A Change of Heart
A new tool alerts women to their hidden risks of heart disease
There's grim evidence that methods of identifying and helping women at risk have fallen short. While men's death rates from heart trouble have been dropping for the past quarter century, women's have not. Every year since 1984, in fact, more women than men have died, with the most recent count standing at about 460,000 versus 400,000.
The new tool, described in last week's Journal of the American Medical Association, adds two new elements-family history and levels of C-reactive protein, a marker of inflammation that rises when there is blockage in the arteries-to the mix. "Family history turns out to be a very important predictor for women, perhaps more so than in men, so it's good to have it there," says cardiologist Sharonne Hayes, director of the Women's Heart Clinic at the Mayo Clinic in Rochester, Minn. The protein marker, a recent discovery, is a little more controversial because it hasn't been studied as extensively. But it's gaining more acceptance, says Roger Blumenthal, a cardiologist specializing in disease prevention at the Johns Hopkins University School of Medicine.
What Blumenthal really likes, though, is that the Reynolds score (so named because the calculator development was funded by the Donald W. Reynolds Foundation, which aims to prevent heart disease) predicts not just heart attacks but strokes and all the other cardiovascular problems that affect women more than men. "I think you get a much better picture of women's risks if you include these other things," Blumenthal says. "That's why this is really a landmark study."
In this study, Ridker's group followed about 16,000women for 10 years to determine which of 35 possible risk factors best signaled this broader range of heart problems. Once they identified the most powerful seven to create the Reynolds calculator, the researchers took an additional 8,000 women and ran them through both the Reynolds and the estimator developed by Framingham. About 600 of these women were classified by the older method as being at intermediate risk. But the newer system put about a quarter of those same women at higher risk and about another quarter at low risk. "With the high-risk women you can consider blood pressure medication or aspirin or statins," says Ridker. "And those at low risk you can tell not to worry."
Another new feature of the Reynolds calculator is that it allows women to project their risks up to 40 years in the future. "That's really important for a 40-year-old woman, for example, because typically we don't start seeing heart trouble until the mid-50s or later," Blumenthal says. "So if you just estimate risk at age 40, it doesn't look like there's any problem." But projecting it to age 60 makes the consequences jump out.
Motivation. For instance, a 45-year-old smoker with slightly elevated blood pressure and total cholesterol, slightly low "good" cholesterol, and a C-reactive protein reading that's a little high, has only a 4 percent chance of heart trouble during the next 10 years of her life, according to the Reynolds calculator. But at age 65, if none of these levels change, her risk jumps up to 20 percent. At age 75, it shoots up to 38 percent. "That could motivate one of my patients" to exercise or give up smoking, Mayo's Hayes says. "We all hear we should make lifestyle changes all the time, and we don't. But this might be another little piece of ammunition we can use."