Glucose and non-glucose predictors of future onset of type 2 diabetes in newly diagnosed essential hypertensives.

BACKGROUND Baseline fasting plasma glucose (FPG) level predicts the onset of type 2 diabetes mellitus (DM). Other predictors have been less investigated. This study aimed to investigate non-glucose predictors together with FPG for future onset of type 2 DM in fresh essential hypertensives. METHODS Consecutive nondiabetic patients with newly diagnosed essential hypertension were prospectively evaluated for diurnal blood pressure (BP) change by ambulatory BP monitoring, vascular endothelial function by plethysmography, and biomarkers by blood biochemistry. They were then given guideline-based treatment and followed-up regularly for more than 5 years. RESULTS During a mean follow-up period of 5.9 years, 6 of the 106 study patients developed DM. Baseline FPG, alanine aminotransferase (ALT) level, and day-night difference in diastolic BP were related to future onset of DM. FPG > 5.8 mmol/L (p = 0.034) and ALT > 31 U/L (p = 0.048) independently and day-night difference in diastolic BP < or = 2.9% potentially predicted new-onset DM (p = 0.089). Simultaneously having at least 2 of the indicators mentioned above at baseline is predictive of new-onset DM. Parameters of reactive hyperemia by plethysmography were not relevant. CONCLUSION In addition to FPG, baseline serum ALT level independently and diurnal diastolic BP changes potentially predicted future onset of type 2 DM in newly diagnosed hypertensives. Both glucose and non-glucose indicators could be examined together for early risk stratification of future DM.