Heart disease, ocular health share important common ground in women

Ocular manifestations are an important component of heart disease, which kills more American women each year than all cancers combined.

Heart disease is the No. 1 killer of women in this country, and women and their ophthalmologists should understand the importance of cardiovascular health, especially the ocular implications.

“I think we’re all aware that the eye really can be the first manifestation of systemic disease, whether it be cardiovascular disease or other systemic diseases,” Ivana Kim, MD, said. “Most of us are already in the mindset that the eye is not separated from the rest of the body and the eye is unique in that that’s one of the only areas where we can actually directly visualize blood vessels.”

These fragile vessels, especially those in the highly vascularized retina, can easily become damaged from hypertension, or fall prey to vein occlusions or age-related macular degeneration – all overlapping with cardiovascular complications.

Studies have shown that women are more likely than men to show arteriolar narrowing with an increased risk for secondary ocular vascular complication and possible vision loss. Theoretically, this is due to a more prominent microvascular role in the development of coronary heart disease in women than men, and those with the narrowest retinal vasculature would have twice the risk.

These changes, as well as early signs of hypertension, can be seen by ophthalmologists when examining the retina, giving them a role in the diagnosis and management of cardiovascular disease.

“If we saw significant changes suggestive of hypertension, then I would make sure that the patient was aware, first of all, what their blood pressure was, whether or not they had been diagnosed with hypertension,” Dr. Kim said.

If the patient knows his or her blood pressure, Dr. Kim said she inquires whether it is under good control. If the patient does not know his or her blood pressure, an appointment should be made with the primary care physician to monitor the hypertension.

“I’m always in communication with the patient’s primary care doctor,” Dr. Kim said. “I would communicate with the doctor directly, too, saying that we found changes in the fundus suggestive of hypertension and point it out as a warning sign.”

Hypertension

Hypertension, a general cardiovascular disease, can have repercussions throughout the body, including the eye.

“In general, hypertension can predispose you to having a variety of eye problems,” Dr. Kim, a retinal specialist, explained. “It may be as minimal as changes in the appearances of retinal vessels that can be an indication of high blood pressure – even in patients who may not know they have high blood pressure – but changes like that don’t necessarily affect your vision.”

Even in the early stages of hypertension, it is possible for ophthalmologists to observe changes in vasculature in their patients. They can see various arteriolar vessel changes, including how they cross one another, become narrower or nicked, or create infarcts in the retina.

“If hypertension gets extremely out of control, then it can affect the retinal blood vessels to the point where vision is affected,” Dr. Kim said. “Those cases are rare. You really have to have severely elevated blood pressures and fairly acutely elevated blood pressures to have that.”

Retinal vascular occlusions

Dr. Kim said that chronic hypertension can predispose one to other eye conditions such as retinal vein occlusions.

“Hypertension causes retinal arteriolar changes that lead to compression of the veins at the A-V crossing, resulting in branch retinal vein occlusions,” she said.

Central or branch retinal artery or vein occlusions can be accompanied by hemorrhages, optic nerve atrophy and sometimes vision loss.

Vision loss subsequent to retinal arteriolar occlusions is caused by retinal ischemia, Dr. Kim said. Retinal vein occlusions can cause vision loss stemming from ischemia or macular edema.

“Narrowing of the carotid artery caused by atherosclerotic plaque that can predispose you to stroke can also predispose you to have a blockage of a retinal arteriole, either central or branch, and can lead to vision loss,” Dr. Kim said. “It’s like having a stroke in the eye basically. It leads to vision loss due to loss of blood supply to an area of the retina.”

Shared risk factors for cardiovascular disease, AMD

In addition to obvious connections between hypertension and physical changes in the retina, Dr. Kim pointed out that cardiovascular disease and AMD have many of the same risk factors and preventive measures.

“For a long time we’ve felt there have been similarities between the risk factors for macular degeneration and heart disease,” she said.

While smoking tops the list of shared risk factors, Dr. Kim also pointed to data linking obesity, serum lipid levels and statin drugs to both AMD and heart disease. Obesity and high serum lipid levels can be risk factors, while the use of statin drugs has been shown in some studies to be a preventive measure for both cardiovascular disease and AMD. Other studies have disputed these findings, however, so the data are not conclusive.

“There are a lot of overlapping risk factors, and we’re finding that a lot of things that people recommend for lowering your risk of heart disease may also be good for lowering your risk of macular degeneration,” Dr. Kim said.

She added, “Dietary factors, such as intake of omega-3 fatty acids, which are good for your heart, also seem beneficial in terms of lowering your risk of macular degeneration.”

She explained that advanced age is an important risk factor for developing both cardiovascular disease and ocular diseases such as AMD. Women are more affected by diseases related to age, she said, because they tend to live longer.

“Although people are living in general longer, it seems that women live longer than men,” Dr. Kim said.

Importance of a healthy lifestyle

Aside from AMD, heart disease and ocular health overlap in other ways as well.

“When we think about heart disease, we think mainly about the risk factors for heart disease,” Dr. Kim explained. “Eye disease and heart disease share a lot of common risk factors.”

Primarily, smoking and poor diet are two risk factors that can adversely affect both cardiovascular and ocular health. Modifying one’s diet and stopping smoking are good preventive measures.

“The message that we tell our patients when they ask what can they do to keep their eyes healthy is the same as what their primary care doctors are recommending to keep their heart healthy: Exercise, try to avoid obesity, don’t smoke,” Dr. Kim said. “If you have diabetes, make sure it’s under good control, eat a healthy, balanced diet, lots of fruits and vegetables, omega-3 fatty acids.”

Ocular health and optimal functioning of the microvasculature in the eye rely heavily on receiving appropriate nutrients from the heart.

A diet rich with fruits, vegetables, soluble fiber and soy provides phytosterols, phytochemicals and isoflavones that can help lower cholesterol and maintain good blood flow through the eye vessels.

“Everything that they’re hearing from their internist, we would probably reiterate,” Dr. Kim said. “I think to have that reinforced from all different perspectives is probably the bottom line.”

For more information:

• Ivana Kim, MD, can be reached at Retina Service, Massachusetts Eye and Ear Infirmary, Harvard Medical School, 243 Charles St., Boston, MA 02114; 617-573-3367; fax: 617-573-3678; e-mail: ivana_kim@meei.harvard.edu.

• Katrina Altersitz is an OSN Staff Writer who covers all aspects of ophthalmology.