Isolated systolic hypertension (ISH) indicates that only the systolic blood pressure (the top number of a blood pressure reading) is elevated. ISH occurs mainly in older people because systolic pressure increases with age, whereas diastolic pressure can decline after age 55.

ISH patients have a rise in systolic pressure (above 140) but diastolic pressure remains normal. ISH is a common cause of stroke, and some studies suggest that it is probably a more important cause of stroke and heart attack than diastolic hypertension.

Until the year 2000, high blood pressure was generally diagnosed by paying attention to people’s diastolic blood pressure. For this reason, some people believe that a larger number of ISH cases may have gone undiagnosed.

Malignant, or accelerated, hypertension occurs in less than 1 percent of hypertensive patients. It is defined as a sudden rise in diastolic blood pressure to over 120. This very high diastolic blood pressure can be associated with damage to the brain, heart, eyes and kidneys.

The condition is considered life threatening, and immediate medical attention is extremely important. Treatment generally requires intensive care hospitalization with potent medications delivered through an intravenous (I.V.) line to take effect as quickly as possible. Symptoms include loss of vision, nausea, drowsiness, confusion and headache.

Resistant hypertension is high blood pressure that does not respond to typical treatments and therapies. Because of this, it is difficult to control and often requires lifestyle changes and two or three medications. People with resistant hypertension are urged to work closely with the physician who manages their condition and to carefully follow all of the physician’s orders regarding diet, exercise and medications.