Association between lipid comprehensive index and carotid atherosclerosis: evidence from a large-scale ultrasound screening program

Carotid atherosclerosis (CA) has not been well characterized in relation to the Lipid Comprehensive Index (LCI) in middle-aged and elderly populations. This large-sample study aimed to examine the association between LCI and prevalent CA. This cross-sectional study analyzed data from 56,383 participants aged ≥ 40 years enrolled in the 2017–2020 Hubei Stroke Screening and Prevention Project. All participants underwent carotid ultrasonography for the evaluation of CA. LCI was calculated as [TC × TG × LDL-C/HDL-C]. Logistic regression and restricted cubic spline (RCS) modeling analyses were performed to examine the association of LCI, treated as both a continuous variable and quartiles, with CA. Subgroup analyses were conducted to explore effect modifications across various population characteristics. Logistic regression analysis showed that higher LCI levels were significantly associated with greater odds of CA, carotid intima-media thickening (CMT), plaque, and stenosis (all p trend < 0.001). Compared with the lowest quartile of LCI, the highest quartile had increased odds ratios (ORs) for CA, CMT, plaque, and stenosis, with ORs of 1.918 (1.751–2.201), 1.950 (1.749–2.174), 1.641 (1.487–1.812), and 1.531 (1.203–1.947), respectively. Additionally, per one-standard-deviation increase in LCI, the adjusted ORs for CA, CMT, plaque, and stenosis were 1.020 (1.017–1.022), 1.020 (1.017–1.022), 1.017 (1.014–1.019), and 1.011 (1.005–1.017), respectively. Subgroup analyses further indicated that the positive association between LCI and CA was generally consistent across most subgroups (all p trend < 0.001; p interaction > 0.05 for most subgroups). In populations aged ≥ 40 years, LCI shows a significant positive association with prevalent CA, suggesting that LCI may be a useful marker for assessing atherosclerosis risk.