High blood pressure (hypertension).

High blood pressure increases the risk of heart disease, a heart attack or a stroke. Although other risk factors can cause hypertension, it is possible to suffer it without having other risk factors.
Hypertensive people who are also obese, smoke, or have high blood cholesterol levels have a much higher risk of heart disease or stroke. Blood pressure varies according to activity and age, but a healthy adult at rest usually has a maximum systolic pressure of less than 120 and a minimum diastolic pressure of less than 80 mm Hg.