Treatment of Hypertension in the Very Elderly: a Clinician's Point of View

The literature continues to remind physicians of a well‐known fact: The number of elderly persons is increasing rapidly. Within the next 20 years the number of Americans over age 65 years will be more than 50 million. It is also estimated that more than 60% of individuals in this age group will have hypertension. Thus, the problem of controlling hypertension in the elderly assumes greater and greater importance. Yet, a large majority of elderly people are not treated at all or are not treated to the goal blood pressure of <140/90 mm Hg that has been set by national guideline committees. A significant improvement in the management of this group of people is clearly necessary.

DATA ON BENEFITS IN THE ELDERLY AND VERY ELDERLY

Study after study has reported that treating hypertension in the elderly will reduce stroke, heart failure, and all cardiovascular events. Data from the Systolic Hypertension in the Elderly (SHEP) trial, ¹ the Systolic Hypertension in the Elderly in Europe (Syst‐Eur) trial, ² the Medical Research Council (MRC) trial, ³ and the European Working Party on Hypertension in the Elderly (EWPHE) trial, ⁴ have noted a more than 30% reduction in stroke and a reduction of 15%–40% in all cardiovascular events in treated compared with control elderly patients, even in subjects older than age 75 years. A greater than 50% reduction in the occurrence of heart failure has also been noted. The prevention of heart failure, which occurs in approximately 10% of all patients over the age of 75 years and is a major reason for hospitalization in this age group, should be an important objective of treatment.

In the Syst‐Eur study ² there was also a signifi cant reduction in the occurrence of vascular dementia in treated compared with control individuals; other studies, like the Study on Cognition and Prognosis in the Elderly (SCOPE) trial, ⁵ have suggested a similar outcome. Obviously, this finding is also of great importance. It is estimated that the number of patients with dementia will more than double within the next 15–20 years, primarily in those patients aged 75 years or older. Treating hypertension may help prevent these events.

MANAGEMENT MAY NOT BE SIMPLE

Management of elderly patients may be complicated; the occurrence of diabetes, hyperlipidemia, and various tachycardias are more common in this population group than in younger patients. Despite the results of controlled studies like the Hypertension Detection and Follow‐up Program (HDFP) trial, ⁶ which reported that the elderly tolerate medication well and that side effects are no greater in these patients than in the young, this may not be true in many patients. It is not always possible to achieve goal blood pressures in elderly patients because of side effects that may result from physiologic changes in this age group.

RECENT CLINICAL TRIAL RESULTS

Recent clinical trials in elderly patients have demonstrated that blood pressure can be lowered in patients either with diuretic/β‐blocker therapy or the use of an angiotensin‐converting enzyme inhibitor or calcium channel blocker‐based therapy. But, for example, in the Swedish Trial in Older Persons (STOP‐2), ⁷ it proved difficult to reduce systolic blood pressure to below the goal of 140 mm Hg in many patients. Some recent trials have provided guidance regarding the effects of specific medications in patients over the age of 75 years. A recently reported trial, the Antihypertensive and Lipid‐Lowering treatment to prevent Heart Attack Trial (ALLHAT), ⁸ studied more than 33,000 patients with a mean age of 67 years. This trial was not placebo controlled; it was a comparative study of three different classes of drugs in elderly subjects at high risk. Results are of interest. The ALLHAT trial evaluated more than 5700 patients over the age of 75 years and more than 13,000 patients over the age of 65 years. Over a 5‐year period mean blood pressures were reduced from 147/81 mm Hg to 135/77 mm Hg. There were minimal clinically significant differences in the achieved blood pressures in the over 65 years group among the calcium channel blocker and diuretic groups. Because of the large numbers of patients, the changes of <1 mm systolic or diastolic pressures between the amlodipine and the diuretic group (chlorthalidone) were, however, considered statistically significant. The chlorthalidone group achieved a systolic blood pressure that was 3 mm less than the group on lisinopril. This was statistically significant. About two thirds of the elderly patients achieved a goal blood pressure of below 140/90 mm Hg.

ALLHAT RESULTS IN THE 75 YEARS AND OLDER GROUP

Morbidity/mortality data were looked at in the 75 years and over group, comparing chlorthalidone with amlodipine. There were no statistically significant differences between the two agents in fatal and nonfatal myocardial infarctions, all‐cause mortality, coronary heart disease, and strokes, but there was a statistically significant difference in the occurrence of heart failure. A chlorthalidone based regimen reduced heart failure occurrence by 22% compared with an amlodipine‐based treatment program. There were also no differences in any of the primary end points when chlorthalidone was compared with an angiotensin‐converting enzyme inhibitor (lisinopril) in patients over age 75 years. There were, however, marginally statistically significant differences in the occurrence of heart failure and combined cardiovascular events favoring chlorthalidone.

Thus, ALLHAT demonstrates that presently available antihypertensive medications lower blood pressure in the elderly and very elderly and that coronary heart disease event rates are similar among a diuretic, CCb, and ACE inhibitor except for the occurrence of heart failure where results were better with a diuretic.

HOW SHOULD CLINICIANS TRANSLATE TRIAL DATA INTO PRACTICE?

As clinicians we should pay careful attention to the results of clinical trials. Treatment of the elderly, even patients over age 80 years with systolic or systolic/diastolic hypertension, is beneficial—cardiovascular events, especially strokes and heart failure, are reduced by treatment. ⁹ It is no longer appropriate to say that a 75‐or 80‐year old person with elevated blood pressure who feels well should be left alone. He/she should be treated with medications, if necessary, and certainly with sodium restriction because the elderly are more salt sensitive than the young. The currently available medications are effective and generally well tolerated. However, the very carefully controlled clinical trials include patients who are highly motivated and they have agreed to a protocol and to staying in a study for 3–5 years. Health care personnel in the trials are trained to keep people on therapy and to follow a careful protocol. These situations may not reflect the real world of practice. Many clinicians find some differences between the results of clinical trials and what they encounter in practice.

It is obvious to many clinicians that it is more difficult to treat a 75‐year‐old man or woman with a blood pressure of 170/80 mm Hg than a 40‐year old with a blood pressure of 200–210/110 mm Hg. In the latter case the use of two or three medications, one of which should be a diuretic, will generally control blood pressure. In the former case, lowering the blood pressure from 180, for example, to 160 may result in fatigue or dizziness or just “not feeling well.” It is tempting on the part of a physician to stop treatment and consider the patient who was originally relatively asymptomatic a treatment failure. But that is not the correct approach in a majority of cases.

Because cardiac output and renal function are reduced in the elderly, it is not infrequent for some symptoms to occur as blood pressure is lowered. Because baroreceptors are not as sensitive in the elderly and may have been “reset” in hypertensive people, it is not unusual for them to have some trouble adjusting to lower pressures—postural hypotension and dizziness are not unusual, especially postprandial. Hence, there should be a two‐step or two‐stage approach to therapy. Clinical judgment should play a major role in management.

Although guidelines for reducing pressure in the elderly are important, it is also important to adjust a treatment program and change objectives if a patient feels bad. It is also important to recognize that even a small reduction in systolic blood pressure in the elderly will reduce strokes and congestive heart failure as well as overall cardiovascular events.

APPROACHES TO IMPROVE OUTCOMES IN VERY ELDERLY PATIENTS

Physicians must become convinced that the data on outcome are valid. Lowering blood pressure to as close to goal levels of below 140 mm Hg systolic will reduce strokes, heart failure, and overall cardiovascular events even in the elderly over age 80 years. Even if no benefit accrued other than reducing strokes and heart failure, this would be a major reason to treat these patients.

Secondly, when we try to achieve a goal of below 140 mm Hg systolic or as close to this as possible, a major consideration should be to do this with as few annoying side effects as possible. Therapy should probably begin with a diuretic in small doses, that is, 12.5 mg hydrochlorothiazide or its equivalent. If this is ineffective, the addition of a small dose of a calcium channel blocker, β blocker, angiotensin‐converting enzyme inhibitor, or an angiotensin receptor blocker is indicated. In some instances the use of a medication other than a diuretic as initial therapy may be appropriate. Probably only about 40% of patients in the age group will achieve a systolic blood pressure of below 140 mm Hg with any of these agents as monotherapy the therapist must be prepared to carefully up‐titrate medications or, if necessary, add medications from different classes. A majority of patients with isolated systolic hypertension (blood pressure >140/<90 mm Hg) will require multiple drugs to achieve goal blood pressures. One consideration of treatment with a diuretic in the elderly is the necessity to avoid hypokalemia if possible. In the SHEP study, ¹ benefits were minimized in patients who experienced potassium levels below 3.5 mg/dL with blood pressure lowering.

If an elderly patient remains asymptomatic, medication should be up‐titrated as in a younger person, to achieve goal blood pressures. If symptoms occur as pressures are reduced, it is prudent to continue the same dose of the medication or cut back slightly and wait for several weeks or longer before attempting to increase dosage again to achieve a result. A two‐step, slow process of increasing therapy is more effective in these patients. ¹⁰

Some investigators disagree with the above approach and advocate that therapy should be advanced fairly rapidly because data suggest a reduction in stroke events within a short time after treatment. I do not believe that overall results with this approach will improve outcome; too many patients will discontinue therapy because of adverse reactions.