New tool refines heart risk prediction

For about 10 years, the Framingham risk score has been used to estimate a person's chances of having a heart attack based on just six bits of information -- age, sex, total cholesterol, HDL cholesterol, smoking status, and systolic blood pressure.

Doctors know what to recommend for people whose scores indicate high or low risk. But it's less clear what to do with those in the middle.

Over the years, researchers have experimented with adding additional risk factors to the formula to try to narrow the grey zone of mid-range results. Now, after testing three dozen separate risk factors, Harvard researchers have found that adding just two --a measurement of C-reactive protein and whether a parent had a heart attack before age 60 -- to the Framingham model made the resulting predictions even more accurate, reports the May 2007 issue of the Harvard Heart Letter.

Based on information collected from more than 24,000 women for more than a decade, the researchers created a new tool called the Reynolds risk score. When used on the study group, the Reynolds risk score did as well as the Framingham risk score for women at high and low risk. For those in between, it was better. The new model reclassified almost half of these women into high- risk and low-risk groups. The new assignments, done by computer, corresponded almost perfectly to what actually happened to these women over the next 10 years.

The team is now checking to see if the new risk tool works as well for men. The researchers have posted it at http://www.reynoldsriskscore.org/ for anyone to try.

Also in this issue: -- Heart scans hold promise -- New drug for blood pressure -- Decoding the latest diet trial -- Ask the doctor: Is weight lifting safe with a stent? Is my breathlessness a heart or lung problem? Can eye drops for glaucoma affect the heart?

The Harvard Heart Letter is available from Harvard Health Publications, the publishing division of Harvard Medical School, for $28 per year. Subscribe at http://www.health.harvard.edu/heart or by calling 1-877-649-9457 (toll free).