Hemoglobin A1c Is Positively Correlated with Framingham Risk Score in Older, Apparently Healthy Nondiabetic Korean Adults

BACKGROUND: Several studies have suggested that elevated levels of hemoglobin A1c (HbA1c) are associated with cardiovascular disease (CVD) in nondiabetic individuals. However, it is unclear whether HbA1c levels can serve as a simple screening marker for increased CVD risk in nondiabetic individuals. Our objective was to evaluate the relationship between HbA1c levels and CVD risk using the Framingham risk score (FRS) in older, apparently healthy nondiabetic Korean adults. METHODS: We retrospectively studied 2,879 Korean adults between the ages of 40 and 79 who underwent voluntary health check-ups at the Health Promotion Center of our hospital from July 2009 to June 2011. Subjects were subdivided based on their HbA1c levels into four groups: tertiles within the HbA1c normal tolerance range and a group for subjects with an increased risk for diabetes (IRD). RESULTS: The mean FRS for the upper tertile (9.6±3.8) group was significantly higher than that of the middle tertile (8.4±4.0) and lower tertile (7.6±3.8) groups. In addition, FRS was highest in the IRD group (10.5±3.7). Multiple linear regression analysis demonstrated that HbA1c levels exhibited a significant positive correlation with FRS when adjusted for confounding variables in all subjects (β±standard error [SE], 0.018±0.002; R(2), 0.131), women (β±SE, 0.023±0.003; R(2), 0.170), and men (β±SE, 0.016±0.004; R(2), 0.109). CONCLUSION: HbA1c levels were positively correlated with FRS in older, apparently healthy nondiabetic Korean adults. We propose that HbA1c levels may reflect CVD risk in nondiabetic individuals.