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High Blood Pressure
Pages 33-52

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From page 33... ... are strong predictors of subsequent cardiovascular disease in the el~er~y.38 In the past two years there has been an explosion of new knowledge on the epidemiology, pathophysiology, and treatment of high blood pressure in older in~ivi~uais.7 Because the risk of future cardiovascular morbid and mortal events rises in a continuous fashion as either systolic blood pressure or diastolic blood pressure rises, there is no threshold of either systolic or diastolic pressure that can be described definitively as hypertensive.40 Nonetheless, for operational purposes, this chapter will use the following definitions based on clinical conventions and on recommendations issued in 1985 by a National Heart, Lung and Blood Institute advisory committee (the Subcommittee on Hypertension Definition and Prevalence) Read the entire page →
From page 34... ... However, data from the Framingham longitudinal research and other studies indicate that not all individuals experience an aging-related increase in blood pressure.38 In addition, population studies from nonindustriaTized societies indicate that average blood pressure among such groups does not tend to rise with age.S1 Estimates of the true prevalence of high blood pressure vary greatly depending on the age and race of the population, the blood pressure level used to define hypertension, and the number of measurements made.~5 The prevalence of both systolic/diastolic high blood pressure and isolated systolic high blood pressure is considerable in persons over the age of 50. Because levels of diastolic blood pressure tend to level off around age 55, the prevalence of systolic/ diastolic high blood pressure tends to be constant for persons aged 50 and older.25 Therefore, although some authors speak in general terms of the rise in prevalence of high blood pressure with age, the prevalence of systolic/diastolic high blood pressure rises little with age.50 Actually, it is the rise in isolated systolic high blood pressure that accounts for most of the overall increase; the prevalence of systolic/diastolic high blood pressure in persons over the age of 50 is about 15 percent in whites and 25 percent in blacks.33 The prevalence of isolated systolic high blood pressure varies with increasing age from 1 or 2 percent at age 50 to greater than 20 percent over age 8032 50 57 and does not appear to differ according to race. Read the entire page →
From page 35... ... Nonetheless, it appears that the number of new incidence cases of isolated systolic high blood pressure continues to increase in persons over age 55. Although the clinical treatment of high blood pressure has cIassically focused on diastolic blood pressure levels, epidemiologic data indicate that, for middle-aged and older adults, the systolic blood pressure level is more predictive of future cardiovascular morbidity and mortality.~337 Both systolic pressure and diastolic pressure, however, remain independently predictive of future vascular events. Read the entire page →
From page 36... ... 7 Actually, the overall pathophysiology of high blood pressure in black and elderly persons exhibits a similar profile.7 44 73 Both black and elderly hypertensives tend to be sodium sensitive and have low renin levels, as well as increased vascular resistance. It has been suggested that black hypertensives are particularly likely to conserve sodium with expansion in extracellular volume and consequent development of high blood pressure.44 73 UTILITY OF SCREENING Several studies have shown that the casual office blood pressure measurement is strongly predictive of subsequent cardiovascular and cerebrovascular events.37 Yet recent analyses of data collected in a national multicenter clinical trial (the Hypertension Detection and Follow-up Program) Read the entire page →
From page 37... ... Currently, it would appear that multiple office blood pressure measurements or, in selected situations, ambulatory blood pressure measurements are highly predictive of subsequent cardiovascular risk. Therefore, office or ambulatory blood pressure monitoring is sufficiently sensitive and specific as a screening test for true high blood pressure. Read the entire page →
From page 38... ... Treatment appeared to be effective for persons with entry systolic blood pressure from 160 to 239 mmHg, but the treatment did not appear to have an impact on participants with entry diastolic blood pressure in the range 90 to 95 mmHg.4 The reduction in endpoints seen in the intervention group disappeared in persons over the age of 80, suggesting that treatment might not be effective in persons of advanced age. However, the number of participants aged SO and older was small, and these subgroup data thus are not definitive. Read the entire page →
From page 39... ... 161. bDBP = diastolic blood pressure; SBP = systolic blood pressure. Read the entire page →
From page 40... ... . Evidience That Treatment of Isolatedt Systolic High Blood Pressure is Beneficial To date there are no data from randomized controlled trials to demonstrate that treatment of isolated systolic high blood pressure Read the entire page →
From page 41... ... the study cited may have had too short a duration to demonstrate a benefit in terms of the natural history of coronary heart disease; (2) some of the subjects in the studies may have experienced too vigorous a lowering of diastolic blood pressure, which may have adversely affected coronary artery blood flow, particularly to the subendocardial layer cluring diastole;20 or (3) Read the entire page →
From page 42... ... .9 There is good evidence to indicate that the baroreceptor reflex becomes less sensitive with age.28 4i As a result, the elderly could be more sensitive to the postural hypotensive effects of antihypertensive medications, with a consequent increased propensity for falls and fractures.~4 Although some have argued that elderly persons with high blood pressure actually need higher blood pressure for adequate perfusion of vital organs (e.g., the brain and kidney) ,35 most studies have not shown that judicious use of antihypertensive medications in the elderly has a significant adverse effect on either renal or cerebral perfusion.~25568 It is clear from the work of Strandgaard that in middle-aged patients with chronic essential hypertension the pressureflow curve for cerebral autoregulation is reset to the right. Read the entire page →
From page 43... ... The largest available data set on the toxicity of antihypertensive therapy in the elderly comes from the European Working Party on Hypertension in the Elderly and its randomized study of the efficacy of the treatment of systolic/diastolic high blood pressure in a cohort of patients with a mean age at entry of 72 years.4 Early reports from this trial indicate that treatment with a thiazide-triamterene combination (followed by alphamethyIdopa as a second-step agent when needed) resulted in mild increases in glucose intolerance, serum creatinine, and uric acid and a mild decrease in serum potassium in the treatment group.2 Treatment floes not appear to have had a significant long-term effect on serum cholesterol levels.5 To date, only limited data on side effects have been reported, but there was no significant difference between the treatment and control groups in the rate at which patients were dropped from the study because of presumed drug-related side effects. Read the entire page →
From page 44... ... NONPHARMACOLOGIC THERAPY Nonpharmacologic therapy, including weight loss, sodium restriction, moderate consistent aerobic exercise, and relaxation therapy all may be helpful in individual patients, particularly those with borderline elevations of blood pressure.40 Unfortunately, the only available studies of the efficacy of these measures have been conducted in young to middle-aged patients. Currently, data indicate that, if the patient is overweight, moderate weight loss is the most effective nonpharmacologic treatment for high blood pressure, although questions remain regarding the efficacy of weight Toss because many patients regain the lost weight over an extended period of time. Read the entire page →
From page 45... ... Further analysis showed that, in the population treated, there was a 45 percent reduction in stroke incidence.~� SUMMARY In conclusion, systolic/diastolic high blood pressure and isolated systolic high blood pressure are sufficiently prevalent to be considered important risk factors in persons over the age of 50. In addition, epidemiologic studies indicate that both systolic blood pressure elevations and diastolic blood pressure elevations are significant independent risk factors for subsequent cardiovascular and cerebrovascular morbidity and mortality; however, elevation of systolic Read the entire page →
From page 46... ... Current data from randomized controlled clinical trials indicate that the treatment of moderate to severe diastolic high blood pressure in the elderly is, indeed, warranted; treatment of mild diastolic high blood pressure in the elderly should be left to the judgment of individual clinicians and patients. The data are too limited at present to make a definitive statement about the treatment of isolated systolic hypertension. Read the entire page →
From page 47... ... 3. For patients with systolic blood pressure greater than 160 mmHg and diastolic pressure less than 90 mmHg, physician discretion should be used regarding therapy. Read the entire page →
From page 48... ... Efficacy of antihypertensive drug treatment according to age, sex, blood pressure, and previous cardiovascular disease in patients over the age of 60. Lancet 1986; 1 :589-592. Read the entire page →
From page 49... ... R Electrocardiographic left ventricular hypertrophy and risk of coronary heart disease. Read the entire page →
From page 50... ... H The effects of drug treatment for hypertension on morbidity and mortality from cardiovascular disease: A review of randomized trials. Read the entire page →
From page 51... ... M Mortality associated with diastolic hypertension and isolated systolic hypertension among men screened for the Multiple Risk Factor Intervention Trial. Read the entire page →
From page 52... ... Determinants of isolated systolic hypertension. Journal of the American Medical Association 1988; 260:3451-3455. Read the entire page →

From page 33...

... are strong predictors of subsequent cardiovascular disease in the el~er~y.38 In the past two years there has been an explosion of new knowledge on the epidemiology, pathophysiology, and treatment of high blood pressure in older in~ivi~uais.7 Because the risk of future cardiovascular morbid and mortal events rises in a continuous fashion as either systolic blood pressure or diastolic blood pressure rises, there is no threshold of either systolic or diastolic pressure that can be described definitively as hypertensive.40 Nonetheless, for operational purposes, this chapter will use the following definitions based on clinical conventions and on recommendations issued in 1985 by a National Heart, Lung and Blood Institute advisory committee (the Subcommittee on Hypertension Definition and Prevalence)

High Blood Pressure Pages 33-52

High Blood Pressure
Pages 33-52