Heart risk: the long and short of it.

Doctors trying to size up a person's risk of heart attack may soon look to height. A new study suggests that shortter men run a higher risk of heart attack than taller ones; last year, researchers reported a similar trend in women.

"Height is definitely associated with risk of heart attack," says epidemiologist Patricia Hebert of Harvard Medical School in Boston. She and her colleagues culled data from the Physicians' Health Study, an investigation begun in 1982 that has involved more than 22,000 male physicians between the ages of 40 and 84. Upon entering the study, each volunteer answered questions about his height and cardiac risk factors. During a five-year follow-up period, the researchers recorded 378 first heart attacks among the recruits. After controlling for smoking, high cholesterol levels and other factors known to increase the heart attack threat, the team discovered that the shortest men in the study (5 foot 7 or shorter) had more heart attacks than the tallest men (6 foot 1 or taller). Indeed, the risk of a first heart attack was 60 percent greater among the shortest men than among the tallest.

Hebert says she doesn't know why short stature seems to correlate with heightened heart risk, but she speculates that short people may have smaller blood vessels, which might increase the chance that a blood clot will lodge in the coronary arteries leading to the heart. Such a clot can precipitate a heart attack if it blocks a vessel already narrowed by plaque.

Hebert cautions, however, that short stature probably represents a relatively minor risk factor for heart attack. She advises short and tall people alike to concentrate on eating a low-fat diet, avoiding smoking, getting lots of exercise and making other heart-healthy lifestyle changes.