Association Between Triglyceride-glucose Index and Carotid Atherosclerosis in Patients with Systemic Lupus Erythematosus: A Cohort-based Study

Background:

Individuals with systemic lupus erythematosus (SLE) patients confer substantial increased risks of cardiovascular complications that have become the primary cause of premature mortality worldwide. We aimed to investigate the association between triglyceride-glucose (TyG) index and carotid atherosclerosis in patients with systemic lupus erythematosus (SLE).

Methods:

This cross-sectional study in a tertiary hospital included 333 consecutive SLE patients receiving carotid ultrasonography with integrated TyG index, calculated as ln [fasting triglycerides (mg/dL) × fasting glucose (mg/dL)/2]. The subjects were categorized into three groups according to the TyG index tertiles. Logistic regression models were used to assess the association of TyG index with carotid atherosclerosis and carotid artery plaque. Fully adjusted model included age, gender, body mass index, comorbidities, low-density lipoprotein cholesterol and SLE-related variables.

Results:

There were 10.5% (35/333) of participants identified as having carotid atherosclerosis. Patients with carotid atherosclerosis had significantly higher TyG index as compared with those without (8.77 ± 0.45 vs. 8.45 ± 0.49, p $<$ 0.001). The frequency of carotid atherosclerosis was increased with increases in TyG index tertiles (3.6% for tertile 1, 10.0% for tertile 2, 17.7% for tertile 3; p = 0.003). Multivariate logistic analyses showed that each 1-unit increase in TyG index was significantly associated with prevalent carotid atherosclerosis (unadjusted OR 4.07 (1.87-8.87); fully-adjusted OR 4.88 (1.74-13.69)). The unadjusted and fully-adjusted OR for occurrence of carotid atherosclerosis were 5.70 (1.88-17.28) and 5.88 (1.66-20.74) in patients with tertile 3 compared to patients with tertile 1 of TyG index (P for trend 0.006 and 0.019, respectively). Similar findings were noticeable for the outcome of carotid artery plaque.

Conclusions:

The present study suggested that an elevated TyG index was associated with a higher risk of carotid atherosclerosis, independent of traditional cardiovascular risk factors and SLE-related factors. TyG index may be a promising and accessible atherosclerotic indictor for SLE population.