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.