Triglyceride glucose-body mass index and the risk of progression to diabetes from prediabetes: A 5-year cohort study in Chinese adults

Abstract

Objective: Evidence regarding the relationship between the triglyceride glucose-body mass index (TyG-BMI) and the risk of progression from prediabetes to diabetes remains limited. Our study aimed to investigate the relationship between them in patients with prediabetes.

Methods: In this retrospective cohort study, data were collected from 25,279 patients with prediabetes who received health checks between 2010 and 2016. We used a Cox proportional-hazards regression model to examine the relationship between TyG-BMI and diabetes risk. We used Cox proportional hazards regression with cubic spline functions and smooth curve fitting to identify the nonlinear relationship between them. In addition, A series of sensitivity and subgroup analyses were also conducted.

Results: The mean age of the included participants was 49.29 ± 13.82 years old, and 1,6734 (66.2%) were male. The mean TyG-BMI was 219.47. The median follow-up time was 2.89 years, and 2,687 (10.63%) individuals had a final diagnosis of diabetes. After adjusting for covariates, TyG-BMI was positively linked with incident diabetes in patients with prediabetes (HR = 1.011, 95%CI 1.010-1.012). TyG-BMI had a non-linear connection with diabetes risk, and its inflection point was 231.66. Right and left effects sizes (HR) at the inflection point were 1.017 (95%CI:1.014-1.019) and 1.007 (95%CI:1.005-1.009), respectively. The sensitivity analysis demonstrated the robustness of these results.

Conclusion: This study demonstrated a positive, non-linear relationship between the TyG-BMI and diabetes risk in Chinese patients with prediabetes. When the TyG-BMI was <231.66, there was a significant positive association between TyG-BMI and the risk of progression from prediabetes to diabetes. This study serves as a reference to promote clinical consultation and optimize diabetes prevention decisions for patients with prediabetes.

Keywords: diabetes; non-linear relationship; prediabetes; smooth curve fitting; triglyceride-glucose index.

Figure 1

Flowchart of study participants.

Figure 2

Distribution of TyG-BMI. It presented a normal distribution, ranging from 116.94 to 334.08, with a mean of 219.47.

Figure 3

The incidence rate for diabetes according to the quartiles of TyG-BMI. Participants with the highest TyG-BMI(Q4) had higher diabetes incidence rates than those with the lowest TyG-BMI(Q1) (p < 0.001 for trend).

Figure 4

The incidence of diabetes in prediabetic patients of age stratification by 10 intervals. It shows that the incidence of diabetes in participants with prediabetes was higher in men than in women, regardless of age group. It was also found that the incidence of diabetes increased with age in both men and women.

Figure 5

Kaplan–Meier event-free survival curve. Kaplan–Meier event-free survival curve. The probability of diabetes-free survival differed significantly between the TyG-BMI quartiles (log-rank test, p < 0.001). The probability of diabetes-free survival gradually decreased with increasing TyG-BMI, suggesting that the group with the highest TyG-BMI had the highest risk of diabetes.

Figure 6

The non-linear relationship between TyG-BMI and the risk of diabetes in prediabetic patients. We used a Cox proportional hazards regression model with cubic spline functions to evaluate the relationship between the TyG-BMI and diabetes risk. The result showed that the relationship between the TyG-BMI and diabetes risk in prediabetic patients was non-linear, with the inflection point of the TyG-BMI ratio being 231.66.

Figure 7

The results of ROC curve analysis for measuring the ability of TyG-BMI, BMI, TG, TyG, and TG/HDL-c ratio to predict the risk of diabetes.