Treating Hypertension in the Elderly

More than 75% of patients older than 75 years have hypertension. In older individuals, hypertension is the most important risk factor for cardiovascular disease, and cardiovascular disease remains the most important cause of morbidity and mortality in the elderly.

New data, particularly the HYVET trial (N. Engl. J. Med. 2008;358:1887-98), have led to a reassessment of recommendations for treatment of hypertension in the elderly, culminating in a joint statement on hypertension in the elderly issued and endorsed by several organizations, including the American Heart Association, the American College of Physicians, and the American College of Cardiology.

Benefits of Antihypertensive Treatment

Poorly controlled hypertension is a strong predictor of cardiovascular risk in adults. The incidence of stroke, myocardial infarction, peripheral vascular disease, and chronic kidney disease (CKD) all increase in patients with hypertension, and are more common with increasing age. Lowering of BP by the use of pharmacologic and nonpharmacologic means reduces this risk.

This has led to strong consensus that blood pressure greater than 140/90 mm Hg should be treated and that in select populations – including patients with diabetes mellitus, CKD, left ventricular dysfunction, peripheral artery disease, and coronary artery disease – the target should be even lower. These potential benefits are evident in the elderly and very elderly, just as they are in younger populations. The elderly have a greater absolute risk of end-organ damage, including clinical cardiovascular disease, than do younger people.

Disadvantages of Antihypertensive Treatment

There are potential drawbacks to pharmacologic treatment of hypertension in the elderly. Many antihypertensive medications produce significant morbidity – even mortality – because of side effects, including postural hypotension, bradycardia, and other arrhythmias, and metabolic disturbances – all of which are more common in the elderly. There is also a significant risk of side effects being magnified because of drug-drug interactions, with the average elderly patient taking more than six prescription medications.

Many – but not all – trials of antihypertensive treatment in the very elderly have demonstrated a decrease in cardiovascular mortality, but no impact on overall mortality, suggesting there might be a counterbalancing adverse effect of drug treatment.

Diagnosis

The diagnosis of hypertension should be based on at least three blood pressure measurements greater than 140/90 mm Hg, taken on two or more separate office visits. The guidelines emphasize the role of home or ambulatory blood pressure monitoring. White-coat hypertension is more common in the elderly, and the risks of overtreatment are greater than in the young. Out-of-office BP monitoring is recommended for patients with in-office hypertension but without end-organ damage.

Management/Treatment

P Drug treatment is recommended to achieve BP less than 140/90, but with "a greater degree of caution" than in younger patients. Particular attention should be paid to "quality of life" issues, including cognitive, physical, and sexual function, which all may be more prone to adverse medication effects in the elderly.

P Medications should be initiated at the lowest dose and be increased gradually to maximum tolerated dose.

P If inadequate BP response is achieved with a single drug, a second medication should be added. If there is inadequate BP response on full dose of two classes of drugs, then a third drug from another class should be added.

P If a diuretic is not the initial drug, it is usually indicated as the second drug.

P If initial BP is more than 20/10 above target, therapy with two antihypertensive drugs may be considered at the outset. Most elderly patients with hypertension will eventually require at least two drugs for adequate control.

P For those older than 80 years, a systolic BP of 140-145 mm Hg is acceptable, and blood pressure below 130/65 should be avoided.

Specific Medications

Thiazides are recommended for initiating treatment in most cases. They are generally well tolerated in the elderly and improve cardiovascular, cerebrovascular, and renal adverse end points. On the other hand, they can deplete electrolytes and intravascular volume. Patients should be monitored carefully for side effects, particularly at higher doses.

Beta-blockers appear to be less effective in the elderly. They are indicated in elderly hypertensive patients with coexisting coronary artery disease, heart failure, and conditions such as migraine or essential tremor.

Calcium antagonists may be appropriate in elderly patients, particularly those with comorbid angina or some arrhythmias. Constipation, ankle edema, and postural hypotension may be problematic.

ACE inhibitors and ARBs often are well tolerated and effective in elderly patients, and are considered first-line in patients with diabetes and CKD.

Alpha-blockers and nonspecific vasodilators should be used with caution in elderly patients. The ALLHAT trial showed significantly increased cardiovascular events in patients taking an alpha-blocker, compared with a diuretic.