Abstract Body (Do not enter title and authors here): Background:
Cardiovascular disease remains the leading cause of morbidity and mortality among individuals with type 1 diabetes mellitus (T1DM). Insulin resistance, increasingly recognized in this population, contributes significantly to cardiovascular risk. The estimated glucose disposal rate (eGDR), a non-invasive surrogate for insulin sensitivity, has emerged as a potential predictor of adverse cardiovascular outcomes in T1DM.
Research Question:
This study aimed to assess the association between eGDR and the risk of major adverse cardiovascular events, coronary artery disease, and all-cause mortality in individuals with T1DM.
Methods:
We conducted a systematic review and meta-analysis in accordance with PRISMA guidelines. PubMed, Embase, Scopus, and Cochrane Library were searched through March 6, 2025. Eligible studies reported multivariable-adjusted risk estimates evaluating the association between eGDR and cardiovascular outcomes. Pooled hazard ratios (HRs) were calculated using random-effects models with Paule–Mandel variance estimation and Knapp–Hartung adjustment. Subgroup and meta-regression analyses assessed potential effect modifiers.
Results:
Sixteen studies involving 29,075 individuals with T1DM were included. Higher eGDR was associated with significantly lower risk of major cardiovascular events (HR per unit increase: 0.79; 95% confidence interval: 0.72–0.87; heterogeneity: I² = 63%) and all-cause mortality (HR: 0.84; 95% confidence interval: 0.82–0.86; I² = 0%). Participants with lower eGDR also had a markedly higher risk of coronary artery disease (HR for low vs. high eGDR: 3.61; 95% confidence interval: 2.83–4.62; I² = 0%). Subgroup analyses revealed stronger inverse associations in older individuals (≥40 years), those with body mass index <25 kg/m², and those with diabetes duration ≥20 years. Meta-regression did not identify any statistically significant effect modifiers.
Conclusion:
Lower eGDR is consistently associated with increased risks of major adverse cardiovascular events, coronary artery disease, and all-cause mortality in individuals with T1DM. These findings support the utility of eGDR as a practical, non-invasive marker for cardiovascular risk stratification in this high-risk population.