Eyes Help Predict High Blood Pressure
Blood Vessels in Eyes May Indicate Future High Blood Pressure
Aug. 9, 2004 -- Want to know if you're likely to develop high blood pressure? The answer may lie in your eyes.
Color, size, and shape don't matter. Nor does quality of eyesight.
Instead, it's tiny blood vessels, called retinal arterioles, that count. The vessels, found in the retina, can be photographed with special cameras.
The slightest changes in the vessels can indicate who's going to develop high blood pressure, also known as hypertension, within five years.
The finding is based on the Blue Mountains Eye study of more than 3,600 people living in the Blue Mountains west of Sydney, Australia. All were at least 49 years old.
Researchers started by interviewing participants, taking their blood pressure, and photographing their retinas. Normal or high-normal blood pressure was recorded in 1,032 people, while 950 had mild high blood pressure and 1,645 had severe high blood pressure.
Five years later, those with normal to mild high blood pressure were invited back for follow-up tests. Of the 1,319 who showed up, 390 had developed severe high blood pressure. That's almost 30% of the group.
Next, researchers compared the retinal photos of participants who had developed severe high blood pressure with those who hadn't.
The people who had developed severe high blood pressure were significantly more likely to have had narrowed blood vessels in the initial eye photographs, especially if they were less than 65 years old when the images were taken.
"Our findings support the hypothesis that small vessel structural changes may precede the development of severe high blood pressure," write the researchers in the journal Hypertension.
The results were in line with those recently reported in a similar study.
Changes in the blood vessels' walls were also associated with inflammation. "This is consistent with recent studies that suggest inflammation may also play a role in the development of hypertension," write the researchers.
Doctors commonly examine the blood vessels in the retina by shining a light in the eye. However, putting this study's findings to use is a bit more complicated than that and could be helped by creating new technology. The researchers call for the development of automated methods to better quantify abnormalities seen in retinal blood vessels.
SOURCE: Hypertension, October 2004. News release, American Heart Association.