Association between a body shape index and the risk of carotid atherosclerosis in the population from China’s Guanzhong Region

Carotid atherosclerosis (CAS) serves as a significant risk factor for stroke and is associated with obesity, especially visceral fat. A body shape index (ABSI) provides a more precise measurement of visceral fat accumulation, which is a simple and low-cost marker for ischemic stroke. Whether the ABSI predicts cervical arterial atherosclerosis remains uncertain. This study aimed to investigate the relationship between the ABSI and CAS. This cross - sectional study was carried out among residents aged 40 years and above in the general population of Guanzhong Plain. Following in-person interviews, all participants filled out a comprehensive questionnaire, provided blood samples, and additionally underwent cervical artery ultrasonography. The ABSI was calculated using a well-established formula and analyzed in quartiles (Q1-Q4). The logistic regression was used to investigate the relationship between the ABSI and CAS. Furthermore, restricted cubic spline curves (RCS) and subgroup analyses were also conducted. The receiver operating characteristic curve (ROC) was employed to compare the diagnostic performance of ABSI, Body Mass Index (BMI) and waist circumference (WC). A total of 4881 participants aged ≥ 40 years were finally included, with 68.47% comprising the CAS population. After fully adjustment, the odds ratios (Odds Ratios [OR], 95% CI) in the highest quartile group of the ABSI were 1.79 (1.47,2.19) compared to the lowest quartile group. RCS analysis indicated a nonlinear correlation between ABSI and CAS ( P for nonlinear < 0.001). Subgroup analysis indicated a notable interaction in hypertension subgroups (interaction p = 0.032). Additionally, ROC analysis indicated that ABSI achieved an AUC of 0.604, which was modestly higher than WC (AUC = 0.581) and BMI (AUC = 0.506). ABSI are correlated with an augmented risk of CAS among middle-aged and elderly Chinese adults, particularly among those with hypertension. ABSI may serve as a complementary anthropometric screening indicator for CAS, offering modest but consistent improvement over BMI and WC as a population-level risk stratification tool.