Dose–response association between the triglycerides: High‐density lipoprotein cholesterol ratio and type 2 diabetes mellitus risk: The rural Chinese cohort study and meta‐analysis

BACKGROUND: High triglyceride (TG) and low high-density lipoprotein cholesterol (HDL-C) levels are traditional risk factors for type 2 diabetes mellitus (T2DM). This study evaluated the dose-response relationship between the TG/HDL-C ratio and T2DM risk. METHODS: The study included 11 946 adults without baseline diabetes from the Rural Chinese Cohort Study. Cox proportional hazards regression was used to investigate the association between the TG/HDL-C ratio and T2DM. The dose-response relationship was evaluated by restricted cubic spline analysis. In addition, pooled odds ratios (OR) were calculated with a random-effects model in a meta-analysis including the present study and another three eligible articles. RESULTS: During 2007-14, 618 patients with T2DM were identified (9.68/1000 person-years). People in the highest TG/HDL-C ratio quartile had a higher T2DM risk than those in the lowest quartile (adjusted hazard ratio [aHR] 2.11, 95% confidence interval [CI] 1.55-2.86); however, the association between the TG/HDL-C ratio and T2DM was stronger in females than males (aHR 1.27 [95% CI 1.16-1.39; and 1.19 [95% CI 1.04-1.37], respectively). In body mass index-specific analysis, the association was stronger in normal weight than overweight/obese people. The dose-response meta-analysis showed that a 1-unit increment in the TG/HDL-C ratio increased the T2DM risk by 28% (95% CI 20%-36%), with a positive linear relationship (Plinear  = 0.326). CONCLUSIONS: The TG/HDL-C ratio was an independent risk factor of T2DM, especially in females, and linearly increased the risk of T2DM; thus, it may be a useful indicator to identify future T2DM.