Systolic blood pressure increases sharply with age in people in Western societies (Figure 3.14). There is a lesser increase in diastolic pressure. Thus pulse pressure increases with age.
Thus, instead of the usual blood pressure of 120/80 seen in younger individuals, with is a pulse pressure of 40, blood pressures of 160/90 may be seen, with a pulse pressure of 70. The increase in pulse pressure is another expression of the age-related decrease in arterial compliance.
The increase in diastolic blood pressure is not primarily a function of the change in compliance of the vessel wall, but is rather due to the increased resistance of the arterial tree.