Dear Dr. Roach: I am an 80-year-old active male taking only thyroxine. I have no known health issues. In November 2021, I experienced a migraine with aura and have a slight vision loss in my right eye. After seeing an eye doctor, a retinal specialist and a primary care doctor, the only thing I am hearing is the term “microvascular disease.” This is based on the eye doctor’s examination. I am unable to find a satisfactory definition or prognosis anywhere I search. Any information you could provide would be appreciated.
Dear R.B.: The blood vessels in your body go from very large (the aorta, which takes the blood directly from the heart, is the largest) all the way down to the capillaries, the very smallest. Microvascular disease refers to poor flow in the smaller arteries, called the arterioles. These branch off from the larger arteries and ultimately provide blood to the capillaries.
All organs have small blood vessels, but the term microvascular disease is most often applied to the heart and brain. The most common causes include smoking, high blood pressure and diabetes, but high cholesterol and rheumatological diseases such as rheumatoid arthritis or systemic lupus are other causes. However, it’s not necessary to have any of these conditions, as the condition can affect apparently healthy older women and men.
Unlike macrovascular disease, where there are usually discrete cholesterol plaques, microvascular disease is a more diffuse process. Diagnosis of microvascular disease of the brain is most commonly made by MRI. However, the retina is one place where brain blood vessels can be directly seen, and an ophthalmologist can see findings indicative of small vessel disease. Although most cases of migraine with aura are not related to microvascular disease, there is an association between migraine and microvascular disease. Given your relatively older age when your migraine developed, I would be concerned this might be the case in you.
Microvascular disease, as seen by eye exam or by MRI, increases your risk of a stroke. When I have a patient with this diagnosis, I am substantially more aggressive about treating risk factors, especially blood pressure and cholesterol. This may include medication treatment even if the numbers are not as elevated as would normally be treated with medicines. Of course, lifestyle changes, including a careful dietary history to identify potentially improvable habits, are critical as well. Smoking must be stopped if present, and careful control of diabetes has been proven to reduce risk. Even modest increases in regular exercise are important. Alcohol use should be no more than moderate, and minimal is probably better still.
The type of strokes associated with microvascular disease are different from strokes caused by blockages in big arteries to the brain. “Small” strokes, those that don’t cause immediate devastation, nonetheless can cause complications, including dementia, over time. These are what we want to prevent.
Of course, people can have both microvascular disease and macrovascular disease at the same time. Fortunately, the treatments for microvascular disease tend to help macrovascular disease, if present, as well.
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