The variation in pressure in the left ventricle (blue line) and the aorta (red line) over two cardiac cycles ("heart beats"), showing the definitions of systolic and diastolic pressure. A recent classification recommends blood pressure criteria for defining normal blood pressure, prehypertension,<unk>  (stages I and II), and isolated systolic<unk> , which is a common occurrence among the elderly. These readings are based on the average of seated blood pressure readings that were properly measured during 2 or more office visits. In individuals older than 50 years,<unk>  is considered to be present when a person's blood pressure is consistently at least 140 mmHg systolic or 90 mmHg diastolic. Patients with blood pressures over 130/80 mmHg along with Type 1 or Type 2 diabetes, or kidney disease require further treatment. Classification Systolic pressure Diastolic pressure mmHg kPa (kN/m2) mmHg kPa (kN/m2) Normal 90–119 12–15.9 60–79 8.0–10.5 Prehypertension 120–139 16.1–18.5 80–89 10.8–11.9 Stage 1 140–159 18.7–21.2 90–99 12.0–13.2 Stage 2 ≥160 ≥21.3 ≥100 ≥13.3 Isolated systolichypertension ≥140 ≥18.7 <90 <12.0 Source: American Heart Association (2003). Resistant<unk>  is defined as the failure to reduce blood pressure to the appropriate level after taking a three-drug regimen. Guidelines for treating resistant<unk>  have been published in the UK, and US.
Essential hypertension
Benign hypertension
Secondary hypertension
Paroxysmal hypertension
Renovascular hypertension
White coat hypertension
Labile hypertension
Systolic hypertension