What causes diastolic blood pressure to be higher than systolic blood pressure?

Diastolic pressure cannot be higher than systolic pressure. If diastolic pressure is high—especially if it exceeds systolic pressure—it likely indicates an error in measurement.

Blood pressure in the human body consists of systolic and diastolic pressure. Systolic pressure refers to the pressure exerted by blood against arterial walls when the heart contracts, while diastolic pressure is the pressure when the heart relaxes. Systolic and diastolic pressures are measured based on pulsations in the peripheral brachial artery. Systolic pressure should always be higher than diastolic pressure; it is extremely uncommon for diastolic pressure to exceed systolic pressure.

Both elevated diastolic and systolic pressures pose health risks. The primary danger of hypertension involves cerebrovascular complications, such as acute events like stroke, which may lead to conditions such as hemiplegia. Individuals with high diastolic pressure are often young or middle-aged adults who still have relatively elastic blood vessels. These patients may present with normal or low systolic pressure but elevated diastolic pressure, placing them at risk for target organ damage affecting the heart, brain, and kidneys. Active treatment is recommended.

Patients with abnormal blood pressure should monitor their levels regularly, avoid strenuous exercise, and refrain from long-term alcohol consumption.