Unveiling glycaemic variability patterns linked to the triglyceride-glucose index in type 2 diabetes: Insights from continuous glucose monitoring.

BACKGROUND

To investigate the triglyceride-glucose index (TyG) as a predictor of glycaemic variability phenotypes in patients with type 2 diabetes mellitus (T2DM) using continuous glucose monitoring (CGM)-derived metrics, guiding personalized management.

MATERIALS AND

METHODS

This cross-sectional study analysed 279 T2DM patients who underwent 14-day CGM monitering from community hospitals in Ningbo, China. Participants were stratified by TyG tertiles. Spectral clustering with complexity-invariant dynamic time warping identified distinct glycaemic variability glucotypes. Comprehensive CGM metrics spanning time-domain, frequency-domain, event-based, and circadian rhythm domains were evaluated. Multivariable logistic regression assessed associations between TyG and glycaemic phenotypes.

RESULTS

Across TyG tertiles, we observed progressive increases in HbA1c (6.8 ± 1.5%, 7.2 ± 1.2%, 7.3 ± 1.3%, p = 0.011), fasting glucose (6.1 ± 1.1, 7.2 ± 1.6, 8.5 ± 2.8 mmol/L, p < 0.001), and triglycerides (0.9 ± 0.2, 1.4 ± 0.4, 2.7 ± 1.0 mmol/L, p < 0.001). Most notably, patients in the highest TyG tertile exhibited sustained hyperglycaemia with lower TIR (81.8% to 72.8 to 70.3%, p = 0.001), elevated TAR (15.9% vs. 29.1%, p < 0.001), and paradoxically reduced TBR (2.3% to 1.4% to 0.6%, p = 0.014) and CV (26.2% to 25.8% to 23.8%, p = 0.021). Frequency domain analysis demonstrated that elevated TyG was associated with high-level, low-frequency glucose oscillations. Higher TyG tertiles demonstrated increased prevalence of severe variability glucotype (32.3% to 53.8% to 63.4%), with TyG emerging as the strongest independent predictor (OR = 1.87, 95% CI: 1.42-2.50, p < 0.001).

CONCLUSIONS

Elevated TyG identifies a distinct glycaemic phenotype characterized by high-level, low-frequency oscillations, sustained hyperglycaemia, and minimal hypoglycaemic risk. T2DM patients with high TyG levels may be appropriate candidates for more intensified glucose-lowering strategies.