BackgroundThe triglyceride and glucose (TyG) index is associated with the risk of nonalcoholic fatty liver disease (NAFLD), but the dose−response relationship between them is still unknown. We conducted a comprehensive meta-analysis to study the dose−response association between the TyG index and the risk of NAFLD.MethodsWe systematically searched the Cochrane Library, PubMed, and Embase databases until July 2022 for relevant studies. The robust error meta-regression method was used to investigate the dose−response association between the TyG index and NAFLD. Summary relative risks (ORs) and 95% CIs were estimated by using a random-effects model.ResultsA total of 4 cohort and 8 cross-sectional studies were included, with 28,788 NAFLD cases among the 105,365 participants. A positive association for the risk of NAFLD was observed for each additional unit of the TyG index with a linear association (p=0.82), and the summary OR was 2.84 (95% CI, 2.01-4.01). In the subgroup analyses, a stronger association of the TyG index with NAFLD was shown in females than in males (men: OR=2.97, 95% CI 2.55-3.46, women: OR=4.80, 95% CI 3.90-5.90, Psubgroup<0.001).ConclusionThe TyG index may be a novel independent risk factor for NAFLD beyond traditional risk factors.Systematic Review Registrationhttps://www.crd.york.ac.uk/prospero, identifier (CRD42022347813).

Background The triglyceride and glucose (TyG) index has been linked to various cardiovascular diseases. However, it's still unclear whether the TyG index is associated with arterial stiffness and coronary artery calcification (CAC). Methods We conducted a systematic review and meta-analysis of relevant studies until September 2022 in the PubMed, Cochrane Library, and Embase databases. We used a random-effects model to calculate the pooled effect estimate and the robust error meta-regression method to summarize the exposure-effect relationship. Results Twenty-six observational studies involving 87,307 participants were included. In the category analysis, the TyG index was associated with the risk of arterial stiffness (odds ratio [OR]: 1.83; 95% CI 1.55–2.17, I2 = 68%) and CAC (OR: 1.66; 95% CI 1.51–1.82, I2 = 0). The per 1-unit increment in the TyG index was also associated with an increased risk of arterial stiffness (OR: 1.51, 95% CI 1.35–1.69, I2 = 82%) and CAC (OR: 1.73, 95% CI 1.36–2.20, I2 = 51%). Moreover, a higher TyG index was shown to be a risk factor for the progression of CAC (OR = 1.66, 95% CI 1.21–2.27, I2 = 0, in category analysis, OR = 1.47, 95% CI 1.29–1.68, I2 = 41% in continuity analysis). There was a positive nonlinear association between the TyG index and the risk of arterial stiffness (Pnonlinearity < 0.001). Conclusion An elevated TyG index is associated with an increased risk of arterial stiffness and CAC. Prospective studies are needed to assess causality. Graphical Abstract