Impaired Fasting Glucose and Impaired Glucose Tolerance Do Not Predict Hypertension: A Community Cohort Study

BACKGROUND Insulin resistance has an important role in the pathogenesis of hypertension. We hypothesized that impaired fasting glucose (IFG) or impaired glucose tolerance (IGT) which represents insulin resistance would predict the development of hypertension. METHODS A total of 4,039 subjects without hypertension or diabetes (1,847 men and 2,192 women; age 49.9 +/- 8.2 years), from the Ansan-Ansung cohorts within the Korean Genome Epidemiology Study, were enrolled in 2001-2002 and restudied in 2005-2006. The association between the incidence of hypertension and IFG, IGT, or other metabolic factors was studied. RESULTS During the 4-year follow-up period, 582 of the 4,039 subjects developed hypertension. At baseline, the prevalence of abdominal obesity, dyslipidemia, and IGT was higher in subjects who became hypertensive compared to those that remained normotensive. The prevalence of IFG was not significantly different between the 2 groups. In a multivariate analysis, abdominal obesity and high serum triglyceride were significant risk factors for the development of hypertension. Neither IFG nor IGT were significantly associated with new-onset hypertension. Although the risk of hypertension was higher with the number of metabolic components present at baseline, IFG and IGT were not significant components compared to other metabolic components, especially when abdominal obesity was taken into account. CONCLUSIONS While metabolic syndrome components related to insulin resistance present at baseline are important risk factors of hypertension, we conclude that coexisting metabolic component, mainly abdominal obesity, rather than IFG and IGT have more predictive value for determining the development of hypertension in a Korean population.