High blood pressure in cats

High blood pressure in cats is usually caused by an underlying disease, but it may occur on its own. It can cause serious damage to organs that are sensitive to elevated blood pressure, including the eyes, kidneys, heart, and brain. Older cats are more likely to suffer from this condition.

High blood pressure or systemic hypertension, occurs when your cat’s blood pressure is continuously higher than normal. Because symptoms of high blood pressure are sometimes hard to notice, routine health checks with your vet are important to detect early problems.

Overview

What is high blood pressure in cats?

Blood pressure refers to the pressure if the blood against the artery walls, it’s measured in millimetres of mercury (mmHg).

A cat with a constant blood pressure of 140mmHg or above 160mmHg is considered to have high blood pressure.

The most common causes of high blood pressure in cats are:

Kidney disease
Endocrine disorders: hyperthyroidism, diabetes, primary hyperaldosteronism, hyperadrenocorticism and adrenal gland tumour called pheochromocytoma.

Symptoms

Symptoms of high blood pressure in cats

Some cats with high blood pressure may not show obvious signs.

If hypertension is associated with an underlying disease, you may notice some or all of the following in your cat:

Lethargy or weakness
Reduced appetite
Losing weight
Increased drinking
Increased urination
Sudden blindness
Blood inside the eye
Seizures
Head tilt
Tripping while walking

Risk

Are some cats more at risk of high blood pressure than others?

Older cats, usually more than 10 years old, are more prone to this problem. The diseases that cause high blood pressure are also more likely to occur in this age group.

Cats who have been diagnosed with chronic kidney disease, hyperthyroidism and hyperaldosteronism are therefore at higher risk.

Diagnosis

How is high blood pressure diagnosed?

Your vet will take into account all your cat’s clinical signs and perform a blood pressure test.

Blood pressure test: The blood pressure is measured using a cuff that is placed around a leg or tail and attached to a measuring device.

Getting an accurate blood pressure reading in cats can be difficult. Pets can experience temporary elevations in blood pressure due to the stress of being at the vet practice. This may lead to several visits being needed for blood pressure measurement before the diagnosis of high blood pressure can be confirmed.

Once hypertension is confirmed, your vet may recommend the following tests to determine if other problems are present:

Eye examination: Your vet will look specifically for signs of blindness, blood inside the eye, and damage to the retina.
Blood test: Usually includes routine complete blood count and biochemistry profile, but can also include specific tests to look into kidney and thyroid function.
Urine test
Radiographs: Abdominal and/or chest x-rays.
Ultrasound scan: To assess the shape and structure of the abdominal organs.

Vet treatment

What is the treatment for high blood pressure in cats?

Your vet may recommend one or more of the following, based on your cat’s specific needs:

Medications used to lower blood pressure (such as enalapril or benazepril, amlodipine or telmisartan)
Treatment of any underlying conditions
Treatment of any side effects of hypertension, such as eye and heart disease

Home treatment

How can you help your cat with high blood pressure?

Minimise stress: offer hiding spots and avoid loud noises.
Avoid high salt intake, such as human food and certain treats. Unlike in humans, salt restriction is often not necessary. Talk to a vet about possible dietary recommendations depending on your cat’s underlying condition.
Train your cat to have their blood pressure taken. This can be done at home. Ask your vet to borrow a cuff or purchase one yourself.

Prevention

How to prevent high blood pressure in cats

About 13-20% of cats have hypertension without an underlying cause (primary hypertension). However, a portion of these cats may be in the very early stages of an underlying disease, such as chronic kidney disease, but routine blood tests can’t yet detect it.

Keep up to date with annual health checks with your vet. As your cat ages, consider including routine blood and urine tests, and possibly blood pressure measurement.
Keep your cat at a healthy weight. Talk to a vet nurse if you need help with helping your cat lose weight.

When to worry