A higher TyG index level is more likely to have enhanced incidence of T2DM and HTN comorbidity in elderly Chinese people: a prospective observational study from the reaction study

Background Triglyceride glucose index (TyG index) was related with both type 2 diabetes (T2DM) and hypertension (HTN). Prospective studies linking the TyG index to the incidence of T2DM and HTN comorbidity remain unclear. This study aimed to to explore the longitudinal association between TyG and new-onset T2DM with HTN. Methods 4,434 subjects (1249 males and 3185 females) without initial T2DM and HTN were followed up for 7 years. This study was conducted from November 2011 to August 2018 in the Gucheng, Laoshan and Jinding communities of Beijing. The incidence of T2DM with HTN during the 7-year follow-up was identified as the endpoint. The TyG index was divided into four quartiles: the < 25% level, the 25–50% level, the 50–75% level and the ≥ 75% level. The relationships between the TyG index and T2DM with HTN were evaluated by Cox proportional hazards regression models. Results During 7 years, the augmented trend of T2DM with HTN was observed in the participants. After adjusting for all confounding factors, compared with those in the lowest quartile of TyG index, the population in the highest quartile of TyG index had a higher risk of T2DM with HTN (hazard ratio (HR), 2.878; 95% confidence intervals (95% CI), 1.230–6.731, P = 0.015), however, the association remained significant only in the female population (HR 2.753, 95% CI, 1.061–7.139, p = 0.037). The TyG had superior predictive ability of increased risk of T2DM with HTN for the populations of older age (≥ 65 years) (HR 2.694, 95% CI 1.212–5.989, p = 0.015), higher eGFR (≥ 90 mL/(min·1.73 m 2 )) (HR 2.603, 95% CI 1.164–5.818, p = 0.020) or obesity (BMI ≥ 28 kg/m 2 ) (HR 2.547, 95% CI 1.001–6.478, p = 0.020). Conclusion A population with a higher TyG index level was more likely to have an enhanced incidence of T2DM and HTN comorbidity. TyG index could have the significance of clinical in early protection against T2DM with HTN.