High blood pressure and its association with incident diabetes over 10 years in the Korean Genome and Epidemiology Study (KoGES)

Abstract

OBJECTIVE: No prospective, community-based cohort studies have investigated the association between blood pressure and diabetes in Asian ethnicity. We investigated this issue in a 10-year prospective, community-based study of Koreans. RESEARCH DESIGN AND METHODS: We studied whether high blood pressure was associated with the development of diabetes in a population-based cohort, where we sampled ∼5,000 random subjects each from rural and urban areas (age range 40-69 years) during 2001-2010. Among 10,038 subjects, 8,359 without diabetes at baseline were categorized into normal (n = 4,809), prehypertension (n = 2,141), stage 1 hypertension (n = 804), and stage 2 hypertension (n = 605) groups, according to their blood pressure readings of <120/80 mmHg, 120-139/80-89 mmHg, 140-159/90-99 mmHg, and ≥160/100 mmHg, respectively. The development of diabetes was defined as a fasting glucose concentration of ≥126 mg/dL or a postload glucose concentration of ≥200 mg/dL, based on a 75-g oral glucose tolerance test, or the use of antidiabetic medication. RESULTS: During the 10-year follow-up period, diabetes developed in 1,195 subjects (14.3%). The incidence of diabetes increased from 11.1% in the normal group to 17.0% in the prehypertension group, 17.7% in the stage 1 hypertension group, and 25.8% in the stage 2 hypertension group (P < 0.001). After adjusting for anthropometric factors; family history of diabetes; biochemical parameters including C-reactive protein, A1C, and fasting glucose and postload 2-h glucose levels; and the use of lipid-lowering medications, the hazard risks of diabetes development were 1.23 (95% CI 1.06-1.42), 1.26 (1.04-1.54), and 1.60 (1.30-1.96), respectively, in the prehypertension, stage 1 hypertension, and stage 2 hypertension groups. CONCLUSIONS: Our findings indicate a grade association of baseline blood pressure with the development of diabetes in Korean individuals.