Goals of Hypertension Treatment
Treatment should ideally be offered to all persons in whom blood pressure reduction, irrespective of initial blood pressure levels, will reduce overall cardiovascular risk (see above). Blood pressure targets for hypertensive patients at the greatest risk for cardiovascular events, particularly diabetic patients, should be lower (< 130/80 mm Hg) than for individuals at lower total cardiovascular risk (< 140/90 mm Hg). As discussed below, hypertensive patients with chronic kidney disease should also be treated until blood pressure is < 130/80 mm Hg. However, since there does not seem to be a blood pressure level below which risk plateaus, these recommendations should be taken as reasonable goals pending further information on optimal targets, which may be even lower. There is no clear consensus on blood pressure goals in the treatment of prehypertension.
Large-scale trials in hypertension have focused on discrete end points occurring over relatively short intervals, thereby placing the emphasis on the prevention of catastrophic events in advanced disease. More recently, in parallel with a new emphasis on hypertension in the context of overall cardiovascular risk, attention is turning to the importance of the long view. Accordingly, treatment of persons with hypertension should focus on comprehensive risk reduction. More careful consideration should be given to the possible long-term adverse consequences of the metabolic derangements linked to some antihypertensives (particularly conventional β-blockers and thiazide diuretics).
Statins should be more widely used. In this respect, there is now evidence from the Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT) that statins can significantly improve outcomes in persons with hypertension (with modest background cardiovascular risk) whose total cholesterol is < 250 mg/dL. The BHS guidelines recommend that statins be offered as secondary prevention to patients whose total cholesterol exceeds 135 mg/dL if they have documented coronary artery disease or a history of ischemic stroke. In addition, statins should be considered as primary prevention in patients with long-standing type 2 diabetes mellitus or in those with type 2 diabetes mellitus who are older than age 50 years, and perhaps in all persons with type 2 diabetes mellitus. Ideally, total and low-density lipoprotein (LDL) cholesterol should be reduced by 30% and 40% respectively, or to approximately
< 155 mg/dL and < 77 mg/dL, whichever is the greatest reduction. However, total and LDL cholesterol levels of < 194 mg/dL and < 116 mg/dL respectively, or reductions of 25% and 30% are regarded as clinically acceptable objectives. Primary prevention with statins might also be reasonably extended to all patients with total cholesterol > 135 mg/dL and a total cardiovascular risk > 20% (to similar target cholesterol levels), but trial evidence for this is not currently available.
Low-dose aspirin (81 mg/day) is likely to be beneficial in patients older than age 50 with either target organ damage or elevated total cardiovascular risk (> 20-30%). Care should be taken to ensure that blood pressure is controlled to the recommended levels in patients receiving aspirin to minimize the risk of bleeding.
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