Should We Treat Prehypertension in Diabetes?

E levated blood pressure (BP), even within the normal range, is associated with cardiovascular (CV) morbidity and mortality. Therefore, the Joint National Committee (JNC) VII introduced the term “prehypertension” in the general population, which is defined as BP levels of 120–139 mmHg and 80–89 mmHg for systolic and diastolic BP, respectively (1). Prehypertension includes two different categories of BP: normal (systolic of 120–129 mmHg or diastolic BP of 80–84 mmHg) and high-normal (systolic of 130–139 mmHg or diastolic BP of 85– 89 mmHg). The risk of CV events is increased by twoto fourfold with the coexistence of hypertension and type 2 diabetes. Lowering BP is particularly effective in patients with type 2 diabetes. Therefore, guidelines recommend lowering BP to below 130/80 mmHg in diabetic patients. Thus, the term “prehypertension” is inadequate for patients with type 2 diabetes. It is clear from guidelines that in diabetic patients, the high-normal BP category of prehypertension should be pharmacologically treated. However, there is no evidence that drug treatment is beneficial in the normal BP category of prehypertension. Therefore, despite the devastating effect of elevated BP in type 2 diabetes, drug treatment is not always recommended for all diabetic patients with prehypertension. Hypertension is perhaps best defined by the BP level that has a negative impact on the CV system. Thus, numerical definitions, although hotly debated by numerous guideline committees, are not helpful to practicing physicians. Recent guidelines set the target level of BP for uncomplicated hypertension to below 140/90 mmHg and in the diabetic hypertensive patient to below 130/80 mmHg (1,2). Solid evidence exists showing that the benefits of BP lowering are far more pronounced in the diabetic than in the nondiabetic hypertensive patient. In light of the benefits of BP lowering in diabetic patients, there is a dilemma as to whether diabetic patients with prehypertension should be medically treated to lower BP. I will endeavor to analyze the available data to determine what therapeutic approach should be adopted for diabetic patients with prehypertension.