A surprising new way to assess women’s heart health

There’s been a lot of talk lately about women and heart disease. In newspaper columns, popular magazines – even on Oprah – people are talking about how this deadly disease kills more women than it does men. Much of the focus is on how women’s hearts are different from men’s – and how they may experience a different set of warning signs. And when women – and their doctors – don’t recognize those signs, it can be a recipe for disaster.

An important new study published in this week’s issue of the Journal of the American Medical Association reveals one way that doctors might better assess a woman’s true risk. Through an analysis of more than 9,000 women and men, scientists found that tiny arteries in the eyes can yield a surprisingly accurate view of women’s heart health.
How your eyes could reveal hidden heart risks

The research was part of the Atherosclerosis Risk in Communities Study (ARIC), an ongoing cohort of more than 15,000 people recruited from four communities in different parts of the U.S. The ARIC participants were originally enrolled between 1987 and 1989, and underwent examinations at baseline, three years after enrollment, and six years after enrollment.

The examinations captured a wide variety of health data, including blood pressure, glucose levels, lipid levels, waist-to-hip ratio, level of physical activity, smoking and drinking habits, and use of hormone replacement therapy. At the third exam, retinal photographs were also taken.

Using a high-resolution scanner, the photos were digitized to allow researchers to measure the diameters of the tiny arteries (called arterioles) and veins (called venules) in the retina. They summarized the findings from each photograph in an arteriole-to-venule ratio, referred to as AVR. A smaller AVR value indicated narrower arterioles.

For this analysis, the researchers excluded participants who had existing coronary heart disease (CHD) at baseline, or who had been diagnosed with CHD before the third examination. Then three years after the retinal photographs were taken, they followed up with the 9,648 eligible participants, and assessed their heart health.
Study shows heart disease in women takes a different path

Here’s what they found: women in the lowest AVR quintile were more than TWICE as likely to have had a heart attack, coronary angioplasty, or bypass procedure during the three-year follow-up period than women in the highest quintile. For every one standard deviation decrease in AVR, a woman’s risk jumped 37 percent. The association held fast even after controlling for age, race, and HRT use, and was seen for women with and without diabetes and hypertension. Interestingly, AVR was not associated with the heart disease risk in men at all.

As the authors note, these findings support the idea that women’s coronary heart disease may be more about microvascular processes (the part of the circulatory system composed of the smallest vessels, like capillaries, arterioles, and venules) than the macrovascular processes (like arteries and veins) that doctors typically look for. This may explain why women often complain of chest pain yet show no blockage in the coronary arteries, why women more often die after a heart attack than men, and why women fare worse after bypass surgery.

The authors explain that it used to be difficult to assess microvascular health, as the assessment methods were invasive and impractical for widespread use. But this study suggests that retinal photography may provide a non-invasive, accessible – and accurate – way to assess women’s true cardiovascular health.

You may have had retinal photographs taken before without even knowing it; for most ophthalmologists, it’s a regular part of a routine visit. But if you’re a woman concerned about heart disease, and you haven’t seen your ophthalmologist for a while, maybe it’s time to make another appointment. This time, ask the doctor about your AVR value – and be sure to share those results with your physician.

Source: JAMA 2002;287:1153-1159

Copyright 1997-2002 by Institute of Health Sciences, L.L.C.