The association of triglyceride-glucose index with cancer incidence and mortality: a systematic review and meta-analysis of cohort studies.

PURPOSE: This study seeks to summarize the relationship between the triglyceride-glucose (TyG) index, a novel and reliable surrogate indicator of insulin resistance, and cancer-associated outcomes through meta-analysis. METHODS: A thorough search was performed in PubMed, Embase, and Web of Science to identify cohort studies examining the relationship between the TyG index and cancer-associated outcomes. Adjusted hazard ratios (HR) with their 95% confidence intervals (CI) were pooled through random-effect meta-analyses. HRs were calculated using the TyG index as a continuous variable and as a categorial variable. RESULTS: Twenty-two studies were included in this systematic review. Meta-analysis of seven studies comparing the highest TyG group to the lowest TyG group showed a significantly increased risk of cancer in the former group (HR = 1.16, 95% CI 1.08-1.25). The same result was found when pooling the HRs from studies analyzing the TyG index as a continuous variable (HR = 1.08, 95% CI 1.05-1.11). The pooled results of two studies identified a significant association between the TyG index and cancer-related mortality among cancer-diagnosed people (HR = 1.21, 95% CI 1.06-1.39). Additionally, studies observed no association between the TyG index and cancer-related mortality among cancer-free people (HR = 1.02, 95% CI 0.93-1.12), as well as all-cause mortality in cancer patients (HR = 0.98, 95% CI 0.58-1.64). CONCLUSION: Our findings indicate that a higher TyG index is associated with an increased risk of cancer, but shows no significant overall association with cancer prognosis. Further investigation is essential to substantiate these associations and evaluate the clinical value of the TyG index. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/, identifier PROSPERO (420251014091).