Low fasting plasma glucose level as a predictor of new-onset diabetes mellitus on a large cohort from a Japanese general population

Although fasting plasma glucose levels <70 mg/dL are associated with a high incidence of cardiovascular disease (CVD), whether there is any risk of new-onset diabetes mellitus owing to fasting plasma glucose at this range has not been clarified. We measured the odds ratio (OR) of new-onset diabetes mellitus relative to fasting plasma glucose levels at various ranges in a nation-wide Japanese population with and without CVD history. Of 186,749 participants without diabetes in 2008, 171,408 had no history of CVD, while 15,341 did. Participants were classified into 8 categories according to their fasting plasma glucose levels. Unadjusted and multivariable-adjusted logistic regression models were used to measure the OR of new-onset diabetes mellitus in the 3-year follow up. In all participants, multivariable-adjusted OR increased when fasting plasma glucose levels were <70 mg/dL or 90–125 mg/dL. Participants without CVD showed increased OR when glucose levels were <70 mg/dL or 90–125 mg/dL. Participants with a history of CVD showed increased OR with glucose levels of 95–125 mg/dL. The risk of new-onset diabetes mellitus is higher when fasting glucose levels are <70 mg/dL, indicating that the paradox of fasting glucose seeks a new risk stratification for new-onset diabetes mellitus.