Diastolic hypertension in the absence of major risk factors and target organ damage is defined as diastolic blood pressure ≥90 mm Hg.
Systolic hypertension in the absence of major risk factors and target organ damage is defined as systolic blood pressure ≥140 mm Hg.
In the presence of normal diastolic blood pressure (<90 mm Hg), systolic hypertension is referred to as isolated systolic hypertension.
General Principles in Older Adults
Hypertension in older (and younger) adults is defined according to Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure VII (JNC 7) criteria as blood pressure (BP) >140/90 mm Hg based on the mean of two or more properly measured seated readings on each of two or more office visits.
Hypertension is very common among older adults. The prevalence of hypertension is as high as 63% in ages 60–79 years, and 74% in age ≥80 years. Hypertension is a major risk factor for cardiovascular and cerebrovascular morbidity and mortality. In 2008, 1 in 6 deaths were caused by heart disease and 1 in 18 deaths were caused by strokes in United States. Aging, higher body weight, smoking, reduced physical activity, and salt intake are major risk factors for hypertension.
In the presence of normal diastolic BP (<90 mm Hg), elevation in systolic BP is referred to as isolated systolic hypertension (ISH). Systolic pressure rises with age but diastolic pressure rises until about 55 years of age, and then gradually falls thereafter (Figure 30–1). Therefore, isolated diastolic hypertension is rare in the older adults. Diastolic hypertension, when present, usually occurs in combination with systolic hypertension in older adults (diastolic–systolic hypertension).
Changes in systolic blood pressure (SBP), diastolic pressure (DBP), and pulse pressure (PP) with aging. SBP and PP increase with age. DBP plateaus or peaks at approximately 55 years. Plotted using data from Framingham Heart Study.
Elevated pulse pressure (PP), which is systolic pressure minus diastolic pressure, is increasingly being recognized as an important predictor of cerebrovascular and cardiac risk in older adults. PP increases with age in a manner parallel to the increase in systolic BP.
“Longevity is a vascular question, which has been well expressed in the axiom that man is only as old as his arteries. To a majority of men death comes primarily or secondarily through this portal. The onset of what may be called physiological arterio-sclerosis depends, in the first place, upon the quality of arterial tissue which the individual has inherited, and secondly upon the amount of wear and tear to which he has subjected it.”
Sir William Osler, 1898
Hypertension in older adults is largely caused by increased arterial stiffness (collagen replacing elastin in the elastic lamina of the aorta), which accompanies aging. This leads to increased pulse wave velocity, ...