Isolated systolic hypertension is commonly associated with which mechanism?

• A. Commonly due to arterial stiffness in older adults.
• B. Caused by kidney disease.
• C. Defined by elevated diastolic pressure.
• D. Related to decreased arterial stiffness.

Answer: (A)

The key idea is that isolated systolic hypertension results from reduced elasticity of the large arteries, especially in older adults. When the aorta and other big arteries stiffen with age, they don’t dampen the pressure of the blood ejected by the heart. This causes the systolic pressure to rise (higher peak pressure with each beat) while diastolic pressure may stay the same or fall because the stiff vessels don’t recoil well to maintain diastolic flow. The combination produces a wide pulse pressure—high systolic, normal or low diastolic.

That’s why the statement about arterial stiffness in older adults is the best description. The other options don’t fit: kidney disease can cause hypertension but not the typical isolated systolic pattern driven by arterial stiffness; defining the condition by elevated diastolic pressure is inaccurate; and decreased arterial stiffness would actually lessen systolic pressure rather than raise it.