Long-Term Risk of Hypertension in Normoglycemia and Prediabetes, and Their Relation to the Change of Glycemic State.
BACKGROUND
Although increasing evidence has suggested the significant association between dysglycemia and hypertension, this association is less well described in prediabetes. Additionally, it is unclear how risk of hypertension varies according to the change of glycemic state.


METHODS
Five thousand four hundred thirteen nondiabetic Koreans were dichotomized into normoglycemia (NG) and prediabetes group and followed-up for 10 years. Cox proportional hazard model was used to evaluate hazard ratios (HRs) with 95% confidence interval (CI) [adjusted HRs (95% CI)] for the development of hypertension. Subgroup analysis was conducted in subdivided glycated hemoglobin (HbA1c) with <5.7%, 5.7-5.9%, and 6.0-6.4% and 2 hour post-load glucose (2 hr-PG) with <140, 140-169, and 170-199 mg/dl. The glycemic states are NG, prediabetes, and diabetes mellitus (DM), which are used in evaluating the change of glycemic state during follow-up in baseline NG (NG → NG, NG → prediabetes, and NG → DM) and baseline prediabetes (prediabetes → prediabetes and prediabetes → DM).


RESULTS
Compared with NG, prediabetes was not significantly associated with the risk of hypertension [1.11 (0.997-1.23)]. HbA1c ≥5.7% [1.13 (1.02-1.26)] and 2 hr-PG ≥140 mg/dl [1.15 (1.004-1.31)] were marginally associated with the risk of hypertension. In subgroup analysis, only 2 hr-PG of 170-199 mg/dl showed the significantly increased risk of hypertension [1.37 (1.09-1.73)]. Compared with the maintaining glycemic state, the progression of glycemic state had the significantly increased risk of hypertension [NG → prediabetes; 1.41 (1.19-1.67), NG→DM; 1.77 (1.36-2.30), and prediabetes → DM; 1.32 (1.13-1.55)].


CONCLUSION
The progression of glycemic state was a strong determinant on the development of hypertension.