dr. saver: the incidence of stroke approximately doubles for every decade over the age of 45. two-thirds of all strokes occur over the age of 65. but stroke is also not uncommon in mid-adult life, or even in childhood. and there are more strokes in patients under the age of 45 than there are cases of multiple sclerosis. the risk factors for stroke, in certain respects, resemble the risk factors for other cardiovascular diseases. dr. saver: high blood pressure, hypertension, is the number one modifiable risk factor for stroke. high blood pressure increases the risk of stroke fivefold compared to people who don't have high blood pressure. the conventional definition for high blood pressure is having a systolic blood pressure-- the upper number-- that's 160 or higher, and the diastolic blood pressure, or lower number, that's 85 or 90 or higher. if you have blood pressure in that range, then to work with your physician in lowering the blood pressure. usually the first steps are lifestyle changes: d