The likelihood of diabetes based on the proposed definitions for impaired fasting glucose.

The current study aimed to evaluate whether individuals with fasting plasma glucose (FPG) of 5.6-6.0 mmol/l has a similar risk profiles for diabetes or impaired glucose tolerance (IGT) to those with FPG of 6.1-6.9 mmol/l. A community-based cross-sectional survey in Chinese adults (20-74 years) was conducted during April-July in 2002. Participants without a prior history of diabetes underwent a standardized 2-h 75 g oral glucose tolerance test. Positive likelihood ratios were calculated to estimate the odds of having diabetes or IGT for subjects with different FPG levels. Among 1856 participants, prevalence of IFG increased from 12.4 to 28.2% with the cut-off value of FPG lowered from 6.1 to 5.6 mmol/l. Individuals with FPG of 6.1-6.9 mmol/l were more obese and insulin resistant than those with FPG of 5.6-6.0 mmol/l. The positive likelihood ratio for diabetes and IGT were 1.83 (1.28-2.61) and 2.60 (1.96-3.44) in subjects with FPG of 6.1-6.9 mmol/l, and 0.54 (0.30-0.95) and 1.47 (1.11-1.95) for those with FPG of 5.6-6.0 mmol/l, respectively. In conclusion, the likelihood of diabetes and IGT was lower in subjects with FPG of 5.6-6.0 mmol/l than in those with FPG of 6.1-6.9 mmol/l. The clinical and social implication of labelling more individuals with impaired fasting glucose needs to be further studied.