Abstract
BACKGROUND: Insulin resistance (IR) may play a crucial role in irritable bowel syndrome (IBS) pathogenesis. However, it remains unclear whether triglyceride-glucose (TyG)-related indices, useful biomarkers for assessing IR, are associated with IBS development. OBJECTIVES: To investigated the link between baseline TyG-related indices and incident IBS. DESIGN: A prospective, population-based cohort study. METHODS: Participants free of IBS with available TyG-related indices (TyG-waist circumference (TyG-WC), TyG-waist-to-height ratio (TyG-WHtR), and TyG-body mass index (TyG-BMI)) at enrollment were included (N = 356,904). Primary endpoint was incident IBS. Cox regression was used to evaluate the association between TyG-related indices and IBS. RESULTS: During a median 14.6 years of follow-up (5,023,899 person-years), 7381 (2.1%) participants developed IBS. The mean (standard deviation) level of baseline TyG index was 8.7(0.6), with 8.0 (0.2), 8.5 (0.1), 8.9 (0.1), and 9.5 (0.3) in quartile 1-4. Compared with the lowest quartile, the highest quartile of all TyG-related indices was significantly associated with greater risk of incident IBS (TyG hazard ratio (HR) = 1.24, 95% confidence interval (CI): 1.16-1.33, <0.001; TyG-WC HR = 1.25, 95% CI: 1.16-1.34, <0.001; TyG-WHtR HR = 1.24, 95% CI: 1.16-1.33, <0.001; TyG-BMI HR = 1.15, 95% CI: 1.07-1.23, <0.001). Meanwhile, per standardized deviation increment of TyG-related indices were also associated with 6%-9% greater risk of IBS (TyG HR = 1.09, 95% CI: 1.07-1.12; TyG-WC HR = 1.09, 95% CI: 1.07-1.12; TyG-WHtR HR = 1.09, 95% CI: 1.06-1.11; TyG-BMI HR = 1.06, 95% CI: 1.03-1.08). Similar results were observed in various sensitivity analyses and subgroup analysis. CONCLUSION: Higher TyG-related indices are linked to higher risk of incident IBS, highlighting the importance of IR in IBS pathogenesis.