Systemic Hypertension in Cats
Hypertension, more commonly referred to as high blood pressure, occurs when the cat's arterial blood pressure is continually higher than normal. When it is caused by another disease, it is called secondary hypertension; primary hypertension, meanwhile, refers to when it actually is the disease. Hypertension may affect many of the cat's body systems, including heart, kidneys, eyes, and the nervous system.

Symptoms and Types
The following are just some of the more common symptoms displayed by cats with high blood pressure:

• Seizures
• Circling
• Disorientation
• Blindness
• Dilated pupils
• Retinal detachment
• Hemorrhage of the eye
• Blood in the urine
• Protein in the urine
• Bleeding from the nose
• Swollen or shrunken kidneys
• Heart murmurs
• Weakness, either on one side of the body or in the legs
• Involuntary oscillation (rolling) of the eyeballs
• Palpable thyroid gland (when hyperthyroid)

Causes
The cause of primary hypertension in cats is not known. However, it may have a genetic component. So how prevalent is this form of hypertension? Studies have varied, but one study found that 65 percent of cats with chronic renal failure and 87 percent of cats with hyperthyroidism had mild high blood pressure. Ages of cats with hypertension ranged 4 to 20 years old.

Secondary hypertension, which accounts for 80 percent of all hypertension cases, may be due to a variety of factors, including renal disease, hormonal fluctuation, and hyperthyroidism.

Diabetes may also be a cause for hypertension, although it is uncommon in cats. If you suspect that your cat is suffering from hypertension, bring it in so that your veterinarian may provide a proper diagnosis.

Diagnosis
Blood pressure is often measured in pets in the same manner as in humans. An inflatable cuff will be placed on the cat's paw or tail, and standard blood pressure measuring instruments will check the pressure. It is important to keep the cat still long enough to get an accurate reading.

The standards for cat blood pressure are:

• 150/95 – at this reading or below, there is minimal risk and treatment is not recommended
• 150/99 to 159/95 -- intervention is rotuinely not recommended at these readings
• 160/119 to 179/100 -- treatment should be sought to limit the risk of organ damage
• 180/120 -- immediate treatment should be sought to limit the degree of other more severe complications

Five to seven measurements are generally taken. The first measurement will be discarded, and the cat's excitement level during the procedure will be taken in account. If the results are in dispute, the procedure will need to be repeated.

Treatment
The underlying cause of the high blood pressure will be treated first. Otherwise, the cat will probably be on medication to control the blood pressure indefinitely. The medication of choice is either a calcium channel blocker or a beta-blocker. As to cat's diet, the veterinarian may recommend food that are lower in sodium.

Blood pressure should be checked regularly, and some lab tests may be ordered by your veterinarian to measure your cat’s reactions to the medication.

Foundation For Feline Renal Research, the only 501(c)(3) nonprofit foundation dedicated exclusively to the understanding and treatment of feline kidney disease, is pleased to announce a $20,000.00 grant to the Royal Veterinary College, London, in support of their groundbreaking study "Unravelling The Genetic Basis for Blood Pressure and Kidney Function In the Cat". This important work, which is starting now, will be led by Dr. Rosanne Jepson, BVSc (Dist) MVetMed PhD DipACVIM DipECVIM MRCVS and Dr. Jonathan Elliott, MA, Vet MB, PhD, Cert SAC, Dip ECVPT, MRCVS.

Kidney disease is one of the biggest killers of companion cats; it causes great pain and suffering, and there is no cure. As many as one in three cats will ultimately develop the disease. The goal of this study is to isolate and analyze genes that influence renal disease and hypertension (the two diseases often go hand in hand).

According to Dr. Jepson, "Kidney disease is one of the most common conditions that we see in ageing cats. Some of these cats also develop high blood pressure (hypertension) which can result in damage, particularly to their eyes, and can lead to blindness. We know that, in human medicine, there are genes that are involved in both kidney disease and hypertension. At the Royal Veterinary College we have been studying these conditions for over 20 years. Thanks to the funding provided by Foundation For Feline Renal Research, we are now in a position to use newly developed cutting edge technology to look for gene associations in almost 1000 cats. As far as we know, this will be the first and largest study looking at genes associated with kidney disease and blood pressure in older cats. It's really exciting to be starting new work that we hope will expand our knowledge of both of these important conditions."

This humane study utilizes DNA from blood samples obtained for diagnostic purposes from companion cats during the course of their regularly scheduled veterinary visits. The samples, after being used for the necessary diagnostic purposes, were preserved for use in this study with the consent of the cats' human companions.