2010 Volume 49 Issue 13 Pages 1271-1276
Objective High-normal, the intermediate category between normal fasting glucose (NFG) and impaired fasting glucose (IFG), was introduced in the criteria of the disordered glucose metabolism in 2008. The aim of this study was to investigate the risk for future incidence of type 2 diabetes of the subjects with high-normal and to examine how other metabolic variables could be useful for their risk stratification.
Methods A historical cohort study was conducted from 2001 to 2008, inclusive, in 4,165 non-diabetic employees at public schools (2,229 men and 1,936 women; age 45.8±5.9 years, range 25-55 years). They were classified at baseline as NFG with fasting plasma glucose (FPG)<100 mg/dL, high-normal with FPG 100-109 mg/dL, and IFG with FPG 110-125 mg/dL. The incidence of type 2 diabetes (defined either by FPG≥126 mg/dL or by receiving treatments) was measured.
Results The cumulative incidence during a mean follow-up of 5.1 years were 16/3,364 (0.5%), 40/613 (6.5%), and 53/188 (28.2%) in subjects with NFG, high-normal, and IFG, respectively. Multivariate-adjusted odds ratios for the incidence were still significant both in high-normal and IFG compared to NFG. Body mass index (BMI) and alanine aminotransaminase (ALT) were associated with the incidence of type 2 diabetes independently of FPG categories (p<0.05).
Conclusion The future incidence of type 2 diabetes in subjects with high-normal was significantly higher than in those with NFG in this population. BMI and ALT can improve risk stratification in high-normal subjects.
