) and quartile 4 (>= 2.50) were independently associated with the occurrence of VCI; for each one unit increase in the HOMA-IR, the risk of VCI increased by 177.3% (odds ratio 2.773, 95% confidence interval: 1.050-7.324, P = 0.040) and 444.3% (odds ratio 5.443, 95% confidence interval: 2.109-14.050, P < 0.001), respectively. According to the ROC curve, the optimal cut-off point of HOMA-IR in predicting VCI was 1.55, and the area under the curve was 0.744, with a sensitivity of 71.3% and a specificity of 69.4%. Conclusion This study demonstrated that increased IR is significantly associated with VCI in CSVD patients.