Men and women who developed high blood pressure in their middle age or who started out with high blood pressure have an estimated 30 percent increased risk of having a heart attack or stroke compared to those who kept their blood pressure low, according to a new study.
The new Northwestern Medicine research offers a new understanding on the importance of maintaining low blood pressure early in middle age to prevent heart disease later in life.
Previous estimates of a person's risk of cardiovascular disease were based on a single blood pressure measurement.
The higher the blood pressure reading, the greater the risk. The new Northwestern Medicine study expands on that by showing a more accurate predictor is a change in blood pressure from age 41 to 55.
"We found the longer we can prevent hypertension or postpone it, the lower the risk for cardiovascular disease," said lead author Norrina Allen, assistant professor of preventive medicine at Northwestern University Feinberg School of Medicine.
People that maintain or reduce their blood pressure to normal levels by age 55 have the lowest lifetime risk for a heart attack or a stroke.
The study used data from 61,585 participants in the Cardiovascular Lifetime Risk Pooling Project. Starting with baseline blood pressure readings at age 41, researchers measured blood pressure again at age 55, then followed the patients until the occurrence of a first heart attack or stroke, death or age 95.
Men who developed high blood pressure in middle age or who started out with high blood pressure had a 70 percent risk of having a heart attack or stroke compared to a 41 percent risk for men who maintained low blood pressure or whose blood pressure decreased during the time period.
Women who developed high blood pressure had almost a 50 percent risk of a heart attack or stroke compared to a 22 percent risk for those who kept their blood pressure low or saw a decrease.
Men generally have a 55 percent risk of cardiovascular disease in their lifetimes; women have a 40 percent risk.
The study is published in Circulation: Journal of the American Heart Association.