Dysglycaemia in non-diabetic hypertensive patients: comparison of the impact of two different classifications of impaired fasting glucose on the cardiovascular risk profile.

The clinical correlates and risk profile of prediabetes (fasting plasma glucose (FPG) values in the upper normal limits but below the diabetic threshold) in hypertension, an insulin-resistant, prodiabetogenic condition, are scarcely known. For this reason, we evaluated 982 non-diabetic (FPG,<126 mg 100 ml(-1) and no antidiabetic treatment) referred hypertensive patients without a history of cardiovascular disease grouped by mild (100-109 mg 100 ml(-1)) and advanced (110-125 mg 100 ml(-1)) dysglycaemia compared with normal FPG (<100 mg 100 ml(-1)). FPG, total and high density lipoprotein (HDL) cholesterol, triglycerides and total white blood cell count were assessed by standard methodologies; 10-year predicted coronary heart disease (CHD) risk was approximated by the Framingham risk score (FRS). Metabolic syndrome (MetS) was diagnosed by standard categorical criteria using either 110 or 100 mg 100 ml(-1) as a threshold for impaired fasting glucose (IFG). FPG was above 110 in 13% and between 100 and 109 in 20% of patients. In both dysglycaemic groups, perturbed glucose homeostasis was associated with abnormally high fasting triglycerides, low HDL cholesterol, obesity, worse CHD risk profile and higher white blood cell count. MetS was highly prevalent and its distribution pattern was markedly influenced by the definitions of IFG based on different FPG cutoffs. Thus, even mildly perturbed glucose homeostasis associates with atherogenic dyslipidaemia, obesity and adverse risk profile in non-diabetic hypertensive patients. Because of its prediabetic nature, dysglycaemia should prompt measures to prevent new-onset diabetes, although the role of IFG as an independent risk factor awaits specifically designed intervention trials.