isolated systolic hypertension

Picture an old garden hose that has lost its springiness. A young, supple hose stretches a little with each pulse of water and cushions the surge; a stiff, sun-baked hose cannot, so the peak pressure shoots higher while the baseline barely changes. Isolated systolic hypertension is that pattern in arteries: the systolic (peak) number is high, but the diastolic (resting) number stays normal.

By definition it usually means a systolic pressure at or above about 130–140 mmHg with a diastolic below 80–90 mmHg, depending on the guideline. It is the most common form of hypertension in older adults and is driven mainly by arterial stiffening with age, which widens the gap between systolic and diastolic pressure (the pulse pressure).

It was once dismissed as a harmless consequence of aging, but large trials showed the opposite: treating it lowers the risk of stroke, heart failure, and death. The challenge is to bring the systolic number down without pushing the already-low diastolic pressure so low that blood flow to the heart and brain suffers, so treatment is individualized and monitored.