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Aging Changes In Cats

The Senior Cat
Age Conversion Chart
Common Changes in the Aging Cat
Detection of Geriatric Diseases

Aging is a natural process that we all experience. It brings with it some changes that are not particularly desirable, but we can slow and control certain aspects of the aging process by undertaking appropriate interventions in a timely manner. Our objective is to inform you of some of these interventions.

The Senior Cat
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Cats age at a different rate than do humans. During the first year of life, a cat achieves adulthood. Therefore, that first year is equivalent to about 15 human years. The second year is equivalent to about 10 human years. Each year thereafter equates to about 4 human years. Any cat older than age 12 is deemed a "senior" cat. The following table compares feline and human years on the basis of this scheme:

Feline Age

Human Age

1 year 15 years
2 years 25 years
3 years 29 years
4 years 33 years
5 years 37 years
6 years 41 years
7 years 45 years
8 years 49 years
9 years 53 years
10 years 57 years
11 years 61 years
12 years 65 years
13 years 69 years
14 years 73 years
15 years 77 years
16 years 81 years
17 years 85 years
18 years 89 years
19 years 93 years
20 years 97 years


Common Changes in the Aging Cat

Many geriatric cats groom themselves less meticulously than they did when they were younger and develop mats in their hair coat. Therefore, frequent brushing (one to three times per week, depending on the cat's tolerance) is important. Brushing collects dead hair normally removed by grooming and loosens tangles before they become mats. Severely matted hair must be cut. Scissors and clippers should be used with caution; many elderly cats have thin skin that is easily cut or torn.

Geriatric cats also lose the desire or ability to sharpen their nails regularly. The nails thicken because the cat does not slough off the dead nail tissue. If the nails are not sharpened or trimmed, they will curl under the paws and grow into the footpads, causing pain, lameness, bleeding, and, in some cases, infection. This problem can be prevented by trimming your cat's nails regularly (every four to eight weeks).

Dental Disease
Dental disease is common among geriatric cats. The two most prevalent forms of dental disease are tartar buildup (with resulting periodontal disease) and resorptive lesions.

•  Tartar buildup: Tartar buildup is common in cats of any age, but geriatric cats often have heavy tartar buildup due to years of dental neglect. The tartar irritates the gums, pushes the gums away from the roots of the teeth, and fosters bacterial growth. Bacteria not only affect the mouth but also are carried through the bloodstream to other organs, most notably the kidneys (but also the heart and liver). Tartar buildup and periodontal disease are treatable with proper cleaning and antibiotic therapy.

•  Feline resorptive (neck) lesions: "Cavities" that form at the gumline (gingiva) are called cervical line lesions or neck lesions. As they form, the gums grow over them. These teeth are painful to the touch, and the cat may have difficulty eating. The only effective treatment is extraction of the affected teeth. Attempts have been made to fill these cavities, but invariably these teeth deteriorate further and need to be extracted.


Geriatric cats usually do not lose their eyesight, although it can become less acute, especially in dim light. The irises (the colored parts of the eyes that open and close in response to light) often become mottled around age 15, but this change does not affect cats' vision.

Hearing loss and deafness occur in many cats older than age 16. These conditions are permanent. Excessive wax production is another common problem. Some geriatric cats' ears need to be cleaned periodically. A wax solvent may be used once weekly or as needed.

Arthritis/Musculoskeletal Problems
Arthritis occurs in the spine or legs of some geriatric cats. It causes them to become reluctant or even unable to jump on and off furniture; they also may be hesitant to climb stairs. Their joints may be stiff just after awakening and at other times. Because simply moving around can be uncomfortable for these cats, they may spend more time sleeping or become more sedentary. These behavioral changes may be the only outward indication that a cat has arthritis. Safe drugs for treating arthritis in cats are limited, so a close examination of the affected cat and discussion of options with the owner are important. Geriatric cats, especially those with arthritis, should have easy access to food, water, and litter.

Other Common Diseases
Other diseases commonly seen in geriatric cats include diabetes mellitus, chronic kidney insufficiency, hyperthyroidism, high blood pressure, and cancer.

•  Diabetes mellitus is caused by inadequate production of insulin by the pancreas or by body cells' failure to recognize and use the insulin (i.e., insulin resistance). Insulin is required to move blood sugar (glucose) from the blood into the cells. Symptoms of diabetes include excess urine production, increased thirst, weight loss, and a ravenous appetite. Although all of these symptoms are present in cats with diabetes, you may not observe them, especially in outdoor cats that do not eat, drink, or urinate inside. You also may not notice increased thirst or urine production in one cat if you have several cats that share water bowls and litter boxes. Weight loss also may be overlooked, especially in longhaired cats. If you observe any of these symptoms, your cat's blood glucose level needs to be measured. The test result is most accurate if your cat has not eaten for at least six hours. Diabetes is a treatable disease, although treatment often requires both time and financial commitments on the part of the owner.

•  Chronic kidney (renal) insufficiency (or chronic kidney (renal) failure) results from the slow deterioration of kidney function over many years. Kidney infections, certain toxins, and congenital diseases may contribute to this deterioration process, but aging is the main cause. In many cats, the kidneys are the first organs to fail. Cats with chronic kidney insufficiency produce an excessive amount of urine because the kidneys lose their ability to concentrate the urine by recirculating water back into the body. Because these cats excrete a larger than normal volume of water via their urine, their urine appears pale yellow and their thirst increases. As the disease progresses, many cats' appetite decreases and they gradually lose weight. Chronic kidney insufficiency can be diagnosed with simple blood and urine tests. It is manageable if treatment begins before the kidney insufficiency reaches an advanced stage. While the progression of the disease can be slowed and some of the symptoms can be alleviated with timely and appropriate care, it cannot be cured and the kidneys will continue to deteriorate.

•  Hyperthyroidism is caused by enlargement of the thyroid gland, which controls the body's rate of metabolism. When the gland becomes enlarged, the metabolism accelerates. Common first signs of hyperthyroidism are weight loss followed by an increase in appetite as the cat tries to "keep up" with his/her elevated metabolism. As the disease progresses (over several weeks to months), increased thirst and urination, vomiting, diarrhea, hyperactivity, and sleeplessness may also occur. Hyperthyroidism is diagnosed by palpating for thyroid gland enlargement and running simple blood tests. Ninety-nine percent of the time, cancer is not the cause of the enlargement, making this disease treatable and, in many cases, curable.

•  Hypertension (high blood pressure) develops in some geriatric cats. Most of the time it is secondary to chronic kidney insufficiency or hyperthyroidism, but some cats may have "essential" or primary hypertension, meaning no underlying disease is present. Essential hypertension is common in humans. Because cats' arteries are so small, special instruments are used to measure their blood pressure, most commonly one based on the Doppler principle. Hypertension is treatable.

•  Cancer is another common disease in geriatric cats. Clinical symptoms depend on the form of cancer and the parts of the body that are affected. Weight loss, anemia, lethargy, loss of appetite, vomiting, diarrhea, labored breathing, and coughing are all common signs, but any one cat is unlikely to experience all of these symptoms.

Detection of Geriatric Diseases

Early detection is the key to successful treatment of all of these diseases. Many of them can be controlled or cured if diagnosed early enough. We recommend that senior cats be examined by a veterinarian at least annually. These exams include taking a thorough history of your cat's past and present health; performing a comprehensive physical examination; running blood and urine panels, including specific tests for diabetes, chronic kidney failure, and hyperthyroidism; and measuring your cat's blood pressure. If the results of any of these tests signal that disease may be present, we will recommend additional diagnostic tests and procedures, including X-ray or ultrasound studies and biopsies of suspected abnormal organs or growths. If you are interested in scheduling an examination for your geriatric cat, please speak with one of our customer service coordinators.

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