Association of Triglyceride Glucose Index with Prevalence and Incidence of Diabetic Retinopathy in a Singaporean Population

OBJECTIVE: To examine the association of triglyceride glucose (TyG) index (product of fasting triglyceride and glucose) with prevalence and incidence of diabetic retinopathy (DR) in type 2 diabetes. METHODS: 1339 patients from an ongoing Singapore Study of Macro-angiopathy and Micro-Vascular Reactivity in Type 2 Diabetes (SMART2D) were included in this study. Fasting triglyceride and glucose levels were quantified and color fundus photographs were assessed for DR presence and severity. Logistic regression models were used to evaluate associations of TyG index with DR prevalence and incidence (median follow-up period = 3.2 years). RESULTS: Mean TyG index was higher in patients with DR than no DR (9.24±0.7 versus 9.04± 0.6, p<0.001). TyG index was significantly associated with DR prevalence (OR=1.4, CI 1.1–1.7, p=0.002) and incidence (OR=1.8, CI 1.04–2.9, p=0.03), after adjusting for confounders. In a stratified analysis, the association between TyG index and DR prevalence reached significance only in the subgroup with HbA1c levels < 7.0% (OR=2, CI 1.1–3.8, p=0.03). TyG index significantly predicted DR prevalence and incidence with area under receiver operating curve as 0.77 (CI 0.74–0.80, p <0.001) and 0.66 (CI 0.57–0.76, p value <0.01), respectively. CONCLUSION: TyG index is a good predictor for DR prevalence and incidence. It can also be a secondary treatment target for patients with optimally controlled levels of HbA1c.