If you thought you had your heart and stroke risk all figured out, a new study will have you reconsidering. Researchers have recalculated how risk factors, like weight and blood pressure, actually affect our risk of heart problems. The findings may make your heart sink just a bit, but fortunately, many of the risk factors are largely within our control. So the study empowers us as well as providing a sobering look at what puts hearts at risk.
Just a tiny change in any of the risk factors raised one’s risk considerably. For example, if all factors are ideal for a given person, but cholesterol is between 180 and 199 (not high enough to be treated, but still higher than ideal), one’s lifetime risk goes up.
The study followed 250,000 black and white participants of both sexes over a landmark 50 years. Most studies of this kind look at white males only, so the fact that this one included women and other ethnic groups gives it a lot more explanatory power than those in the past.
Cardiovascular risk factors like blood pressure, cholesterol, smoking, and diabetes status were measured when the participants were 45, 55, 65, and 75. The team tracked the likelihood of the participants experiencing a heart issue or stroke during their lifetimes.
"We are giving incomplete and misleading risk information if we only focus on the next 10 years of someone's life," said principal investigator Donald Lloyd-Jones. "With even just one risk factor, the likelihood is very large that someone will develop a major cardiovascular event that will kill them or substantially diminish their quality of life or health."
For example, a man who is 45 years old and has no risk factors has a 1.4% risk of having a heart attack or stroke. But the risk for a man with two or more risk factors goes up to 49.5%. For women, these numbers were 4.1% and 30.7%, respectively. Women are at higher risk for stroke, in general, but at lower risk for heart attack.
African-Americans have a greater risk for high blood pressure and diabetes than Caucasians, but their heart and stroke risk is similar to Caucasians because they also tend to have shorter lifespans overall.
"We need to do a much better job of making sure these risk factors don't develop in the first place, getting kids and young adults off to better starts so they don't gain weight and are following healthier lifestyles throughout their lives," Lloyd-Jones said. "It appears that the whole is greater than the sum of the parts.”
The study was carried out at Northwestern University, and published in the New England Journal of Medicine.