What is isolated systolic hypertension?
Isolated systolic hypertension (ISH) is defined as elevated systolic blood pressure in conjunction with normal diastolic blood pressure (<90 mm Hg). Previously, systolic pressure of more than 160 mm Hg was classified as ISH, and pressure between 140 and 160 mm Hg was classified as borderline ISH. In 1993 the definition of ISH was changed to any systolic blood pressure above 140 mm Hg together with diastolic blood pressure below 90 mm Hg. ISH is characterized by an increased pulse pressure, defined as the difference between the systolic and diastolic blood pressures.
