Effects of high blood pressure on visual health

17/05/2024

High blood pressure is a disease that represents a silent threat to the human body, as it can severely affect vital organs such as the brain, heart, kidneys and eyes without showing obvious symptoms until the damage is clinically evident.

The retina offers a unique window to directly observe the effects of high blood pressure on blood vessels, thanks to a simple, non-invasive technique called ophthalmoscopy. This technique allows for evaluation of eye damage and enables comparisons with the damage in other organs.

Hypertensive retinopathy encompasses a series of ocular manifestations that occur in the retina as a result of high blood pressure. The higher the blood pressure and its duration, the greater the probability of severe eye damage and, consequently, generalized damage to the body.

Several additional factors can aggravate hypertensive retinopathy, such as arteriosclerosis, advanced age, diabetes, high cholesterol and triglyceride levels, and tobacco consumption, among others.

The severity of retinopathy also depends on the pre-existing state of the retinal blood vessels and the rapidity of hypertension development. We can distinguish between two main variants:

Chronic hypertensive retinopathy

Most patients experience this variant and are initially asymptomatic but develop visual difficulties as hypertension progresses. It is often detected incidentally during a fundus examination, which may reveal findings such as reduced vascular calibre, pathological arteriovenous crossings, alterations in the vascular reflex and retinal aneurysms.

Acute hypertensive retinopathy, also known as malignant or accelerated

This form appears suddenly with very high blood pressures, accompanied by severe headache and significant visual loss. During clinical examination, retinal haemorrhages, soft and hard exudates, papilledema, and macula oedema can be observed.

There is no specific treatment for hypertensive retinopathy; however, it is crucial to strictly and continuously monitor blood pressure. While permanent eye damage and visual problems may persist in some patients with poor control, generally, a reduction in blood pressure usually results in significant improvement in retinal lesions.

Therefore, periodic ophthalmoscopic evaluations are recommended for all patients with arterial hypertension. These evaluations should be adapted according to the severity of the disease, the patient’s age, and the presence of other cardiovascular risk factors.

Dr. Sònia Viver, ophthalmologist at the Barraquer Ophthalmology Centre