Prehypertension--prevalence, health risks, and management strategies.

Prehypertension (blood pressure 120-139/80-89 mmHg) affects ~25-50% of adults worldwide, and increases the risk of incident hypertension. The relative risk of incident hypertension declines by ~20% with intensive lifestyle intervention, and by 34-66% with single antihypertensive medications. To prevent one case of incident hypertension in adults with prehypertension and a 50% 5-year risk of hypertension, 10 individuals would need to receive intensive lifestyle intervention, and four to six patients would need to be treated with antihypertensive medication. The relative risk of incident cardiovascular disease (CVD) is greater with 'stage 2' (130-139/85-89 mmHg) than 'stage 1' (120-129/80-84 mmHg) prehypertension; only stage 2 prehypertension increases cardiovascular mortality. Among individuals with prehypertension, the 10-year absolute CVD risk for middle-aged adults without diabetes mellitus or CVD is ~10%, and ~40% for middle-aged and older individuals with either or both comorbidities. Antihypertensive medications reduce the relative risk of CVD and death by ~15% in secondary-prevention studies of prehypertension. Data on primary prevention of CVD with pharmacotherapy in prehypertension are lacking. Risk-stratified, patient-centred, comparative-effectiveness research is needed in prehypertension to inform an acceptable, safe, and effective balance of lifestyle and medication interventions to prevent incident hypertension and CVD.