Background

Fasting proinsulin/fasting insulin, proinsulin/insulin, vitamin D3, and waistline are each associated with the risk of diabetes. The aim of this study was to explore the effects of fasting proinsulin/fasting insulin, proinsulin/insulin, vitamin D3, and waistline on diabetes prediction in the Chinese Han population.

Methods

Our study consisted of 490 subjects with glucose metabolism dysfunction (GMD) and 770 healthy subjects. Spearman’s correlation analysis was used to assess the relationship of clinical characteristics with prediabetes. Receiver operation characteristic (ROC) curve analysis was used to identify the diagnostics value in diagnosing prediabetes.

Results

Our study indicated that fasting proinsulin/fasting insulin, vitamin D3, and waistline were positively associated with prediabetes. Fasting proinsulin/fasting insulin (OR = 1.73, p = 0.002), vitamin D3 (OR = 1.02, p < 0.001), and waistline (OR = 1.04, p < 0.001) were significantly related to an increased risk of prediabetes. Stratified analyses results showed that fasting proinsulin/fasting insulin (odds ratio [OR] = 2.51, p = 0.001), vitamin D3 (OR = 1.02, p = 0.043), and waistline (OR = 1.03, p = 0.006) had a strong association with prediabetes in men, while only vitamin D3 (OR = 1.03, p < 0.001) and waistline (OR = 1.05, p < 0.001) were strongly related to prediabetes risk in women. ROC curve analysis results revealed that the area under the curve (0.936, p < 0.001) and sensitivity (100%) in combination of the fasting proinsulin/fasting insulin, proinsulin/true insulin, vitamin D3, and waistline provided a better diagnostic value of than either parameter alone.

Conclusion

The fasting proinsulin/fasting insulin, vitamin D3, and waistline showed a strong association with an increased risk of prediabetes. The combination of fasting proinsulin/ fasting insulin, proinsulin/true insulin, vitamin D3, and waistline provides a helpful diagnostic indicator for diagnosing prediabetes in the Chinese Han population.