Background: Previous studies have shown that Type 2 diabetes mellitus (T2DM) is usually preceded by a condition known as pre-diabetes. However, few studies evaluate the rate of each status of impaired glucose regulation progressed to T2DM and its related metabolic disorders impacting the development.
Aim: To investigate the natural outcome of glucose metabolism among Shanghai adult residents during a 5-yr period, and estimate the metabolic characteristics related with the conversion of glucose tolerance.
Subjects and methods: A cross-sectional survey with multiple- stage and random sampling was conducted among 1869 adult residents from Shanghai Pudong New District in 2002. In 2007, 1042 non-diabetic subjects were successfully followed up. All the participants completed a questionnaire and underwent anthropometric measurements and a 75-g oral glucose tolerance test.
Results: The incidence of diabetes was higher in isolated impaired glucose tolerance (i- IGT), isolated impaired fasting glucose (i-IFG), and combined fasting and post-prandial hyperglycemia (IFG/IGT) group when compared to that in normal glucose tolerance group, as relative ratios with 95% confidence intervals of 9.2 (5.5- 15.2), 7.5 (3.6-15.7), and 13.2 (5.8-30.2), respectively. Subjects who had 2 or more metabolic disorders had a 2-3-fold higher incidence than those with less than 1 metabolic disorder (all p<0.001).
Conclusions: People with pre-diabetes are at increased risk of diabetes, suggesting the need for frequent screening in theloe people with several metabolic disorders.