Blood pressure, particularly systolic pressure, increases with increasing age. The risk associated with hypertension does not decline with age, and the criteria that define hypertension, outlined in the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7; see references at end of chapter and Table 46.1), are not age adjusted. Epidemiologic studies, including the National Health and Nutrition Examination surveys, suggest that the prevalence of hypertension in persons aged 65 years and older is between 50% and 70%; the prevalence is highest among older black Americans. In contrast to younger hypertensive populations, among whom men predominate, in the older hypertensive population the prevalence rate is higher for women, particularly for those above the age of 75 years. Over the past 50 years the use of antihypertensive medications has increased, and the prevalence rates of elevated blood pressure, left ventricular hypertrophy, and cardiovascular and stroke mortality have all declined. However, these trends have been delayed among the older population, and blood pressure remains poorly controlled in many older patients despite treatment for hypertension.
Many of the physiologic changes that occur with aging contribute to the increase in blood pressure, but life-style factors such as obesity and physical inactivity and the presence of comorbid diseases are also important contributors. Several physiologic changes combine to increase peripheral vascular resistance, the physiologic hallmark of hypertension in older persons. Several mechanisms contribute to the age-associated increase in arterial vascular stiffness. Arterial stiffness, or reduced vascular compliance, provides the best explanation for the relatively greater increase in systolic pressure and the increase in pulse pressure (the difference between systolic and diastolic pressure) observed with aging. Decreased sensitivity of the baroreflex, perhaps related to decreased arterial distensibility, contributes to an increase in blood-pressure variability and sympathetic nervous system activity. The dynamic regulation of vascular tone is affected by impairments in vasodilator systems (eg, production of nitric oxide by vascular endothelial cells and vasodilatation mediated by β-adrenergic receptors) and heightened vasoconstriction mediated by α-adrenergic receptors. Alterations in kidney function as well as in neurohumoral systems that are involved in sodium balance combine to increase the proportion of older hypertensive persons whose blood pressure increases with increased sodium intake. Approximately two thirds of older hypertensive persons have sodium-sensitive hypertension.
The regulation of blood-pressure homeostasis may be impaired in older hypertensive persons, making older people with elevated systolic blood pressure more likely to develop both orthostatic and postprandial hypotension. Maintaining normal blood pressure and cerebrovascular and coronary perfusion in the face of hypotensive stimuli related to postural challenge, meals, or medications requires the integrated coordination of multiple compensatory mechanisms. The age-associated decline in baroreflex sensitivity and alterations in sympathetic nervous system function impair the dynamic regulation of blood pressure. Because of the blunted sensitivity of the baroreflex, a greater reduction in blood pressure occurs before the increase in heart rate and other compensatory mechanisms are activated. Other pathophysiologic changes that impair blood-pressure regulation include arterial and cardiac stiffness and a decrease in early diastolic filling.
Accurate measurement of blood pressure is the most critical aspect of the diagnosis of hypertension in the older patient. Because variability in blood pressure increases with age, the diagnosis of hypertension should be made by using the average of several blood-pressure readings taken on each of three visits. Ambulatory blood-pressure monitoring may be necessary for patients with extreme blood-pressure variability or possible “white-coat” hypertension. Clinicians should be aware of an auscultatory gap, which can lead to underestimation of the true systolic blood pressure and can indicate arterial stiffness. Determining the systolic blood pressure by palpation avoids this problem.
Once a diagnosis of hypertension has been made, the remainder of the clinical evaluation centers on excluding secondary forms of hypertension (using an approach similar to that used in younger patient populations), identifying target organ damage, and determining cardiovascular risk factors and the presence of comorbid conditions. Although most older patients have essential hypertension, secondary forms of hypertension should be suspected in the presence of malignant hypertension, a sudden increase in diastolic blood pressure, worsening level of control, or poorly controlled blood pressure on a regimen of three antihypertensive medications. Renovascular disease is the most common secondary form of hypertension among older patients. Treatment decisions should take into account cardiovascular disease, target-organ damage (eg, left ventricular hypertrophy), diabetes mellitus, and other comorbid diseases. Finally, the patient’s smoking history, dietary intake of sodium and fat, alcohol intake, and the level of usual physical activity should be determined to allow the clinician to individualize advice about life-style modifications to help control blood pressure as well as reduce overall cardiovascular disease risk factors.
The overwhelming consensus derived from the results of several randomized placebo-controlled clinical trials is that treatment of hypertension in older persons is safe and effective. Meta-analyses of more than forty randomized clinical trials of antihypertensive therapy have provided compelling evidence that treatment is effective in reducing cardiovascular (eg, chronic heart failure) and cerebrovascular (eg, stroke) morbidity and mortality. A meta-analysis of outcome trials in systolic hypertension among older patients demonstrated that treatment was associated with significant reductions in overall mortality, cardiovascular events, and stroke. The treatment effect was largest in men, in those aged 70 years and over, and in those who had greater pulse pressures. Of note, few participants in randomized controlled trials of hypertension treatment were over 80 years old and almost none were over 85 years. As the treatment effect is delayed about 5 years, consideration needs to be given to initiating or continuing antihypertensive medication in very elderly persons.
As with other chronic conditions in older patients, it is important to balance the recognized beneficial effects of antihypertensive therapy with the potential impact on the patient’s functional status and quality of life (eg, with the development of orthostatic hypotension). A treatment approach using modalities least likely to produce adverse effects and targeting a reduction in systolic blood pressure to 135 to 140 mm Hg and diastolic blood pressure to 85 to 90 mm Hg should be developed. For individuals with type 2 diabetes, a systolic blood pressure goal of less than 130 mm Hg is recommended. For persons with markedly elevated systolic blood pressure, an intermediate target, such as 160 mm Hg, may be an appropriate initial goal in the absence of target-organ damage. The focus of treatment should be on the systolic blood pressure and pulse pressure, since among older hypertensive persons, they are stronger predictors than the diastolic blood pressure of adverse outcomes. The systolic blood pressure alone correctly classifies the blood-pressure stage of more than 99% of older hypertensive patients. In addition, analysis of data from the Systolic Hypertension in the Elderly Program study demonstrates a significant relationship between pulse pressure and the risk for stroke and overall mortality that is independent of the level of mean arterial pressure.
Nonpharmacologic therapy may be effective for older persons with stage 1 hypertension (140 to 159 mm Hg systolic or 90 to 99 mm Hg diastolic blood pressure) and is an important adjunct to drug treatment because of synergistic effects with antihypertensive drugs and the benefits realized through the reduction in other cardiovascular risk factors (see Table 46.2). Life-style modifications that target the typical characteristics of the older hypertensive person—overweight, sedentary, and salt-sensitive—are likely to be effective. The randomized Trial of Nonpharmacologic Interventions in Elderly study, which evaluated the effects of dietary sodium restriction and weight loss in elderly patients, demonstrated that relatively modest reductions in dietary sodium intake (40 mmol per day) and in body weight (4 kg) are accompanied by a 30% decrease in the need to reinitiate pharmacologic treatment. A meta-analysis of randomized trials assessing the effects of dietary sodium restriction demonstrated a significant reduction in systolic (a mean decrease of 3.7 mm Hg for each decrease of 100 mmol per day in sodium intake) but not in diastolic blood pressure. This differential reduction in systolic pressure is particularly well suited for the older hypertensive patient. Persons with stage 1 hypertension who do not have diabetes mellitus should complete a 6-month trial of nonpharmacologic therapy before adding an antihypertensive medication if the target blood pressure is not achieved. (See also Physical Activity; Malnutrition.)
The general approach to pharmacologic management of the older hypertensive patient is presented in the JNC 7. General principles regarding drug selection are reviewed here and summarized in Table 46.3. Drug selection may be affected by whether the patient has simple hypertension or hypertension complicated by any of several comorbid conditions (eg, diabetes mellitus, coronary artery disease or history of myocardial infarction, heart failure, prostatism) that may influence the choice of drug. Racial and ethnic background likely has an effect on an individual’s response to antihypertensive drug therapy; the blood-pressure reduction resulting from monotherapy with angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers is somewhat attenuated among blacks.
Given the available evidence to date, for those with simple, uncomplicated hypertension, the initial antihypertensive drug choice is a low-dose thiazide-type diuretic. A majority of patients will not reach their systolic blood pressure goal on a single drug; JNC 7 recommends considering starting patients on two drugs if the initial blood pressure is more than 20 mm Hg above the target level. In this circumstance, partly in light of the results from the Second Australian National Blood Pressure Study, adding an ACE inhibitor to a low-dose thiazide-type diuretic is a combination that is reasonable to consider. Beyond these general recommendations for initial therapy, there is no universally accepted approach to choosing alternative agents or combination therapies; these decisions should be made on an individual basis that considers the advantages and disadvantages of the drug together with the patient’s comorbidities. Finally, centrally acting agents (eg, clonidine, methyldopa) and those more likely to produce orthostatic hypotension should be avoided in most older patients.
Therapy with low-dose thiazide-type diuretics (eg, hydrochlorothiazide ≤ 25 mg daily, or the equivalent) has demonstrated significant benefits in mortality, stroke, and coronary events in randomized clinical trials in older hypertensive patients. The two thiazide-type diuretics in common usage—the benzothiadiazine hydrochlorothiazide and the benzene sulfonamide chlorthalidone—differ markedly in their chemical structure, potency, and pharmacokinetics. The effectiveness of both drugs has been demonstrated in clinical trials, although many recent trials, such as the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT), have used chlorthalidone. Although the direct comparability of these two diuretics has not been rigorously examined, the available evidence suggests that their blood-pressure lowering and other effects are comparable. These beneficial effects, combined with their relative safety, favorable adverse-effect profile (their adverse metabolic effects—hypokalemia, hyperuricemia, and glucose intolerance—are attenuated at lower doses), once-daily dosing, and low cost have led to the recommendation that diuretics are preferred for initial therapy. Another advantage is that diuretic therapy leads to a disproportionate reduction in systolic relative to diastolic blood pressure, and it is better than other agents at achieving a reduction in systolic blood pressure. Thiazide diuretics are also well suited for use in combination therapies because of synergistic effects with other antihypertensive drug classes. The importance of maintaining a normal potassium level during therapy with thiazide-type diuretics deserves emphasis. Adequate potassium replacement during diuretic-based treatment has been shown to prevent the risk of arrhythmias as well as decrease the impairment in glucose tolerance.
ACE inhibitors have been demonstrated to be effective in lowering blood pressure in older hypertensive patients. Given the results from the Second Australian National Blood Pressure randomized controlled trial, there is support for using ACE inhibitors as initial monotherapy for simple hypertension in older hypertensive patients, especially in men. Drugs in this class are generally well tolerated (with the exception of cough during ACE inhibitor therapy), and they do not adversely affect the central nervous system or metabolic profile. There are compelling benefits from using ACE inhibitors in those patients with coexisting diabetes mellitus (particularly when there is microalbuminuria), as well as in those with left ventricular systolic dysfunction.
There have been no randomized controlled trials that have compared outcomes from treatment with angiotensin receptor blockers (ARBs) with diuretics among older hypertensive patients. The recently completed ALLHAT study did not include an ARB arm. Results from a network meta-analysis suggest that diuretic therapy is superior to ARBs for most outcomes. In the absence of data from randomized controlled trials to support their benefit with respect to cardiovascular events and mortality, therapy with an ARB generally should not be considered as initial monotherapy for simple hypertension. ARB therapy may be considered in patients with underlying diabetes, heart failure, or chronic kidney disease, especially if they are not able to tolerate ACE inhibitor therapy.
Therapy with calcium channel antagonists (CCAs), in particular, long-acting agents in the dihydropyridine (nifedipine-like) class, has been shown in the Systolic Hypertension in Europe and China trials to lead to significant reduction in stroke risk in older hypertensive patients. The pathophysiologic (reduction in peripheral vascular resistance) and adverse-effect (absence of central or metabolic effects) profiles of the CCA class are other factors that support their use in this patient population. Although these agents are not recommended as first-step therapy, they may be considered as second-line drugs, generally in combination with a thiazide-type diuretic. Because of age-related changes in their pharmacokinetics, lower doses of CCAs should be used. Short-acting CCAs should not be used to treat hypertension.
β-Receptor antagonists are recommended in the JNC 7 report as another option for second-line drug therapy. β-Receptor antagonists should not be considered as first-line monotherapy for simple hypertension in older patients. Analysis of evidence from randomized controlled trials has questioned the efficacy of β-blockers in older hypertensive persons. Results from these studies suggest that therapy with a β-receptor antagonist is less effective than therapy with low-dose thiazide diuretics with respect to blood-pressure reduction and in the prevention of cardiovascular events, stroke, and death. In addition, β-blockers are more likely to be discontinued because of adverse effects. Because of their effectiveness in the management of symptomatic coronary artery disease, in secondary prevention following myocardial infarction, and in certain heart failure settings, β-receptor antagonists should be considered for older patients whose hypertension is complicated by these comorbid conditions.
Although the reduction in peripheral vascular resistance that occurs with therapy using an α-receptor antagonist is particularly appropriate for the pathophysiologic profile of geriatric hypertension, and although these agents are effective in blood-pressure reduction, the development of postural hypotension has limited the widespread use of this class of antihypertensive for treating elderly patients. The treatment arm that included persons randomized to therapy with the α-receptor antagonist doxazosin in the ALLHAT study was stopped early because of a higher rate of cardiovascular end points, including a twofold greater likelihood of being hospitalized for heart failure. α-Receptor antagonist therapy, usually in combination with another drug, might be considered for treating older hypertensive men with prostatism since these drugs have been shown to be efficacious in improving obstructive urinary symptoms.
Although it is clear that an increase in blood pressure above normal (> 130/85 mm Hg) is positively and linearly associated with morbidity and mortality, concerns have been expressed that reduction of blood pressure below a given threshold level may be linked to adverse outcomes. Some studies have shown an increase in mortality with blood-pressure reduction below a certain threshold, creating a J-shaped curve of mortality. The significance of these concerns remains controversial. Many of the studies that have suggested a J-curve relationship have been confounded by comorbid illnesses among those with the lowest blood pressures. However, the results from several longitudinal studies have identified an increased risk for stroke and overall mortality in persons in the lowest systolic and, particularly, diastolic blood-pressure levels. Until additional prospective data are available to provide guidance in this therapeutic dilemma, it is prudent to use caution in lowering blood pressure in older persons with hypertension much below 140/90 mm Hg. Excessive reductions in blood pressure (eg, diastolic levels below 70 mm Hg) and treatment-induced postural hypotension should be avoided.
The frequency of follow-up visits should reflect the patient’s degree of blood-pressure elevation at presentation, with closer follow-up indicated for those with more severe hypertension (ie, a systolic blood pressure greater than 180 mm Hg). With the exception of hypertensive emergencies (discussed below), attempts to reduce the patient’s blood pressure to target levels too rapidly are unnecessary and likely deleterious. For most patients, an interval of 1 to 2 months is appropriate between visits to determine the need for dose adjustment.
Given the age-related changes in systems that regulate blood pressure and impaired blood-pressure homeostasis, overtreatment of hypertension may result in situational (postural or postprandial) hypotension. At all follow-up visits, it is imperative to determine the supine and standing blood pressure (Table 46.4). It is good practice to adjust antihypertensive drug doses to achieve the target (seated) blood pressure only after determining whether postural hypotension is present.
The patient’s adherence to the current antihypertensive medication regimen should be assessed before an increased dosage is recommended or an alternative medication is considered. For some patients, additional information derived from blood-pressure measurements taken at home or another nonclinical setting may be important; home blood-pressure monitoring may also aid in promoting a patient’s adherence to therapy. Patient education regarding the significant benefits to be gained from adequate blood-pressure control is of particular importance, since hypertension is usually asymptomatic. The interdisciplinary geriatric team is well suited to promote this approach (eg, nurses to provide feedback on the degree of blood-pressure control, dietitians to review dietary information and adherence, pharmacists to promote adherence to the medical regimen, and social workers to review and, where possible, alleviate the financial burden associated with the cost of medical therapy). This evaluation should include a careful review of the patient’s other medications to identify those (eg, nonsteroidal anti-inflammatory drugs and corticosteroids) that may worsen blood-pressure control.
When a patient’s blood pressure has not been successfully reduced to the target level, cautiously increasing the dose, adding another agent (particularly a thiazide diuretic, if the patient is not already receiving this drug), or switching to another class of medication should be considered. Patients also should be counseled to continue their life-style modifications. It may take many months to achieve the target blood-pressure goal. When this goal is not attained despite adherence to a three-drug regimen, an evaluation for refractory hypertension (especially renovascular disease) should be considered. Once a patient has achieved appropriate stable blood-pressure control for more than a year, step-down treatment may be considered; a cautious downward dosage adjustment may be attempted, with close blood-pressure monitoring. Patients who have been successful at achieving weight loss or other nonpharmacologic interventions are most likely to be successfully weaned from antihypertensive medications.
Elevated blood pressure per se in the absence of signs or symptoms of target-organ damage does not constitute a hypertensive emergency or urgency. Rapidly and too aggressively reducing blood pressure in a patient with incidentally discovered elevated blood pressure is potentially harmful and may produce complications, such as coronary or cerebral hypoperfusion syndromes.
Examples of true hypertensive emergencies in older patients include hypertensive encephalopathy, acute heart failure with pulmonary edema, dissecting aortic aneurysm, and unstable angina. These situations present with symptoms and signs of vascular compromise of the affected organs. The management of these emergencies requires an acute hospital setting, with the parenteral administration of an antihypertensive agent and continuous blood-pressure monitoring to achieve an immediate reduction in blood pressure, although not initially to a normal target level. Blood pressure should not be lowered emergently more than 25% within the first 2 hours, with a goal of achieving 160/100 mm Hg gradually over the first 6 hours of therapy.
Hypertensive urgencies, situations in which blood pressure should be lowered within 24 hours to prevent the risk of target-organ damage, are more common than true emergencies. The majority may be managed with oral administration of antihypertensive medications to achieve a gradual blood-pressure reduction.
Approximately one third to two thirds of residents in long-term-care facilities have hypertension. Special considerations are warranted in the care of residents with respect to making the correct diagnosis and defining the goals of therapy and its effects on quality of life. Blood-pressure measurements in long-term-care settings may not be accurate. Inaccuracies result from measurement errors and from the temporal variability in blood pressure, particularly in relation to meals. Blood pressure appears to be highest in the morning before breakfast. Postprandial hypotension is common among long-term-care residents, affecting about one third of this population. The presence of postprandial hypotension has been associated with otherwise unexplained syncope, and it has been found to be a significant independent risk factor for falls, syncope, stroke, and overall mortality.
There are several factors to consider in the management of hypertension in this setting. First, the advanced average age of persons in long-term care raises controversy surrounding the question whether the benefits of antihypertensive therapy extend to the very old (ie, those aged 80 years and older). If the beneficial effects of treatment are less evident, the potential adverse effects and risks of therapy should be weighed more heavily in defining the goals of therapy. Even an intervention as seemingly innocuous as a sodium-restricted diet needs to be evaluated in the context of the high prevalence of protein-energy malnutrition among nursing-home residents. Second, the average resident in long-term care takes seven medications, and most have three or more comorbid conditions. The addition of an antihypertensive medication increases the possibility of an adverse drug event in this frail, at-risk group. Third, several studies have identified the use of antihypertensive medications, particularly vasodilators, as a risk factor for falls in this high-risk population, who experience an average of two falls each year. It is therefore important to assess both postural and postprandial blood pressure in this population. Randomized controlled trials that could provide clear risk-benefit evidence to support an approach to antihypertensive management in the long-term-care population have not yet been conducted. The available data suggest that diuretic therapy is effective in controlling systolic blood-pressure elevations and that blood-pressure reduction with diuretics lowers the prevalence of postural hypotension.
■ Chobanian AV, Bakris GL, Black HR, et al. The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure; The JNC 7 Report. JAMA. 2003;289(19):2560–2572. Available at http://www.nhlbi.nih.gov/guidelines/hypertension (accessed October 2005).
A concise treatment algorithm applicable to older hypertensive patients is presented in this update of the comprehensive recommendations of the National High Blood Pressure Education Program. A classification of prehypertension—systolic blood pressure 120 to 139 mm Hg—was added to emphasize the importance of early initiation of life-style modifications in the prevention of cardiovascular disease. The report emphasizes the implications of the aging of our population by pointing out that 90% of people who are normotensive at the age of 50 years will develop hypertension in their lifetime (see Vasan et al., discussed below, for more information on this topic). The primary treatment goal is to reduce systolic blood pressure to less than 140 mm Hg since systolic blood pressure confers greater risk than diastolic, and since the diastolic blood pressure will likely also achieve a level of less than 90 mm Hg as the systolic level is reduced. With respect to drug treatment, thiazide-type diuretics remain the preferred initial drug choice for most patients. This report emphasizes that for most patients, more than one antihypertensive drug is often needed to achieve the goal blood pressure, and that for stage 2 hypertension (systolic blood pressure greater than 160 mm Hg), two drugs—one of which is a thiazide-type diuretic—should be started at the outset of therapy. Beyond this, an individualized approach to therapy based on the patient’s risk factors and comorbidities is emphasized.
■ Domanski MJ, Davis BR, Pfeffer MA, et al. Isolated systolic hypertension: prognostic information provided by pulse pressure. Hypertension. 1999;34(3):375–380.
This study analyzed baseline blood-pressure readings obtained in persons enrolled in the Systolic Hypertension in the Elderly Program (JAMA 1991;265(24):3255–3264) and determined the independent relationships among systolic, diastolic, and mean blood pressure and the pulse pressure and the outcomes of stroke and death. In this population, higher pulse pressure was due to a combination of higher systolic and lower diastolic blood pressure. Using a Cox proportional hazards model that adjusted for the significant univariate predictors, including mean arterial blood pressure, the authors identified pulse pressure as an independent significant predictor of both stroke and overall mortality. An increase of 10 mm Hg in pulse pressure was found to be associated with an 11% increase in the risk of stroke and a 16% increase in mortality. These findings supplement the observation from other studies that identified the importance of systolic blood pressure as the more significant prognostic indicator than diastolic blood pressure. Since pulse pressure provides a surrogate indicator of arterial stiffness, these findings suggest that decreased arterial compliance and the resultant increase in both systolic and pulse pressure is of major pathophysiologic significance in older persons with hypertension.
■ Psaty BM, Lumley T, Furberg CD, et al. Health outcomes associated with various antihypertensive therapies used as first-line agents: a network meta-analysis. JAMA. 2003;289(19):2534–2544.
This study reports results of a network meta-analysis of 42 randomized controlled trials (including the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial [ALLHAT] and the Second Australian National Blood Pressure study [ANBP2]) to address the relative benefits of seven treatments (including placebo) with respect to cardiovascular outcomes and mortality. In this analysis, therapy with low-dose diuretics was found to be effective in comparison with placebo for all outcomes. In addition, diuretic therapy was better for all outcomes in comparison with β-blockers, angiotensin-converting enzyme inhibitors, calcium channel blockers, α-blockers, and angiotensin-receptor blockers. Although this analysis did not report findings specific to older hypertensive patients, many of the randomized controlled trials were conducted primarily in older patient populations such that these results should apply to geriatric hypertension. These findings underscore the recommendation that low-dose thiazide-type diuretics be used as the first-step antihypertensive for older patients with hypertension.
■ The ALLHAT Collaborative Research Group. Major outcomes in high-risk hypertensive patients randomized to angiotensin-converting enzyme inhibitor or calcium channel blocker vs. diuretic. JAMA. 2002;288(23):2981–2997.
This study was designed to determine the optimal initial antihypertensive drug for persons aged 55 years and older at risk for cardiovascular disease on the basis of age and one or more additional cardiovascular risk factors. The mean age of the 33,357 subjects was 67 years; about one third were black and one fifth Hispanic, and one third had diabetes mellitus. Subjects were randomized in double-blind manner to receive chlorthalidone, amlodipine, or lisinopril. (The α-blocker doxazosin arm was prematurely closed because of an excess of hospitalizations for heart failure in those subjects in comparison with the chlorthalidone group.) The chlorthalidone-treated group achieved a greater reduction in blood pressure than the other two groups. The primary outcome (fatal coronary heart disease or nonfatal myocardial infarction) did not differ between groups. The chlorthalidone group had lower rates of many secondary outcomes (lower heart failure rates than in the amlodipine group, and lower rates of cardiovascular disease, stroke, and heart failure than in the lisinopril group). These findings were similar for analyses conducted in subjects older than 65 years of age. The results from this trial reinforce the recommendation that thiazide-type diuretics be used as the first step in antihypertensive therapy.
■ Vasan RS, Beiser A, Seshadri S, et al. Residual lifetime risk for developing hypertension in middle-aged women and men. JAMA. 2002;287(8):1003–1010.
This study examined the risk of developing hypertension using Framingham study data from individuals who were normotensive at the time they entered the study when they were between 55 and 65 years of age. In this cohort, the residual lifetime risk of developing hypertension (defined as a blood pressure in excess of 140/90 mm Hg or the initiation of antihypertensive therapy) was 90%. These findings underscore the enormously high prevalence of hypertension among older persons. More than half (range 52% to 72%) of the residual lifetime risk for developing hypertension in these subjects who were between 55 and 65 years of age at study entry occurred within the first 10 years of follow-up. These results suggest that major public health initiatives should be directed toward the primary prevention of hypertension in this high-risk population.
■ Wing LM, Reid CM, Ryan P, et al. A comparison of outcomes with angiotensin-converting–enzyme inhibitors and diuretics for hypertension in the elderly. N Engl J Med. 2003;348(7):583–592.
The Second Australian National Blood Pressure study (ANBP2) was conducted in 6083 subjects aged 65 to 84 years who were randomized in an open-label design to treatment with either an angiotensin-converting–enzyme (ACE) inhibitor or a thiazide-type diuretic. In addition to being older (mean age 72 years), other differences in the subject population in comparison with the ALLHAT population were that 95% were white, and their blood pressure at entry was much higher (mean 167/91 mm Hg). The two treatment groups achieved comparable reductions in blood pressure. The group treated with ACE inhibitors had a lower incidence of primary end points of all cardiovascular events or all-cause death and myocardial infarction. These differences were evident only in men, in whom the event rate was twice as high as in women. There was no difference in the incidence of cerebrovascular events or stroke between the two treatment groups, except that the rate for fatal stroke was higher in the ACE inhibitor group. These findings demonstrate that, depending on the outcome being examined, ACE inhibitor therapy may offer benefits relative to thiazide-type diuretics, but that the treatment difference may apply only to men.
Mark A. Supiano, MD