Hypertensive retinopathy: causes, signs and treatments

Hypertensive retinopathy is a pathology related to blood pressure that can affect vision if it is not treated in time. Read on and learn how to diagnose, treat and prevent this disease.

Last update: October 01, 2021

In addition to possible heart and cerebrovascular problems, high blood pressure is also associated with hypertensive retinopathy. In this disease, the blood vessels of the retina are affected, which can cause damage to vision.

High blood pressure is one of the most common health problems in the world, affecting 1 in 5 people. Although the figure is higher in developed countries.

However, not all people with high blood pressure who may have hypertensive retinopathy are aware of the problem and the risks. An examination of the retina usually shows if you have this condition.

What is hypertensive retinopathy?

When blood pressure is high, the walls of the vessels are affected. This includes the arteries that supply the eye.

Over time, one of the consequences of high blood pressure in the body is that these blood vessels in the retina degenerate, causing vision problems. In this order of ideas, it is called Hypertensive retinopathy to the set of changes and alterations that take place in the eye by high blood pressure.

Symptoms of hypertensive retinopathy

The retina is a transparent tissue, very sensitive to light, that is in the center and behind the eyeball. Its function is to receive the images and convert them into electrical impulses, which reach the brain through the optic nerve.

If the retina is affected, vision can be compromised to the same extent. Although most patients with this condition do not show symptoms until the disorder is advanced.

Depending on the evolution, time and severity of the hypertensive retinopathy, the symptoms may vary. Among them are the following:

  • Headache, mild to moderate.
  • Blurry vision: it can be temporary and reset.
  • Significant loss of vision: particularly when the patient suffers from diabetes mellitus or concomitant atherosclerosis.
  • Vessel dilatations (aneurysms).
  • Scattered subconjunctival hemorrhages: by bursting of blood vessels in the sclera.
  • Optic disc edema or inflammation in the optic nerve.
The retina is a fine tissue that has the ability to capture light signals and transmit them to the brain.

Types and grades

In hypertensive retinopathy, the severity is determined according to the symptoms present, based on the Keith-Wagener-Barker classification system. It establishes a scale that goes from grade 1 to 4, the latter being the most serious:

  • Grade 1: There may be no noticeable symptoms, the narrowing of the arteries being very mild.
  • Grade 2: detectable narrowing. Visual irregularities may be experienced and there are more constrictions of the retinal artery.
  • 3rd grade: swelling in parts of the retina. There are also edema, microaneurysms, cotton wool spots, and hemorrhages.
  • Grade 4: inflammation of the optic nerve with macular edema. Severe vision problems and risk of having a stroke.

On the other hand, it is considered that there may be acute and chronic hypertensive retinopathy. The first is the most common way. It is associated with high blood pressure.

The sharp variety, also called malignant or accelerated, it can appear abruptly, in a short time, accompanying a very marked increase in pressure. It is linked to pre-eclampsia and adrenal gland tumors.

Causes and risk factors

Prolonged and high blood pressure is the main cause of hypertensive retinopathy. Hypertension is considered when systolic values ​​are equal to or greater than 140 millimeters of mercury (mm Hg) and diastolic values ​​are 90 mmHg.

To a good extent, the risk factors for hypertensive retinopathy are the same as for high blood pressure, although there may also be others. These include the following:

  • Not keeping blood pressure under control.
  • Having associated diseases, such as atherosclerosis or hypercholesterolemia.
  • Obesity.
  • Smoking
  • Alcoholism.
  • High consumption of salt.
  • Stress.
  • Age over 50 years.
  • Personal or family history of hypertension.

According to some research, it is more common in people of African descent.

Diagnosis of hypertensive retinopathy

It is very important for people with high blood pressure to have regular eye exams to diagnose hypertensive retinopathy. For these purposes, various types of examinations are carried out.

First, the pupil is dilated using drops that make it enlarge. The most commonly used drugs for these purposes are atropine, as well as phenylephrine, tropicamide, and cyclopentolate.

Once this is done, the doctor will use an ophthalmoscope, which is a tool that projects light to illuminate the pupil, allowing the retina and the back of the eye to be examined. This is a painless procedure that takes less than 10 minutes.

In certain cases a test known as fluorescein angiography. A dye (fluorescein) is injected into the veins, taking pictures of the eye to see what the blood flow is like in the retina. Also, other tests, such as optical coherence tomography (OCT), may be required.

Treatment of hypertensive retinopathy

For the treatment of hypertensive retinopathy, the fundamental aspect is the control of arterial hypertension. This is accomplished through the use of medications and lifestyle changes.

In this sense, the doctor may recommend beta-blockers and ACE inhibitors; or others such as diuretics, calcium channel blockers, and renin inhibitors.

On the other hand, some of the complications of hypertensive retinopathy can be treated with injectable medications in the eye. And eventually with procedures that involve the use of lasers or surgery.

Regarding lifestyle changes, a diet rich in fruits and vegetables, lower fat intake, reduction of salt is recommended, little or no caffeine, as well as limitation in alcoholic beverages. Measures include quitting if you're a smoker, keeping your weight under control, and exercising regularly.

The retinal exams are not many and in a short time they allow to have an accurate diagnosis.

Consequences and complications

The retina will recover if blood pressure can be kept under control. And although the prognosis is positive in grades 1 and 2 of the scale, at a higher level there may be permanent damage to the optic nerve or the macula.

As main complications of hypertensive retinopathy, we mention the following:

  • Superficial hemorrhages in the retina.
  • White areas that lack oxygen (cotton stains).
  • Hard exudates, due to the deposit of intraretinal lipids.
  • Inflammation of the optic disc.
  • Retinal artery or retinal vein occlusion.
  • Ischemic optic neuropathy, with loss of vision.
  • Hypertensive choroidopathy.
  • Papilledema.

Additionally, higher grades of hypertensive retinopathy are also associated with a higher likelihood of stroke occurrence, according to studies. Likewise, in another investigation, a increased risk of heart attack, heart failure, and death in people with high blood pressure.

Can hypertensive retinopathy be prevented?

Hypertensive retinopathy is a consequence of another problem, which is high blood pressure. The good news is that high blood pressure is a modifiable risk factor. This means that it can be kept in check.

People with high blood pressure rarely notice symptoms. Most feel nothing.

The condition will not be known to exist until it has progressed a lot. This means that you have to be more proactive. If you suffer from high blood pressure, you have to regularly go to the ophthalmologist and request a complete examination.

And if you have suddenly begun to experience changes in vision, all the more reason you should go to the doctor promptly. If the disease is in the early stages, the damage to the retina may be reversible.