Diets for Managing CKD in Cats

Posted on October 1, 2023 by felinepurrspective_u3q4o6

Diet is a key therapy for cats with chronic kidney disease (CKD). Diets for managing CKD in cats aim to (Reference 1):

lessen the clinical signs of CKD
slow the progression of the disease
provide adequate nutrition

Diets for managing ckd in cats

The goal of diets for managing CKD in cats is to reduce the amount of uremic waste products while providing adequate nutrition. There are a number of commercially available diets that are formulated to do this. These foods feature (Reference 1):

reduced phosphorus
restricted amounts of high-quality protein
higher calories
reduced sodium
potassium supplementation
B vitamins and fatty acids

Phosphorus

Phosphorus is needed for the growth, maintenance, and repair of all tissues and cells, and for the production of the genetic building blocks, DNA and RNA. Phosphorus is also needed to help balance and use other vitamins and minerals, including vitamin D, iodine, magnesium, and zinc (Reference 2).

As kidney disease progresses, the ability of the kidneys to excrete phosphorus declines. To reduce stress on the kidneys, diets for managing CKD in cats aim to reduce the amount of phosphorus and balance the ratio of calcium to phosphorus. Too much phosphorus and not enough calcium can lead to kidney and bone damage (Reference 1). Commercial kidney diets are formulated to maintain an appropriate ratio of calcium to phosphorus.

protein in diets for managing cats with ckd

Since protein contributes significantly to phosphorus content, kidney diets restrict the amount of protein. Less protein means less uremic waste products. Emphasis is placed on formulating these diets with “high quality” protein. High quality proteins are a “complete package” and provide the cat with all the amino acids he or she needs. Thus, the protein used is highly bioavailable and generates less uremic waste products (Reference 1).

There are concerns that reduced protein diets predispose cats to weight loss and loss of lean muscle mass. Some recent studies suggest that senior cats may require more protein than younger cats to maintain lean body mass (LBM) (Reference 1).

Some practitioners advocate feeding higher protein diets to cats suffering with CKD to maintain the LBM. This may not be the answer to maintain LBM – increased protein in the cat’s diet means more uremic waste, making the cat feel nauseated and not inclined to eat. Ultimately, the cat will be eating less and calorie reduction will lead to muscle wasting as the cat’s body uses his own muscles for nutrition (Reference 3).

More on Lean Body Mass…

A recent study in 2019 (Reference 4) found a correlation between consumption of essential amino acids (essential amino acids must be consumed in the diet) and LBM. Cats with CKD Stages 1 and 2 were fed either a control kidney diet or a higher calorie “test” kidney diet that included higher amounts of essential amino acids and carnitine, an amino acid derivative that plays a role in energy production in the body.

The cats eating the lower calorie control diet lost LBM whereas the other group of cats eating the “test” diet maintained their LBM. Researchers observed that the cats on the control diet did not eat enough food to get adequate amounts of essential amino acids. They found that essential amino acid intake, not total dietary protein, correlated with maintaining LBM.

Although offering reduced protein, most commercial kidney diets make sure that more than sufficient amounts of the essential amino acids are available. The challenge is to get cats with CKD to eat enough of the diets.

Other Supplements

Commercial diets for managing CKD in cats also supplement:

Potassium, an electrolyte essential to the function of muscles and nerves
B vitamins – these water soluble vitamins can be depleted as the cat drinks more water and urinates more
Fatty acids – fatty acids found in fish oils are thought to reduce inflammation and decrease protein in the urine

Starting a kidney Diet

Renal diets are typically recommended for cats in IRIS Stages 2, 3, and 4. Occasionally a reduced protein diet may be prescribed for a Stage 1 cat who has persistent protein in her urine. Many practitioners like to introduce therapeutic diets when the cat is in IRIS Stage 2, because the cat should still be feeling well and more likely to accept the new diet (Reference 3).

The best time to switch to a kidney diet is when your cat is eating her regular cat food well and is feeling well. Wait to introduce the new diet if…

Your cat has just come back from the hospital
You have visitors or are doing home remodeling
Your cat is not eating her regular food well
Your cat is vomiting or having diarrhea

Introduce the new diet gradually, over several weeks (Reference 1)


Week 1	Week 2	Week 3	Week 4
Offer 25% of the new diet and 75% of the current food	Offer 50% of the new diet and 50% of the current food	Offer 75% of new diet and 25% of the current food	Offer 100% of the new diet

Make sure to offer the appropriate amount of calories to your cat – the new renal diet will most likely be more caloric than the your cat’s current food and you will not need to feed as much.

tips for transitioning to a kidney diet

Choose a food similar to the one your cat is eating already – wet or dry? fish or chicken?
Offer the new food in a separate bowl alongside the regular food
Make sure to offer fresh food
Use a “topper” to encourage your cat to try the new food – fish flakes or a favorite treat
Try gently warming wet foods – the stronger smell may make the food more appealing
Meal feed your cat – small, frequent meals gives your cat more chances to try the new food
Avoid mixing medications into the new food – use a small amount of another food or pureed treat to give the medications

If you are struggling with a finicky cat, talk to your vet. If your cat is healthy, ask if you can do a trial of mirataz to stimulate his appetite and facilitate the transition to the new food.

Alternatives to a commercial kidney diet

Use a phosphorus binder in the food your cat will eat. Consult your veterinarian for the appropriate dose.
Home cooked diets are an option but should be formulated by a veterinary nutritionist. Nutritionists affiliated with websites such as balance.it will work with your vet to formulate a recipe for your cat.

Studies have shown that diets for managing CKD in cats can increase longevity, help control uremia and maintain phosphorus concentrations. While some have concerns about the protein restriction in these diets, kidney diets have been shown to maintain LBM providing the cat eats enough food to get sufficient nutrition.

New research is focusing on the connection between the kidneys and the GI tract, particularly the uremic toxins that originate in the gut. Prebiotic and probiotic treatments in CKD cats are being investigated to see if improving the health of the microorganisms living in the gut can reduce blood concentrations of gut-derived uremic toxins. (Reference 5)

references

Quimby, J. and Ross, S., Diets for Cats with Chronic Kidney Disease (CKD) [updated 2022]. http://www.iris-kidney.com/education/protein_restriction_feline_ckd.html [viewed 9/2023]
Phosphorus: Fact Sheet for Health Professionals, https://ods.od.nih.gov/factsheets/Phosphorus-HealthProfessional/, viewed 9/2023.
Cave, N. and Wall, M. Protein restriction for cats with chronic kidney disease, Vet Focus, Issue # 30.1, © 6/25/20
Hall JA, Fritsch DA, Jewell DE, Burris PA, Gross KL. Cats with IRIS stage 1 and 2 chronic kidney disease maintain body weight and lean muscle mass when fed food having increased caloric density, and enhanced concentrations of carnitine and essential amino acids. Vet Rec. 2019 Feb 9;184(6):190. doi: 10.1136/vr.104865. Epub 2018 Dec 4. PMID: 30514741; PMCID: PMC6589452.
Summers, S. and Quimby, J., The feline gut-kidney axis: food for thought, Veterinary Focus, Issue #33.1, 5/31/23, https://vetfocus.royalcanin.com/en/scientific/the-feline-gut-kidney-axis-food-for-thought, viewed 9/2023

Managing the Cat with Chronic Kidney Disease

Posted on September 24, 2023 by felinepurrspective_u3q4o6

HDO BP cat — A cat relaxes in his basket during a home blood pressure check. Regular blood pressure checks are essential to monitoring chronic kidney disease.

Chronic Kidney Disease (CKD) in cats is progressive and not curable but there are strategies we can undertake to improve the quality of life of our “kidney” cats and possibly give them some more time with us. Here is a checklist for managing the cat with chronic kidney disease:

Keep Kitty hydrated
Feed a diet that will lessen the stress on the kidneys
Maintain appetite
Manage high blood pressure
Treat anemia if necessary
Treat urinary tract infections

Managing the cat with chronic kidney disease

hydration

Kidney failure is tied to the “death” of nephrons that filter the blood. The remaining nephrons compensate by increasing filtration. Dehydration decreases renal blood flow putting more stress on the remaining nephrons. Keeping the “kidney” cat hydrated helps maintain electrolyte concentrations and dilute the waste products the kidneys are struggling to filter out.

Increasing Voluntary Water Intake

Have a variety of water sources and fountains in the home to encourage water intake.
Consider feeding a wet diet – many canned foods contain about 80% water.
Try water from tuna, water used to poach chicken or fish (offer alone, add to the water bowl, or try frozen in an ice cube tray and added to the water bowl).

Hydration supplements like Purina’s Hydra Care are designed to maximize the amount of water cats take in while drinking. Nutrient enriched water is more viscous, clings to the cat’s barbed tongue, and increases the water consumed with each lap of the tongue.

Subcutaneous Fluids

This refers to giving fluids under the skin, not in a vein. It is done using a bag of sterile fluids, an IV line and a needle. This is a strategy often employed in IRIS stages 3 and 4 of kidney disease. This can be done in the veterinary clinic or at home, once you and your cat are comfortable with the process.

Kidney-friendly diets

As the kidneys fail, they are no longer as efficient at filtering the waste products of protein metabolism. Phosphorus in the form of phosphates tends to build up in the body while potassium levels may drop.

Commercial renal diets for kidney cats feature reduced phosphorus and restricted amounts of high-quality protein, an increased calorie density, sodium restriction, potassium supplementation, supplementation with B vitamins, anti oxidants and omega-3 fatty acids (Reference 1). There have been a number of studies done addressing the effectiveness of these diets – the results show that cats suffering from CKD lived longer when fed a renal diet (Reference 2).

Phosphorus Binders

For some cats in advanced stages of CKD, a renal diet may not reduce phosphorus enough; other cats simply refuse to consume a renal diet. For these cats, adding a “binding agent” to the food can help reduce the amount of phosphorus that is available for the cat to metabolize. Supplements that “bind” with the phosphates in the food form a nonabsorbable compound eliminated in the stool. “Phosphorus binders” include (Reference 1):

Aluminum hydroxide
Calcium carbonate
Calcium acetate
Sevalamer (a hydrogel of poly-allylamine, free of aluminum and calcium)

appetite and nausea

A “kidney” cat can suffer from nausea and vomiting due to the buildup of uremic toxins in the bloodstream. The cat consequently doesn’t eat well resulting in dehydration and weight loss. Reduced potassium levels and anemia due to CKD also contribute to a reduced appetite (Reference 1).

Medical Management

Managing the cat with chronic kidney disease also includes managing nausea and vomiting. Drugs that target nausea and vomiting include maropitant (Cerenia) and ondansetron. These are typically available in oral tablets.

There is another drug that is often the first choice of many practitioners. Mirtazapine is an antidepressant drug that not only controls nausea and vomiting, it also stimulates appetite.

available in a transdermal gel (Mirataz) as well as tablets
the transdermal form is FDA approved for use in cats
the transdermal gel is applied once daily and the dose is easily adjusted
side effects are vocalizing and increased activity.

If a cat is too nauseous or unwell to maintain food intake, a feeding tube should be considered.

high blood pressure

Increased filtration rate in the remaining nephrons and activation of the renin-angiotensin system can lead to high blood pressure in cats with CKD. Systolic blood pressures over 160 mm Hg require treatment to prevent damage to the cat’s eyes, heart and kidneys. In particular, the leakage of proteins into the urine (proteinuria) can be reduced once high blood pressure is managed (Reference 1).

Amlodipine is the most commonly used drug to reduce cats’ blood pressure. It is a calcium channel blocker that is available in tablets that can be taken once or twice daily. Amlodipine typically reaches therapeutic levels in 7-10 days. Managing the cat with chronic kidney disease should include a blood pressure check every 3-6 months.

anemia

One of the kidney’s functions is to produce the hormone erythropoietin. Erythropoietin triggers cells in the bone marrow to make more red blood cells. Failing kidneys may not generate enough erythropoietin and anemia (low levels of red blood cells) can result.

Fewer red blood cells means less hemoglobin. Less hemoglobin means less oxygen is getting moved around the body. Anemia can result in weakness and tiredness.

If the fraction of red blood cells in the blood drops below 20%, many practitioners will supplement the cat with a man-made analog of erythropoietin. The most commonly used drug is darbepoetin; it is given as an injection under the skin. Injections of iron supplements often accompany the darbepoetin injections in the initial stages of therapy (Reference 1).

A new treatment (2023) is available for anemia in cats with CKD. Varenzin -CA1 is a once daily oral liquid medication made specifically for cats. Varenzin-CA1 is designed to stimulate the cat’s body to make its own erythropoetin.

Urinary tract infections (UTI)

With increasingly dilute urine seen in cats with CKD, UTI’s are more common. Most of these UTI’s do not have clinical signs such as frequent urination or blood in the urine. Urinalysis should be part of the CKD cat’s checkup. White blood cells found in a centrifuged urine sample are indications for a bacterial culture and treatment. Treatment can be based on sensitivity testing and a kidney friendly antibiotic chosen.

Managing the cat with chronic kidney disease requires attention to multiple factors. Treating dehydration, nausea, high blood pressure and anemia can keep the “kidney” cat comfortable and slow the progression of the disease. A critical part of managing the cat with chronic kidney disease is feeding an appropriate diet. The next post will look at the science behind the commercial renal diets and alternatives to them.

references

Sparkes, A. (panel chair), ISFM Consensus Guidelines on the Diagnosis and Management of Feline Chronic Kidney Disease, Journal of Feline Medicine and Surgery (2016) 18, 219–239.
Quimby, J. and Ross, S., Diets for Cats with Chronic Kidney Disease (CKD) [updated 2022]. http://www.iris-kidney.com/education/protein_restriction_feline_ckd.html [viewed 9/2023]

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Chronic Kidney Disease in Cats

Posted on September 17, 2023September 17, 2023 by felinepurrspective_u3q4o6

Cat on Baby Scale — Weight loss is a symptom of kidney disease.

Chronic kidney disease (CKD) is common in older cats. A 2014 study found that 30-40% of cats over age 10 years had CKD. (Reference 1).

chronic kidney disease in cats

Let’s take a closer look at what the kidneys do for our cats.

regulate fluid volume in the body
maintain the pH and electrolyte composition of the body.
make renin, an enzyme that helps maintain blood pressure
make erythropoietin, a hormone that stimulates production of red blood cells
filter the blood removing waste products

Nephrons are the tubular structures in the kidney that filter the blood and produce urine. A cat’s kidney has about 200,000 nephrons (Reference 2).

Over time, nephrons become damaged and are replaced by scar tissue. Renal failure occurs when less than 25% of the nephrons are functional and the remaining nephrons can’t maintain adequate function. The most common cause is an inflammatory process called tubulointerstital nephritis (Reference 3).

The remaining nephrons compensate by increasing filtration rate. The result of this “hyper filtration” is scarring of the tubes in the nephrons and loss of protein into the urine. The “hyperactive” nephrons also release the enzyme renin. Renin triggers the production of the hormone, angiotensin II, that makes heart beat more forcefully and raises the cat’s blood pressure. (Reference 3).

Diagnosing Chronic Kidney Disease in Cats

Clinical Signs of Chronic Kidney Disease

Some clinical signs are similar to those of other chronic diseases such as hyperthyroidism and diabetes. Like those disorders, these signs are usually not present until later in the disease process.

weight loss
increased thirst and urination
rapid pulse and breathing
unkempt hair coat

In addition the “kidney cat” may have

lethargy
weakness
poor appetite
bad breath or ulcers in the mouth (occasionally)

Diagnosing Chronic Kidney Disease in Cats

CKD is typically diagnosed by measuring creatinine and SDMA in the blood and measuring the urine concentration (Reference 1).

Creatinine

Creatinine is a by-product of energy-producing processes in the muscles. A healthy cat’s kidneys filter out most of the creatinine. As kidney disease progresses, the remaining nephrons filter out less creatinine and values of creatinine in the blood rise.

SDMA

SDMA (symmetric dimethylarginine) is a metabolite of arginine, one of the essential amino acids for cats. SDMA is produced from metabolism of proteins and, like creatinine, is filtered out by the kidneys. Unlike creatinine, SDMA is not influenced by the change in muscle mass. SDMA is more sensitive to the increase in the filtration rate as kidney disease progresses. It will increase earlier than creatinine.

Urine Concentration

As remaining nephrons increase filtration to compensate for the loss of nephrons, the cat drinks more fluid and the urine he produces becomes more dilute. As CKD progresses, urine concentration decreases.

the stages of chronic kidney disease

The International Renal Interest Society (IRIS) has formulated a guide to staging CKD in cats, as well as in other animals. There are 4 stages of CKD. The table below summarizes the values for creatine and SDMA seen for cats in the stages of CKD.

Stage	Creatinine (mg/dL)	SDMA (mcg/dL)	Comments
Stage 1	<1.6	<18	Blood values are normal but urine is dilute or kidneys are abnormal on examination or imaging
Stage 2	1.6 – 2.8	18 – 25	Clinical signs are mild or absent
Stage 3	2.9 – 5.0	26 – 38	Clinical signs are present but vary in severity
Stage 4	>5.0	>38	Risk of uremic crisis

Signs of Uremic crisis (end stage kidney failure):

Refusal to eat, vomiting, lethargy, confusion (possibly pacing and restlessness), withdrawn, uncontrolled urination or defecation, ammonia-like odor to the breath, seizures (from https://www.petmd.com/cat/conditions/urinary/kidney-failure-cats). Emergency treatment is needed.

other signs of chronic kidney disease in cats

Even if creatinine and SDMA are within normal limits, high blood pressure and protein in the urine may indicate that a cat has kidney disease. Recall that as nephrons “die”, the remaining nephrons increase filtration to compensate and blood pressure rises. The higher pressure damages the walls of the tubes in the nephrons and protein can leak out into the urine.

High Blood Pressure

Systolic blood pressures under 140 mm Hg are considered normal; SBP 140- 159 is prehypertensive; over 160 is hypertensive and treatment is recommended. (see “Measuring Your Cat’s Blood Pressure: Why and How”)

Protein in the Urine

Protein in the urine can be associated with disease processes such as urinary tract infection. Persistent protein in the urine warrants a closer look and the veterinarian will often choose to run a test to measure the urine protein creatinine ratio (UPCR). UPCR < 0.2 are normal; ratios of 0.2-0.4 are borderline; ratios over 0.4 support a diagnosis of CKD.

Diagnosis of chronic kidney disease can be challenging. Clinical signs are non specific and shared by other chronic diseases such as hyperthyroidism and diabetes. Because the kidneys have so much reserve capacity and our markers do not detect it until nephron death approaches 70-80%, it can be easy to miss some of the more subtle indicators of kidney dysfunction. It is important for our cats to have regular exams to assess their overall condition, lab work, and blood pressure measurement. Kidney disease is progressive and not curable, however, early intervention can slow down the process. In the next post, we discuss treatment of Stage 1 through Stage 4 of chronic kidney disease in cats.

references

Sparkes, A. et al. ISFM Consensus Guidelines on the Diagnosis and Management of Feline Chronic Kidney Disease, Journal of Feline Medicine and Surgery (2016) 18, 219–239, https://journals.sagepub.com/doi/pdf/10.1177/1098612×16631234
Sadeghinezhad, J. and Nyegaard, J. Cat Kidney Glomeruli and Tubules Evaluated by Design-Based Stereology. The Anatomical Record, Volume 302, Issue 10, 18-46-1854, 14 May 2019, https://doi.org/10.1002/ar.24144
Grauer, Gregory, Feline Chronic Kidney Disease, Today’s Veterinary Practice, February 6, 2015, Issue March/April 2015, https://todaysveterinarypractice.com/urology-renal-medicine/feline-chronic-kidney-disease/

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Diagnosing and Treating Hyperthyroidism in Cats

Posted on September 10, 2023September 10, 2023 by felinepurrspective_u3q4o6

Over 10% of cats over 8 years old will be diagnosed with hyperthyroidism in their lives. Although evidence points to thyroid disrupting chemicals in the cats’ food and environment, we don’t really know why these cats will become hyperthyroid. Prompt diagnosis and treatment will help these cats live long and healthy lives.

Diagnosing and Treating Hyperthyroidism in Cats

Diagnosing

Clinical signs of hyperthyroidism include increased appetite and weight loss. These signs progress slowly and it may be months to years before the cat owner realizes that something is wrong.

Cats are considered seniors at the age of seven. Regular lab work is recommended for senior cats and most senior feline blood panels include a thyroid hormone (T4) measurement. Persistently elevated T4 concentrations coupled with one or more of the classic clinical signs (below) at the same time often confirms the diagnosis of hyperthyroidism. (Reference 1)

weight loss
increased thirst and urination
increased vocalization
hyperactivity
rapid pulse and breathing
vomiting, diarrhea
unkempt hair coat

This list of clinical signs is also shared with other feline diseases, such as diabetes, kidney disease, and GI disorders. These diseases can lower the T4 measurement, so that it is in the reference range, making diagnosis of hyperthyroidism challenging.

a challenging diagnosis

Cats that may have kidney disease as well as hyperthyroidism are particularly challenging to diagnose. Thyroid hormone increases the blood flow through the kidneys, often lowering kidney values to within the reference ranges. At the same time, kidney disease impairs the binding of T4 to proteins, reducing the T4 concentration. One disease masks the other and vice versa (Reference 2).

Cats with borderline T4 values and those suspected of having another chronic disease will need additional testing before a definitive diagnosis of hyperthyroidism is made. The veterinarian may request a more sensitive test called a “free T4 by equilibrium dialysis” in addition to remeasuring total T4. “Free T4” measures a form of T4 that is not bound to proteins in the blood. (Reference 3)

Routine thyroid monitoring in humans and dogs measures levels of TSH or thyroid stimulating hormone. Unfortunately, levels of TSH in hyperthyroid cats are often too low to be detected using canine tests. Zomedica has recently developed a feline TSH assay capable of measuring the low levels of TSH in cats which may aid in diagnosing feline hyperthyroidism. (Reference 3)

treating hyperthyroidism in cats

At the present time, there are 4 treatments available to cats with hyperthyroidism (Reference 1).

radioactive iodine (I-131)
medical management with a drug called methimazole
surgical removal of abnormal thyroid tissue
dietary therapy using iodine-restricted food

1. Radioactive Iodine (I-131)

Treating hyperthyroidism in cats with radiation must be done at a licensed facility. An injection of radioactive iodine is given under the skin, like a vaccine. The cat stays at the facility until radiation levels drop enough to send cat home (about 3-4 days) (Reference 1, 4)

95% cure rate
side effects are rare
small risk of hypothyroidism (too much tissue is destroyed and the cat will need thyroid supplements)
owner must store wastes and soiled litter for 2 weeks
cannot cuddle kitty for extended times for 2 weeks post discharge (e.g. cat cannot sleep on bed)

2. Medical Management with Methimazole (Reference 1)

not a cure and the cat must receive daily medication to manage his hyperthyroidism
methimazole is available in pills and transdermal gel
frequent monitoring of T4 values is necessary
side effects: vomiting, facial itching, liver failure
tumor may continue to grow and become cancerous

3. Surgical Removal of Thyroid Gland (Reference 1)

The abnormal thyroid tissue is removed surgically, leaving the normal tissue alone. It is a procedure most surgeons can perform.

up to 90% cure rate
if not all the abnormal tissue is removed, hyperthyroidism can return
general anesthesia can be risky in cats with cardiac issues and kidney disease
there is a risk of damaging the adjacent parathyroid glands (regulate calcium in the body)
risk of hypothyroidism if too much normal tissue is removed

4. Dietary therapy (Reference 1)

Hills y/d diet reduces the amount of thyroid hormone in the body by decreasing the amount of iodine in the cat’s food.

response is 82% when on the diet
safe for cats with kidney disease
the cat cannot eat other foods
only low-iodine treats and water can be used
the cat will become hyperthyroid if he stops eating the diet

Both I-131 and thyroid surgery offer a cure for hyperthyroidism. However, both have a low risk of too much normal tissue being destroyed and the cat developing “hypothyroidism” as a consequence. The “hypothyroid” cat does not produce enough thyroid hormone and must be supplemented with daily oral medication for the rest of his/her life.

Both I-131 and surgery run the risk of unmasking more advanced kidney disease. Unlike medication or diet which can be adjusted or stopped, I-131 and surgery are permanent. Before recommending I-131 or surgery, some practitioners will conduct a trial with methimazole to assess kidney function when the hyperthyroidism is managed. However, some clinicians will opt to treat with I-131 even in the face of advanced kidney disease – persistent hyperthyroidism will further damage the kidneys if left untreated (Reference 5).

Diagnosing and treating hyperthyroidism in cats can be challenging. The presence of other diseases can mask hyperthyroidism and interfere with testing. I-131 is considered the gold standard for treating hyperthyroidism in cats. It does not carry the risks of surgery, avoids the side effects of methimazole and the difficulties of maintaining a strict prescription diet with a cat. Whichever treatment you choose, you have taken a step toward giving your hyperthyroid cat a healthier and longer life.

references

Carney HC, Ward CR, Bailey SJ, et al. 2016 AAFP Guidelines for the Management of Feline Hyperthyroidism. Journal of Feline Medicine and Surgery. 2016;18(5):400-416. doi:10.1177/1098612X16643252
Geddes R, Aguiar J. Feline Comorbidities: Balancing hyperthyroidism and concurrent chronic kidney disease. Journal of Feline Medicine and Surgery. 2022;24(7):641-650. doi:10.1177/1098612X221090390
Kvitko-White, Heather. Recognizing and confirming feline hyperthyroidism. dvm360 March 2021 Volume 53, Feb 9, 2021. https://www.dvm360.com/view/recognizing-and-confirming-feline-hyperthyroidism (viewed 9/2023)
Brooks, Wendy. Thyroid Treatment Using Radiotherapy for Cats. Veterinary Partner:VIN. Date Published: 01/01/2001
Date Reviewed/Revised: 09/05/2023. https://veterinarypartner.vin.com/default.aspx?pid=19239&id=4951399 (viewed 9/2023)
Vaughan, F. and Wackerbarth, D. “Methimazole Trials: What Are They Good For?”, https://www.felinehtc.com/documents/Methimazole-Trials.pdf (viewed 9/2023)

Hyperthyroidism in Cats – What is it? Why Does It Happen?

Posted on September 3, 2023 by felinepurrspective_u3q4o6

Thyroid Disruptors have a similar structure to the thyroid hormone T4

About 10% of senior cats will develop a condition called hyperthyroidism in their lives. Hyperthyroidism can affect a cat’s quality of life and potentially shorten it.

What is hyperthyroidism?
A cat has two thyroid glands, one on each side of the throat below the larynx or voice box. In a healthy cat, these glands are small and difficult to feel. In a cat with hyperthyroidism, these glands are enlarged due to an overgrowth of tissue. This tissue is functional and produces thyroid hormones. Chemical assay of an affected cat’s blood will show an excess of thyroxine (T4).

Most of these growths are benign – only 2% of hyperthyroid cats have cancerous tumors at the time of diagnosis (Reference 1).

Hyperthyroidism in Cats – what you may notice

Weight loss
Increase in vocalizing
Hyperactivity
Increased thirst and urination
Unthrifty haircoat
Vomiting
Diarrhea

Hyperthyroidism in cats – causes?

Hyperthyroidism was rare in cats prior to 1970 – the first case was officially reported in 1979 (Reference 2). What has changed since the ’70’s?

cats are living longer
more cats are eating commercial cat food
many cats live exclusively indoors

Longer Lifespan
Humans are more at risk to form small growths on their thyroid glands as they age (Reference 1). It is likely that older cats are also more predisposed to thyroid tumors.

Diet
Soy can be found in many cat foods, particularly dry formulations. Soy inhibits some of the key enzymes in the production of the thyroid hormones. The pituitary gland responds to the lower levels of thyroid hormones by producing TSH (thyroid stimulating hormone). More thyroid tissue grows to meet the need for thyroid hormones.

Studies with rats have linked eating soy with thyroid tumors, but only when consuming diets deficient in iodine (Reference 2). Could iodine supplementation help? More research is needed to determine how large a role iodine plays in feline hyperthyroidism. Most cats are exposed to other chemicals in their environment, drinking water, and diet that also affect thyroid function. How much do these chemicals contribute to the development of feline thyroid tumors?

Cat food can linings and Bisphenol A

Most canned cat foods have a plastic coating to extend the shelf life of the food inside and guard against contamination. Many of these canned linings contain a chemical called bisphenol A or BPA.

BPA has a chemical structure that is similar to the thyroid hormones and can possibly interfere with thyroid hormone function. (Even though most of the linings are PVC, BPA can be an additive in the processing of PVC). Although the FDA says the level of BPA in cans is very low and does not present health risks to humans, the agency did ban the use of BPA in baby bottles, sippy cups and infant formula packaging in July of 2012.

Hyperthyroidism in cats – the environment

Poly brominated diphenyl ethers (PBDE) are another class of compounds that have a chemical structure similar to the thyroid hormones and are known to disrupt thyroid metabolism. PBDE’s are used as flame retardants in electronics, furniture and textiles as well as construction materials (Reference 2).

In 2004, manufacturers in the US voluntarily stopped making many of the PDBE flame retardants. However, these chemicals accumulate in the environment and have been detected in significant amounts in animals as well as humans.

Multiple studies have found that house cats have serum levels of PBDE that are about 50 times higher than that in humans (Reference 2). A study at the University of Illinois found that feral cats had a lower level of PBDE’s in their blood than house cats. This indicates that house cats are exposed to PBDE in their homes.

Further work analyzed dust samples and found higher concentrations of PBDE’s in dust from the homes of hyperthyroid cats compared with those of healthy cats (Reference 2). As cats groom, they can ingest dust and possibly PBDE.

At this time, there are not any studies that have conclusively linked exposure to a specific chemical compound to hyperthyroidism in cats. Soy, iodine, BPA and PBDE’s may or may not play a significant role in cats becoming hyperthyroid (Reference 1).

Preventing Hyperthyroidism in cats

The suggestions below will certainly not hurt your cat and may limit his exposure to chemicals that can disrupt thyroid function (Reference 2).

Avoid cat food products containing soy products.
Limit fish-flavored foods: fish contain high levels of iodine and may be contaminated with PCB, PBDE, etc.
Feed wet foods in foil pouches in preference to using canned food possibly lined with coatings containing BPA
Home cooked diets can help help avoid contamination with chemicals but consult with a veterinary nutritionist so that the diet is balanced and complete.
Use ceramic or glass containers for feeding and storage to reduce exposure to chemicals like BPA.
Use filtered water from the tap to limit exposure to chemicals.
Vacuum regularly to limit the dust your cat ingests.
Avoid cat litters with deodorizers or odor neutralizers.

Thyroxine (T4) levels are routinely checked on most senior feline blood panels. Annual or bi-annual labwork will let you know if your cat is developing hyperthyroidism. This way, you can plan for appropriate treatment before your feline friend starts to show outward symptoms.

What are the treatment options for hyperthyroidism in cats? We will look at these in the next post.

references

Carney HC, Ward CR, Bailey SJ, et al. 2016 AAFP Guidelines for the Management of Feline Hyperthyroidism. Journal of Feline Medicine and Surgery. 2016;18(5):400-416. doi:10.1177/1098612X16643252
Peterson M. Hyperthyroidism in cats: what’s causing this epidemic of thyroid disease and can we prevent it? J Feline Med Surg. 2012 Nov;14(11):804-18. doi: 10.1177/1098612X12464462

Feeding the older, skinny cat

Posted on June 5, 2022June 5, 2022 by felinepurrspective_u3q4o6

Feeding the older, skinny cat can be a challenge. Older cats do not digest food as efficiently as younger ones and can require more calories. Due to disease and natural aging processes, the older cat often suffers from a reduced appetite. Reduced appetite means that less food is eaten. Less food eaten means the cat will lose weight and muscle mass.

Reduced appetite in the older, skinny cat can be due to:

Chronic kidney disease which can cause nausea
Pain due to dental disease or arthritis
Decreased odor and taste sensitivity (part of the aging process).

How can you get your older, skinny cat to eat better?

Offer a palatable food with the appropriate nutrients
Feed her in a way that mimics a cat’s natural behavior
Use appetite stimulants if necessary

palatable, nutritious food

“Senior” Diets

A recent study by researchers at Oregon State, Colorado State, and University of California, Davis found that the only difference between commercially available “senior”diets and the adult diets was that there was higher fiber in the senior diets. So find an adult food your cat likes – preferably one that has been evaluated in a feeding trial.

A therapeutic diet may be recommended by your veterinarian if your cat has kidney disease or another medical condition.

“Aging Cats Prefer Warm Food”

Ryan Eyre and colleagues investigated the effect of temperature on how much older cats eat. Thirty-two cats between 8 and 14 years of age participated in a “two bowl” study of a chunks and gravy food at different temperatures. The food was refrigerated or heated as needed to 43° F , 70 °F and 98 °F.

In a series of trials, each cat was presented with one bowl of colder food and a second bowl of warmer food. The amount of food consumed by the cats was recorded. The researchers also measured 1) thickness of the gravy at the different temperatures and 2) the volatile compounds released when the food was heated.

What they found:

There was no change in gravy thickness with temperature, so the texture of the food remained the same.
Heating increased the release of volatile compounds associated with a “meaty” flavor
Heating decreased the amount of volatile compounds that give rise to scents like orange peel

The cats preferred the warmer food in each of the pairs tested. They overwhelmingly preferred the food heated to 98 °F.

Other reasons cats may like warmed food:

The warmest food had a temperature similar to the prey a wild cat would eat – so maybe a little bit of instinct is at work here.
Heat is thought to activate taste receptors. Cats are thought to have about 470 taste buds and have taste receptors that detect salt, sour, bitter, and umami (meaty). So, heating food may also make it more palatable to cats by making it taste more “meaty”.

Heat your cat’s food before serving it – make sure to test before feeding. It should be “baby bottle” warm

Feeding your older, skinny cat: mimic natural feeding behavior

Feed small meals frequently
Use food puzzles to engage the cat in foraging behavior
Put food out in different locations
Consider elevated feeding stations for arthritic cats

Surefeeder for Cat — Athena’s Surefeeder opens only for her. Note the bubble on the back to keep the other cats out.

Reduce inter-cat stress in multi-cat households

Cats prefer to dine alone so have multiple feeding stations
Make sure that more dominant animals do not keep the older cat from eating
Investigate strategies to protect your older, skinny cat’s food – for example, consider a microchip feeder

medical intervention – appetite stimulants

Mirtazapine: Tetracyclic antidepressant that stimulates appetite in cats. Mirtazapine comes in pills and a transdermal ointment called mirataz. Mirataz is FDA-approved for cats.
Capromorelin stimulates the production of Ghrelin, a hormone your stomach produces and releases. It signals your brain when your stomach is empty and it’s time to eat. Capromorelin (Elura) comes in an oral liquid for once daily administration. It was developed to manage weight loss in cats with Chronic Kidney Disease.

Make sure your old cat eats – fasting longer than 2-3 consecutive days can result in hepatitis lipidosis, which can be fatal if not treated promptly

Keeping your older, skinny cat well-fed is essential to maintaining a good quality of life for him or her.

Warm canned food

Feed small meals frequently

Talk to your vet about an appetite stimulant if necessary.

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Arthritis in cats: a tale of biotech and a Chinese hamster

Posted on January 30, 2022 by felinepurrspective_u3q4o6

If you search for “monoclonal antibodies”, most of the search results are about COVID-19 and its variants. But did you know that monoclonal antibodies form the basis of the newest treatment for arthritis in cats? This new treatment is called Solensia. Solensia is a monthly injection for arthritic cats that won FDA approval this month. It should be available through your veterinarian later this year.

arthritis in cats: a tale of biotech and a chinese hamster

what are monoclonal antibodies?

Monoclonal: refers to a cell or organism that comes from a single individual or cell.
Antibodies are proteins in the blood that our immune system produces to counteract a foreign substance such as a bacteria or virus (think COVID-19).

antibodies and the immune system

Immune cells in our bodies called B-lymphocytes mount a response to a foreign substance or antigen (e.g. a virus), binding to it and deactivating it. The presence of the antigen and immune cells called T cells activate the B-cells. The B cells then propagate and release antibodies that are able to bind to and deactivate the specific antigen that stimulated their formation!

Monoclonal antibodies are derived from clones or copies of activated B cells. They can be harvested and grown in the laboratory and used to fight infections caused by the antigen they were developed to target.

Where do monoclonal antibodies come from?

Blood cells from convalescing patients: Due to the large numbers of convalescing COVID patients, there was a ready source of blood cells containing B-cells with antibodies to COVD 19 that could be used to make monoclonal antibodies to treat newly infected patients.
Transgenic mice: Mice that have been genetically altered to carry human antibody genes instead of mouse antibody genes are the usual source for monoclonal antibodies. These mice can be injected with a specific antigen and produce fully human antibodies that can be used by human patients to combat that antigen. Being human antibodies, they are less likely to be rejected by the human immune system.

Arthritis in cats: using monoclonal antibodies

Nerve growth factor (NGF) is a protein that is key to the development and survival of nerve cells or neurons, particularly sensory neurons that transmit pain, temperature, and touch sensations.

When NGF binds to pain receptors inside the sensory neuron, a series of events is triggered that ultimately sends a “pain” signal to the brain.

Instead of binding to a structure on a virus, monoclonal antibodies can be developed to recognize and attach to NGF, preventing NGF from binding to the pain receptors on the sensory neruron, blocking the pain signal.

Motion is Medicine

A reduction in pain means our arthritic cats will be more likely to move around more. Increased mobility will strengthen the cat’s muscles, so they can better support and assist the deteriorating joints. Increased activity and reduced pain result in a better quality of life.

Biotech Magic

The active ingredient in Solensia is frunevetmab, a monoclonal antibody that targets NGF. The antibodies are sourced from Chinese hamster ovary cells. Like the mice that have human antibodies instead of mouse antibodies, the hamster cells are “felinised”using recombinant biotechnology. Sections of the hamster antibodies are replaced with their feline counterparts. “Felinization” ensures that the cat’s immune system will not reject the monoclonal antibodies but allow them to function as part of the cat’s immune system.

Of cats and hamsters: no hamsters harmed

Frunevetmab is sourced from the cells of Chinese hamster ovaries. In fact, cells from an individual Chinese hamster, harvested back in the 1950s, produced the cell line which dominates biotechnology today. These cells are easy to propagate and maintain in the lab, providing a ready source of monoclonal antibodies.

multimodal therapy for arthritis in cats

Solensia is a pain medication and does not directly aid in preserving the synovial tissues. Most likely, Solensia will be part of a multimodal treatment that will include drugs and supplements like Adequan or glucosamine that are thought to help maintain synovial tissues in addition to weight loss and exercise.

Unlike other arthritis pain treatments such as NSAID’s, monoclonal antibodies are eliminated in the same way other proteins are, with minimal effect on the kidneys and liver, a concern for our cats with Chronic Kidney Disease.

Treatment using Solensia will consist of monthly injections under the skin. Most cat owners can become proficient in giving subcutaneous injections and treatment can be done in the safety and comfort of the cat’s home.

Thanks to a Chinese hamster years ago and advances in biotechnology, our cats may be able to spend their “ golden years” without pain from osteoarthritis!

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Arthritis Supplements for cats – do they work?

Posted on December 19, 2021 by felinepurrspective_u3q4o6

A cat receives an injection of polysulfonated glycosaminoglycans.

It is thought that almost 40% of all cats have clinical signs of arthritis and 90% of cats over age 12 have damage to the joints that you can see on x-rays. Cats are such masters at hiding pain that we are now thinking that arthritis is there earlier, pain is happening and we may not be able to see it on x-rays yet.

What if we could be proactive and start some kind of treatment before our cats even seem painful? Could we slow the deterioration of the joints? What arthritis supplements for cats are available and do they work?

The motivation behind writing this post was to help my youngest cat, 5 year old Gus, who showed some indications of spinal arthritis in his x-rays. Should I begin a supplement with him? I was astounded by the sheer numbers of arthritis supplements for cats on the market and the astounding claims they made.

arthritis supplements for cats – do they work?

Arthritis supplements for cats on the market now range from supplements used by humans to homeopathic remedies. Clinical trials are rare to non-existent on many of these products. This post addresses the more common products and ones that have had some double-blinded clinical studies done.

glucosamine/chondroitin,
omega fatty acids/ green lipped mussel extract
polysulfated glycosaminoglycans

Glucosamine/chondroitin

Glucosamine occurs naturally in cartilage, the flexible connective tissue found throughout the body – for example, in the external ears and the surfaces of joints. The supplement can be made synthetically in the lab or harvested from the shells of shellfish.

Some human studies have shown oral glucosamine may help with pain relief and slowing of joint degeneration in people suffering from osteoarthritis. However, in general, the results from these studies are not conclusive.

Dasuquin is a commercially available formulation of glucosamine/chondroitin for cats. It is a dietary supplement in a capsule that is sprinkled on food. The product has been evaluated for safety.

A recent double-blinded study of Dasuquin enrolled 59 cats with Degenerative Joint Disease.

All 59 cats were given a placebo for 2 weeks.
Then 29 cats received the supplement for 6 weeks while another 30 continued to receive the placebo.
The cats were evaluated by using an at-home accelerometer (like a kitty “fit bit”), owner observations and vet exams through out the study.
The study showed a strong placebo effect – 78% of the cats were more active while on the placebo.
Cats on the supplement did not show any statistically significant improvement over cats on the placebo.

However, the study did raise some questions:

The “kitty fit-bits” showed that the least active cats at the start of the study became more active on the supplement. Were these cat more painful to begin with?
The placebo was given in the first two weeks of the study when owner enthusiasm would have understandably been highest and owners would have been looking for improvement.

More research is needed – perhaps a different study design?

Omega Fatty acids (fish oils)

Supplementation with fish oils has shown some benefit for arthritic cats. A double-blinded study showed that cats supplemented with fish oil for 10 weeks were more active, going up and down the stairs more, jumping higher, not walking as stiffly and were more interactive with their people. This study used owner evaluation to assess the cats’ improvement.

Fish oil can be given as a dietary supplement (Welactin) or fed as a therapeutic diet, such as Hill’s j/d.

Side effects of fatty acid supplementation include GI upset and reduced blood clotting. There is some controversy over how much fish oil is enough. Additionally, fish oil can add quite a bit of calories to your cat’s diet and could result in weight gain, taxing your cat’s joints further.

Merial’s Antinol for Cats supplement is based on fatty acids from green-lipped mussel extract. There are a number of case studies where the supplement has been given to cats with good results for cardiac and dermatological issues, in addition to joint and mobility problems.

Polysulfated Glycosaminoglycans (PSGAGs)

This product is available under the brand name Adequan. It is the veterinary version of Arteparon, used in humans.

Decreases the breakdown in cartilage. The PSGAG’s allows the cartilage to hold more water, making it resistant to degradation.
Adequan has been extensively studied in dogs and horses for over 20 years and is FDA-approved for these species
Available by prescription.
Given by subcutaneous injection in cats with generally good results.

The jury is still out on most of the arthritis supplements for cats. Given at the manufacturer’s recommended dose, these products are safe and may be effective. Considering the individual nature of pain, some cats may respond favorably while others do not. Once again supplements are basically unapproved drugs so there is not the rigorous evaluation that accompanies FDA approval.

Your vet is your best resource on arthritis supplements for cats. He or she will be able to recommend a supplement or diet that is appropriate for your cat and is compatible with other medications or medical conditions your cat may have. In particular, combining supplements should be done with care – glucosamine, fatty acids and Adequan all effect how your cat’s blood clots.

So, what will I do for Gus?

My vets recommended the Adequan injection, citing the robustness of the canine studies and the fact that it is an injection – there is a greater confidence that the cat will get the supplement. We are not depending on him to eat something.

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Measuring your cat’s blood pressure: why and how

Posted on December 12, 2021 by felinepurrspective_u3q4o6

You’ve brought your senior cat in for her regular checkup and the technician asks you if you would like to have her blood pressure checked. Although your blood pressure is routinely checked when you go to the doctor, it has not occurred to you to ask to have your cat’s blood pressure checked. Should you have your cat’s blood pressure measured? How is it done – will it be uncomfortable? Frightening?

Why measure your cat’s blood pressure

As cats age, many develop hyperthyroidism and kidney disease. Other cats may develop diabetes. All of these conditions can result in the heart pumping harder to compensate for the changes. As the heart pumps harder, blood pressure increases and arteries, the eyes, the kidneys, the brain and heart can be damaged.

Left untreated, high blood pressure can result in:

blindness
increasing loss of protein through the kidneys >> shortened life span
disorientation, lack of balance, seizures, altered mentation or behavior, or weakness in the limbs

The best way to avoid these consequences is to monitor your cat’s blood pressure and start treatment if his blood pressure is high.

So how do we measure your cat’s blood pressure?

When measuring blood pressure in humans, we typically place a pressure cuff on the upper arm, inflate the cuff until the flow of blood to the artery is shut off . The cuff is then released, and a wave of blood fills the artery, turbulent at first, then subsiding to a smooth flow.

The human practitioner can use a stethoscope to listen to the sounds made as the blood rushes back into the artery.

The first sound is heard at the systolic blood pressure (the higher number in 120/80)
The final sound is heard at the diastolic pressure (the lower number in 120/80).

We will also use a blood pressure cuff to measure your cat’s blood pressure. This cuff can be put:

on the front leg
on the hind limb, above or below the hock (ankle)
on the tail

Cats’ arteries are much smaller than humans’ and it is difficult to hear the sounds of the blood flow using a stethoscope, so we turn to other methods: Doppler and oscillometric.

Doppler

A Doppler unit measures blood flow.

After placing the cuff on your cat, the Doppler sensor is placed over the target artery.
Piezoelectric crystals in the sensor detect changes in the flow of blood in the arteries and convert these to sound.
Acoustic gel on the sensor ensures good contact so that the practitioner can hear the heartbeat.
The cuff is inflated until the heartbeat is no longer heard.
The cuff is then released and the pressure at which the heartbeat can be heard again is the systolic blood pressure.
Headphones are usually used when measuring blood pressure with a Doppler.

Doppler units give us a measurement of the systolic blood pressure, the larger number in the 120/80.

Oscillometric

Only a cuff needs to be placed to measure your cat’s blood pressure with an oscillometric unit.

A sensor in the cuff detects the pressure pulses in the artery.
As the cuff is inflated, the pulses decrease as flow to the artery is cut off.
The cuff is then deflated and the pressure wave that results as the blood rushes back into the artery is analyzed.

Oscillometric units typically only measure the peak of this wave, the average blood pressure, and calculate the systolic and diastolic pressures.

A High Definition Oscillometric unit records the entire pressure wave, directly measuring the systolic and diastolic pressures. An HDO unit is usually connected to a computer to view the pressure wave and determine if the measurement was accurate.

How accurate is a blood pressure if my cat is nervous at the vet clinic?

Just like people, cats get anxious and nervous when visiting the vet clinic. Blood pressure is sensitive to this and it can be a challenge to measure your cat’s blood pressure.

Putting the odds in our favor:

Most of the time, you should be with your cat during a blood pressure measurement. Your cat knows you and trusts you. Your presence is reassuring and calming.
Allow your cat to settle in for 5-10 minutes – the measurement should be done in a quiet room.
If your cat likes to snuggle in your lap, see if the measurement can be done there. If your cat prefers to sit on his stomach, perhaps a tail measurement is best. If he is comfortable laying on his side, a hind leg may be better.
Using the front leg to measure blood pressure puts the practitioner in front of the cat; curious cats may want to take a nibble at the blood pressure cuff. I prefer that your cat be facing you, her person, who can reassure her. I feel the tail and hind leg work better.
The artery being measured, tail or hind leg, should be at the same level as the heart – so kitty should not be sitting up, but laying comfortably on his stomach or side.

What do the numbers mean?

Again, like people, the systolic pressure is ideally around 120.
Pressures 150 and over can indicate the need for medication.
Your vet may also do an eye exam, looking at the eye with an ophthalmoscope or lens. In some instances of high blood pressure, the vessels in the eye dilate and become twisted; sometimes the retina may be detached, resulting in blindness. If high blood pressure is caught early enough, blindness may resolve with treatment.

My cat’s blood pressure is high but her eyes looked OK. What next?

High blood pressure can be treated with drugs – the most common drug used is oral amlodipine. Amlodipine takes effect fairly quickly and a blood pressure can be repeated in about 10 days and the dose adjusted if needed.
Other medications such as benazepril or telmisartan may be used alongside or in place of amlodipine.

I don’t think the reading was accurate – my cat was too nervous

It is worth investing in a home blood pressure visit. A practitioner can come to your home and get a measurement where your cat feels safe and secure.

Measuring your cat’s blood pressure especially as she gets older will help keep her healthy and comfortable. Without treatment, high blood pressure can have serious side effects, including blindness, seizures, and cardiac damage.

Have your cat examined regularly by your veterinarian, as changes to the eyes or a heart murmur might warrant a blood pressure check.

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Cat dementia – Three cats and three outcomes

Posted on November 14, 2021 by felinepurrspective_u3q4o6

Identifying signs of cat dementia is not always straightforward. In the hubbub of daily life, behavior changes can be subtle and go unnoticed until they are more severe.

Changes in behavior can indicate if your cat’s mental state has changed. The acronym VISHDAAL summarizes the behavior changes we need to observe to care for our senior cats.

V = changes or increase in vocalization
I = changes in interaction with us and other pets
S = changes in sleep-wake cycle: restlessness, night time activity
H = housesoiling
D = disorientation and confusion
A = changes in activity
A = anxiety
L = learning and memory

Three cats – three outcomes

rupert, 18 year old neutered male siamese

I had two senior Siamese cats when I had my first child. A first-time mom, I was frazzled, dealing with the completely new experience of parenting and was not paying as much attention as I should have to my cats.

One day, an acquaintance asked why one of the cats, Rupert, was sitting on the kitchen counter, in a corner, facing the wall. I had been aware that he did that sometimes but when I paid closer attention, I found that he would eat in the morning, use his litter box and then spend the day on the counter, facing the wall. He would come down to eat, drink, and use the litter box but always returned to the counter.

Behavior Changes – signs of cat dementia?

I – Rupert was no longer interacting with us.
D – He seemed confused and “out of it” – sitting on the counter all day
A – His activity had changed – he did not move much from the counter

Diagnosis:

Rupert had lost quite a bit of weight, although he was eating well. My vet diagnosed him with hyperthyroidism, which was a new disease in cats at that time.

Outcome:

Use of radioactive iodine to treat the disease was pioneered about 10 years earlier but it was not commonplace. Surgery was an option but at 18 years of age, Rupert was not a good candidate for surgery and we elected euthanasia due to his declining Quality of Life.

The Takeway:

I suspect that Rupert had moderate to severe cat dementia. The symptoms were most likely apparent earlier and I just did not recognize them. Nowadays, drug therapy for hyperthyroidism is readily available – methimazole is an FDA approved treatment for hyperthyroid cats. Perhaps treatment of the hyperthyroidism would have reduced the symptoms of cat dementia enough for Rupert to have had some more time with us.

Athena, 16 year old spayed female

Athena had been slowing down over the past year, was not eating as well and was spending most of her time sleeping. We had provided her with steps to access window perches and our bed; we also provided her with a heated bed.

Behavior Changes – signs of cat dementia?

I – Although still willing to play, Athena was interacting less with us; she had previously been a “nosy, busybody” kind of cat.
A – Athena no longer went on her daily walk and was less active in general

Diagnosis:

Diagnostic blood work did not show any significant changes over the past year. Athena did not show other signs of cat dementia and would still learn new tricks when hungry for treats.

X-rays showed moderate to severe arthritis in one of her hips and knees. We decided to treat her arthritis pain with the drug gabapentin.

Outcome:

Treatment for her arthritis pain has been a game changer for her; her activity level has increased, her appetite has increased, and she is back to “being in your face” when she wants something.

The Takeaway:

Regular checkups and treatment of chronic conditions can make you and your cat happier! Some symptoms typical of dementia may be due to treatable, medical conditions.

Marley, 15 year old neutered male

cat with food puzzle — Marley works the Poker Box, a food puzzle.

Marley is a friendly, affectionate cat with good health overall. In the past several months, Marley showed some of the behavior changes that we need to monitor in senior cats.

Behavior Changes – signs of cat dementia?

I – Marley had become more clingy than usual and more interactive
D – He seemed confused when playing the nightly game of “treat toss” – he seemed to forget that he was chasing a treat!
A – He did not want to walk outside with us (which he has been doing for years).
A – He seemed anxious and a little fearful. His interactions with the other cats became timid.

Diagnosis

Marley’s senior exam and blood work did not reveal any abnormalities other than a slight decline in kidney function which could be expected at his age.

Marley appears to have some mild cat dementia. Since these changes were mild, we decided to try SAMe, a dietary supplement. SAMe has been shown to be effective at reducing symptoms of dementia in cats in the early stages of cat dementia.

Outcome

About 2 months have gone by with daily supplementation. Marley is taking his daily walk again and is not as clingy with his humans. He is no longer stand-offish with the other cats and is “catching” his treats again when we play the nightly treat toss.

A Final Word…

Cat dementia cannot be cured but it can be managed. With early diagnosis, appropriate environmental modifications, dietary supplements, therapeutic diets, and medication can help can reduce the symptoms of dementia and improve Quality of Life for both you and your cat.

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