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PANEL REPORT ON

FELINE SENIOR HEALTH CARE According to surveys conducted by the American Veterinary Medical Association Center for Information Management, the percentage of owned cats 6 years of age and older has risen from 24% in 1983 to just over 47% in 1996—nearly a twofold increase in 13 years. By designing and delivering individualized, comprehensive feline senior health care programs, veterinarians have the opportunity to positively impact the lives of a large and growing population of feline patients and owners. Although the aging process induces complex and interrelated physiologic changes that frequently complicate the health care management of geriatric cats, age itself is not a disease. For this reason, management decisions should not be based solely on the age of a patient. Many conditions that affect older cats can be acceptably controlled, if not cured, so that the quality of an older cat’s life can often be significantly improved by appropriate and timely medical intervention. Changes in senior cats occur across a fairly wide age range. Whereas many cats begin to show clinically significant changes between 7 and 10 years of age, most do so by 12 years of age. Because geriatric disorders tend to be chronic and progressive, veterinarians treating older cats

must be adept at managing and monitoring chronic disease and, if possible, preventing disease progression. As in pediatric patients, therapy and maintenance care must be tailored to meet changing needs. However, senior patients are more likely to experience multiple medical problems simultaneously. Veterinarians must carefully evaluate the risks and benefits of treating a given condition while considering its impact on coexisting problems. In addition to medical decision-making, family and ethical issues often come into play in the management of senior feline patients. Management of these patients must include special consideration of the strong

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bond that frequently exists between senior cats and their owners. The objectives of the AAFP/AFM Panel Report on Feline Senior Health Care are to promote the longevity and improve the quality of life of senior feline patients by recognizing and controlling health risk factors, detecting disease during the preclinical phase, correcting or delaying the progression of existing disorders, and improving or maintaining residual function. These guidelines are designed to aid practitioners in delivering consistently high-quality care to their senior feline patients by establishing a minimum standard of care. It is important that the program be individualized specifically for the needs of each patient; in some situations, the components may be more complex than those detailed here. From the cat owners’ perspective, the program must be affordable, manageable, and consis-

Editor’s Note: This is part I of a condensed version of the Panel Report on Feline Senior Health Care presented by the American Association of Feline Practitioners (AAFP) and Academy of Feline Medicine (AFM). Panelists included James R. Richards, DVM (Panel Co-Chair); Ilona Rodan, DVM (Panel Co-Chair); Gerard K. Beekman, DVM; Mary E. Carlson, DVM; Thomas K. Graves, DVM; Elyse M. Kent, DVM; Gary M. Landsberg, DVM; Jeanne M. Pittari, DVM; and Alice M. Wolf, DVM. Reviewers included C. A. Tony Buffington, DVM, PhD; Dennis J. Chew, DVM; Leslie L. Cooper, DVM; Robert M. DuFort, DVM; Sandee M. Hartsfield, DVM, MS; Collin E. Harvey, BVSc, FRCVS; Rosemary A. Henik, DVM, MS; Debra F. Horwitz, DVM; Francis A. Kallfelz, DVM, PhD; Sandra Manfra Marretta, DVM; Dennis M. McCurnin, DVM, MS; Elizabeth P. Noyes, DVM, PhD; Gregory K. Ogilvie, DVM; Margaret A. Scherk, DVM; Linda M. Schoenberg, VMD, PhD; James H. Sokolowski, DVM, PhD; and Charles A. Williams, DVM. The entire document is available from AAFP; call 1-800-204-3514 for copies.

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tent with their philosophy. The term senior is more acceptable to clients and implies preventive or “wellness” care, which improves the quality and length of life of older cats.

SENIOR HEALTH CARE PROGRAM Initiation of a senior health care program is recommended for cats starting between 7 and 11 years of age and should continue throughout life. Components of a feline senior health care program include regularly scheduled office visits during which a complete medical and behavioral history is gathered, a systematic physical examination is performed, and appropriate diagnostic tests are evaluated; vaccination and parasite control; and client education. Regularly Scheduled Office Visits Semiannual office visits are recommended because changes associated with aging and disease progression in senior cats can occur within a relatively short time. Cats with sig-

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nificant disease often appear healthy, and frequent serial comparisons of historical and examination findings assist in the early detection of disease. Regularly scheduled visits also allow implementation of other aspects of the senior health care program.

Complete Medical History Owners of older cats often notice health problems or behavioral changes but consider them to be age-related or untreatable and therefore not worthy of reporting to the veterinarian. For example, an owner may erroneously attribute inappropriate elimination behavior, changes in activity, or an alteration in eating or drinking habits to age, not recognizing that such changes may be associated with disease. Because changes may be subtle or insidious in onset, specific questions should be asked of owners. A questionnaire is an excellent means of ensuring that all potential problems are addressed. A monthly checklist can also be provided to owners to help them recognize health problems.

Information about past and current medical problems, lifestyle, litterbox use, and the cat’s environment should be sought. All prescription and nonprescription medications currently being administered should be recorded, and any adverse reactions should be noted. All foods being fed, including nutritional supplements and treats, should be noted, along with any changes in eating habits (including the amount consumed) and body weight.

Systematic Physical Examination A thorough physical examination should include a systematic evaluation of all organ systems, with particular attention paid to those commonly affected by disease in senior cats. If behavioral changes were noted in the history, a neurologic examination should be performed. Weight should be recorded at each visit. However, the body condition score (Table I) is a more accurate determinant of lean body mass, and its evaluation is encouraged. Almost every aging cat not receiving regular

TABLE I Feline Body Condition Score

Score

Classification

Characteristics

1

Very thin

Ribs: Easily palpable with no fat cover Bony prominences: Easily palpable Abdomen: Severe abdominal tuck

2

Underweight

Ribs: Easily palpable with minimal fat cover Bony prominences: Easily palpable Abdomen: Obvious waist, minimal abdominal fat palpable

3

Ideal

Ribs: Palpable with slight fat cover Abdomen: Well-proportioned waist, minimal abdominal fat pad

4

Overweight

Ribs: Difficult to palpate, moderate fat cover Abdomen: Little or no waist, abdominal rounding, moderate abdominal fat pad

5

Obese

Ribs: Very difficult to palpate, thick fat cover Abdomen: Distended with extensive fat deposit, no waist Fat deposits over lumbar area, face, and/or limbs

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dental care has some dental or periodontal disease. A thorough oral examination without sedation is usually sufficient to determine whether sedation or anesthesia is warranted for a more detailed oral examination. The use of an examination form, a copy of which can be provided to the client, is encouraged.

Diagnostic Testing Selected diagnostic tests performed at appropriate intervals may facilitate the detection of disease in a preclinical stage, allowing early medical intervention that may delay disease progression. For example, renal disease in older cats is often subclinical during its early stages, and owners may be unaware of subtle changes in their cat’s appetite, thirst, or urination habits. In such cases, detection of disease in the absence of laboratory data is difficult. Likewise, such other common senior diseases as hyperthyroidism can be detected earlier by routine laboratory screening. Routine testing also provides trend information for individual patients. For screening procedures to be most useful, they should be tailored to the patient, sensitive enough to detect early disease, minimally invasive, and cost effective. Indiscriminate diagnostic testing of senior patients with no clinical signs can have drawbacks. For a number of reasons, even healthy animals occasionally have abnormal test results and erroneous interpretation of values outside the normal range may lead to incorrect diagnosis and inappropriate therapy. Conversely, abnormal individuals may have test results within the normal range. As more tests are added to the profile, the likelihood that a healthy animal will receive an abnormal test result increases. Proper interpretation of diagnostic test re-

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sults requires integration of the patient’s history, clinical signs, and examination findings. Baseline or trend data can be especially helpful in these cases. Recognizing potential test interferences and methodologic idiosyncrasies will further improve interpretation of test results.

Senior Cats without Clinical Signs of Disease Based on the frequency of certain diseases in the older cat population and the goal of early intervention, selected diagnostic tests should be performed annually (most conveniently at every other office visit) in

cats with no clinical signs of disease. Diagnostic tests should consist of a minimum of the following: a complete blood cell count (including hematocrit; erythrocyte count, indices, and morphology; leukocyte count; differential leukocyte count evaluated by cytology; total protein; and platelet count); creatinine (preferred over blood urea nitrogen as a screening test because it is less influenced by nonrenal factors; however, thin older cats often have false decreases in serum creatinine because of decreased muscle mass); serum potassium; serum glucose; total thyroxine (T4; determined by radioimmunoassay); alanine aminotransferase; and alkaline phosphatase. Feline leukemia virus (FeLV) antigen and feline immunodeficiency virus (FIV) antibody testing should

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be included for cats whose infection status is not known or for cats at risk of exposure. A complete urinalysis should include physical evaluation (color, turbidity, and specific gravity), chemical evaluation (protein, glucose, bilirubin, occult blood, and pH), and microscopic examination of the urine sediment. The sample should be collected by cystocentesis. The Panel was divided regarding whether blood pressure should be routinely determined in senior cats with no clinical signs. Panelists not in favor reasoned that hypertension is usually secondary to disorders that would be revealed by other test results or examination findings. Because blood pressure is affected by environment and stress, concern arose over the harm that may be done if a nonhypertensive cat is treated inappropriately. Panelists in favor of routine measurement reasoned that the procedure is noninvasive and usually simple to perform, and even though primary hypertension is believed to be rare, its true incidence is not known. In addition, because hypertension is frequently associated with hyperthyroidism and renal failure, blood pressure determination at the initial visit may preclude the need for an additional visit should screening tests confirm the presence of either of these common diseases of senior cats.

Senior Cats with Clinical Signs of Disease In cats with clinical signs of disease, selected diagnostic tests should be performed at each semiannual visit, although the frequency of testing and the choice of tests may vary depending on the individual needs of the patient. At a minimum, semiannual tests should include the following: a complete blood cell count

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(including hematocrit; erythrocyte count, indices, and morphology; leukocyte count; differential leukocyte count evaluated by cytology; total protein; and platelet count); a complete biochemical profile (including albumin, blood urea nitrogen, creatinine, serum glucose, alanine aminotransferase, alkaline phosphatase, γ-glutamyl transpeptidase, total bilirubin, sodium, potassium, chloride, calcium, phosphorus, total carbon dioxide, and anion gap); and total T4 (determined by radioimmunoassay). It is important to fill tubes completely in order to accurately assess total carbon dioxide status; otherwise pseudometabolic acidosis will be diagnosed. It is also important to centrifuge and separate the serum promptly. FeLV antigen and FIV antibody testing should be included for cats whose infection status is not known or for those at risk of exposure. A complete urinalysis (collected by cystocentesis) should include physical evaluation (color, turbidity, and specific gravity), chemical evaluation (protein, glucose, bilirubin, occult blood, and pH), and microscopic examination of the urine. Blood pressure measurements should also be obtained at least semiannually in senior cats with clinical signs of disease.

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Vaccination and Parasite Control Vaccinations should be administered based on individual risk assessmenta and in compliance with local laws. Fecal analysis and parasite control should be undertaken for individuals at risk of exposure to internal and external parasites. Client Education Clients aware of senior changes and the benefits of preventive intervention are more likely to seek veterinary attention and comply with recommendations and suggested diagnostics. Knowledge that many behavioral changes and abnormalities are caused by underlying medical conditions that may be corrected or controlled is of extreme importance. Owners should be instructed to watch for changes in behavior; attitude; activity; mobility; food and water consumption (including how the cat consumes the food, because cats with painful mouth conditions often chew on one side, drop food, or exhibit chattering teeth); urinaa

A condensed version of the AAFP/AFM Feline Vaccination Guidelines was published in the August 1998 (Vol. 20, No. 8) issue of Compendium. For a copy of the entire document, call AAFP at 800204-3514.

Abnormal swellings that persist or continue to grow Sores that do not heal Weight loss Loss of appetite Bleeding or discharge from any body opening Offensive odor Difficulty eating or swallowing Hesitation to exercise or loss of stamina Persistent lameness or stiffness Difficulty breathing, urinating, or defecating

aDeveloped

by the Veterinary Cancer Society.

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SELECTED CONSIDERATIONS The following select points may not be widely known or followed. By no means are these points meant to encompass all aspects of the disease. Hyperthyroidism Serum total T4 is the recommended first-line screening test for hyperthyroidism. Some hyperthyroid cats have serum total T4 levels within the normal range (usually moderate to high normal). In such cases, a triiodothyronine (T3) suppression test, thyrotropin-releasing hormone (TRH) stimulation test, free T 4 analysis by equilibrium dialysis, or thyroid radionuclide uptake can aid in the diagnosis. However, free T4 levels may also be elevated in cats with nonthyroid illness (e.g., alimentary lymphoma), and measurement of free T4 is not recommended as a sin-

Common Signs of Cancer in Animalsa ■ ■ ■ ■ ■ ■ ■ ■ ■ ■

tion and defecation (volume, frequency, and location); and body weight. They should also monitor for vomiting, diarrhea, grossly visible or palpable masses, skin changes, coughing, sneezing, odors, breathing difficulty, and sleeping position (cats with breathing difficulty may only sleep in sternal recumbency). Dental care and grooming needs should be discussed during the consultation. Nutritional advice should be tailored to the patient and will depend on the cat’s current diet and health status; client preferences and economics should also be taken into account. Because screening tests for specific types of cancer are not available in veterinary medicine, owner awareness is especially important in early cancer detection (see Common Signs of Cancer in Animals). Early detection is of the utmost importance for treatment success but may be complicated by concurrent chronic illnesses or by the owner attributing warning signs to advancing age. Client education can be streamlined and reinforced with written materials.

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gle screening test. A combination test of serum total and free T4 might be advantageous. The TRH stimulation test has been associated with significant side effects following TRH administration. Hyperthyroidism is associated with increased renal blood flow and increased glomerular filtration rate. As a result, hyperthyroidism may mask underlying renal disease. The glomerular filtration rate will decrease following treatment of hyperthyroidism regardless of the treatment modality. Therefore, in addition to routine posttreatment monitoring, renal parameters should be evaluated 1 month following initiation of therapy. If renal failure is known to exist concurrently with hyperthyroidism, the treatment of choice is oral antithyroid medication used at the minimum effective dose. Renal parameters should be closely monitored during therapy with antithyroid medication.

Chronic Renal Failure The normal feline kidney has exceptional concentrating capacity, and the endpoint that indicates an adequate population of functional nephrons to prevent clinical signs of renal failure is not known with certainty. Experimental studies suggest that cats retain considerable urine concentrating ability even with dramatic reduction in renal mass; consequently, renal insufficiency may not be accompanied by isosthenuria. Some cats with renal insufficiency have urine specific gravities greater than 1.035. Still, determination of urine specific gravity—a measure of renal tubular function—is necessary to differentiate prerenal from primary renal azotemia. Significant proteinuria in the absence of occult blood and/or leukocytes in the sediment suggests glomerular leakage and can occur before there are changes in urine specific gravity, blood urea nitrogen, or creatinine.

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Potassium depletion is common in senior cats, especially those with renal insufficiency. Potassium-replete, nonacidifying diets should be fed to help control hypokalemia. Although oral potassium supplementation of all cats with chronic renal failure has been advocated by some, there is currently not enough evidence to support such a recommendation. However, oral potassium supplementation is recommended when serum potassium levels fall below 4 mEq/L. Potassium gluconate or potassium citrate can be used to correct hypokalemia, and either will correct or prevent such associated

effects as hypokalemic myopathy, reduced renal function, and anorexia. These supplements also provide an alkalinizing effect and may limit progressive renal injury. Regular testing for and correction of the following abnormalities should be included in any long-term monitoring of chronic renal failure: hypertension, anemia, azotemia, hyperphosphatemia, hypokalemia, acidosis, dehydration, pyuria, bacteriuria, and proteinuria (as a marker of progression). Decreased urine specific gravity predisposes cats to bacterial urinary tract infections. Urine culture and sensitivity testing is indicated in cats with low specific gravities because

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urinalyses do not always detect these infections. Pyelonephritis requires a minimum of 4 weeks of appropriate antimicrobial therapy. Chronic renal disease in many cats can be successfully controlled for months or even years. Treatment options to consider in the management of chronic renal failure include prescription diets low in phosphorus and protein; H 2 blockers such as famotidine to reduce nausea, increase appetite, and control vomiting (cats may be nauseous even if they do not vomit); intravenous fluids for decompensated chronic renal failure; client administration of subcutaneous fluids at home; antihypertensives such as amlodipine; erythropoietin; intestinal phosphate binders; potassium supplementation; calcitriol; and sodium bicarbonate.

Hypertension Systemic hypertension in cats is usually secondary to chronic renal disease or hyperthyroidism. Approximately 65% of cats with chronic kidney disease have elevated systemic blood pressure; hypertension associated with this disease requires long-term antihypertensive therapy. Hypertension associated with hyperthyroidism does not require longterm antihypertensive treatment if the hyperthyroidism is corrected. Less likely causes of hypertension include anemia, hyperadrenocorticism, and primary hypertension. Indirect systolic blood pressure measurements are reliable and noninvasive and can be obtained in the clinic via the Doppler method. b Multiple measurements (at least five readings) are recommended. Most veterinarians believe that treatment should be instituted if systolic blood pressure is higher than 170 to 190 mm Hg. Blood pressure should be taken prior to venipuncture, with b Doppler Flowmeter Model 811, Ultrasonic Doppler Flow Detector, Parks Medical Electronics, Aloha, OR.

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the patient as free of stress as possible. Using a headset and inflating the cuff slowly can minimize fear in the patient. Accurate placement of the cuff and selection of the correct cuff size are important in achieving valid measurements.c Limb and cuff size used should be noted in the medical record. The clinical signs of hypertension are usually caused by damage to target organs with a rich arteriolar supply (e.g., ophthalmic, renal, cardiovascular, and cerebrovascular tissues). Ocular signs include retinal hemorrhage or hyphema, retinal detachment, and blindness. Hypertension may worsen existing kidney disease by causing a continued increase in glomerular filtration pressure. An acquired cardiac murmur can be secondary to hypertension, and compensatory cardiac hypertrophy can occur. Cerebrovascular hemorrhage can result from severe hypertension, causing seizures, ataxia, or sudden collapse. Therapeutic agents include β-blockers, angiotensin-converting enzyme inhibitors, and calcium-channel blockers. Amlodipine has been used with wide success and minimal side effects in the treatment of feline hypertension.

Cancer Because of the popularity of cats and the increasing age of the feline population, the care of feline cancer patients is becoming a major component of many veterinary practices. Recent advances in feline oncology have improved treatment response rates, prolonged disease-free intervals, and increased survival times. However, many cat owners and veterinarians remain unaware that a large percentage of cats with cancer can be either cured or rendered free c Critikon Disposa-cufs, Johnson & Johnson (800-642-6748), two-pronged cuffs, sizes neonatal 2 and 3.

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of disease for significant periods of time. In addition, advances in palliative therapy and support often allow maintenance of a good quality of life for cancer patients. It should be recognized that most owners believe their cat’s quality of life is more important than is the length of life. Treatment of cancer can be approached with either curative or palliative intent. Curative intent often involves the use of such treatment modalities as chemotherapy, radiation therapy, surgery, and in some cases, immunoaugmentive therapy. Palliative therapy is designed to improve quality of life without nec-

essarily increasing survival time. Although tumor control is very important, support of the patient is imperative, and because most feline oncology patients are also geriatric patients, attention must be paid to such underlying conditions as renal failure, dental disease, and cardiac disease. In addition, treatment for gastrointestinal (GI) disorders, dehydration, uremia, anemia, leukopenia, sepsis, and other conditions that may be associated with the cancer treatment itself must be provided. Adequate pain management is another essential component of cancer patient care. Tumor invasion with subsequent tissue damage is the most common cause of pain. However, the treatment itself (e.g., surgery or radiation therapy) can also cause pain. Maintenance of appetite with appetite stimulants and provi-

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sion of instructions regarding care, hygiene, and feeding are also important. Staging is the process of determining the extent of the primary tumor and the presence of metastatic disease or paraneoplastic disorders such as hypoglycemia, hypergammaglobulinemia, and hypercalcemia. Accurate staging is necessary to determine the extent of the disease, direct the course of therapy, and provide information about the patient’s prognosis and the amount of time and money the caregiver will be required to expend. In veterinary medicine, compassionate care is the watchword of oncology. Optimum care requires the dedication of a compassionate, informed, and cohesive health care team, which includes not only veterinarians but also receptionists, animal health technicians, veterinary nurses, and all animal care personnel. Feline cancer patients usually have a dynamic course to their disease, so regular and frequent communication with caregivers is essential.

Diabetes Mellitus Serial blood glucose determination is the most accurate method of assessing the appropriateness of insulin type, dosage, and frequency of administration. Urine glucose and random blood glucose determinations can be misleading and should only be used in conjunction with serial blood glucose curves and information from the client. Subsequent single blood glucose determinations should coincide with peak insulin activity as determined by previous blood glucose curves. Further studies are needed to validate the clinical application of fructosamine and glycosylated hemoglobin in the management of diabetic cats. Clients should be instructed to monitor ap-

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petite, activity, attitude, water consumption, and urine output. Some clients can be taught to measure blood glucose at home, thereby helping reduce stress-associated hyperglycemia. There are several causes of insulin resistance in cats with diabetes mellitus. These include poor absorption of subcutaneous insulin; antiinsulin antibodies; infection, such as of the urinary tract or oral cavity; concurrent illness, such as pancreatitis or chronic renal disease; obesity; ketoacidosis; acromegaly; hyperadrenocorticism; hyperthyroidism; glucocorticoid therapy; and progesterone therapy.

Inflammatory Bowel Disease Anorexia may be the only clinical sign associated with inflammatory bowel disease (IBD). IBD should be considered after other causes of GI disease have been excluded. The following criteria support the diagnosis: clinical signs consistent with chronic GI disease; a thorough diagnostic evaluation (including feline trypsinlike immunoreactivity, cobalamin, and folate) that excludes metabolic disease and other primary GI diseases; and the presence of significant inflammatory cellular infiltrates on histopathology with failure to demonstrate other causes of gastroenteritis. Definitive diagnosis requires evaluation of GI biopsy specimens obtained via endoscopy or laparotomy. The typical histopathologic finding in IBD is increased infiltration of the lamina propria by lymphocytes and plasma cells. IBD may be present in conjunction with cholangiohepatitis and/or pancreatitis. BEHAVIOR PROBLEMS Although primary behavior problems may develop in older cats, the possibility of an underlying medical condition should first be considered. Therefore, it is imperative that the

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Feline Resources American Veterinary Medical Association 800-248-AVMA (2862); www.avma.org American Association of Feline Practitioners 800-204-3514; www.avma.org/aafp Cornell Feline Health Center 607-253-3414; web.vet.cornell.edu/public/fhc/FelineHealth.html American Animal Hospital Association 800-883-6301; www.healthypet.com The Delta Society 800-869-6898; www.petsforum.com/deltasociety

history be complete and comprehensive so that all emerging behavior and health problems can be identified. Disease, dysfunction, or neoplasia of virtually any organ system, sensory or cognitive decline, endocrine dysfunction, and conditions leading to increased pain or decreased mobility can all contribute to changes in behavior. Behavior problems may not be exhibited until numerous stimuli combine to “push” the pet beyond a certain threshold—or medical conditions may lower the threshold. For example, a fearful cat may not exhibit aggression until it is in pain (e.g., from dental disease) or less mobile (e.g., from musculoskeletal disorders). Cats with sensory decline may be less reactive to stimuli but may startle more easily when the stimuli are finally detected. Soiled litterboxes secondary to polyuria may cause litterbox aversion, which may lead to inappropriate elimination. Patients with pain secondary to arthritis may have difficulty getting to or into litterboxes. Many cats do not mark territory even if exposed to intruding cats but may begin to do so when a condition such as hyperthyroidism develops. Older cats may become more sensitive to environmental change as their ca-

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pacity to adapt diminishes. It is generally believed that, as in humans and dogs, the cognitive abilities of cats tend to decline with age. Alzheimer-type pathology, including diffuse β-amyloid plaques within the brain and its vessels, has been identified in older humans, dogs, and cats. Although atherosclerosis is rare in cats, the brains of elderly cats may become chronically hypoxic as a result of decreased cardiac output, anemia, conditions that lead to hypertension (e.g., hyperthyroidism and renal disease), and nonlipid arteriosclerosis. With age comes cerebral atrophy, ventricular dilation, a decrease in the number of neurons, and an increase in glial cells. In fact, it may be extremely difficult to differentiate physiologic from pathologic changes and normal function from cognitive dysfunction. There are multiple neurochemical changes associated with aging in a number of species, including a fall in serotonin levels, an increase in monoamine oxidase B leading to a decline in dopamine, a decrease in cholinergic activity, a decrease in catecholamine activity, and a possible adrenergic increase, leading to a further reduction in cerebral perfusion. There is also increased production and decreased clearance of free

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radicals. A diagnosis of cognitive dysfunction generally requires the presence of one or more of the following behavioral changes in the absence of any physical causes: decreased reaction to stimuli, confusion, disorientation, decreased interaction with the owner, increased irritability, slowness in obeying commands, alterations in sleep cycles, decreased responsiveness to sensory input, increased vocalization, and problems performing previously learned behaviors. Although there are no drugs currently licensed in North America for the treatment of cognitive dysfunction in cats, drugs that help to normalize neurotransmitters that may have become depleted (such as dopamine or serotonin), as well as those that improve cerebral blood flow, hold some promise. The use of other mood-altering drugs, behavior modification techniques, and modifications to the pet’s environment may also be required to control or resolve behavior problems in older cats. For example, a cat that can no longer gain access to its litterbox may need the litterbox relocated or adjusted so that the cat can climb in and out and assume an appropriate elimination position. Similarly, cats that eliminate more frequently may require more frequent litter cleaning or additional litterboxes. Bibliography Client services for geriatric pets. Vet Clin North Am Small Anim Pract 19:187–196, 1989. Proceedings of a Symposium on Health and Nutrition of Geriatric Cats and Dogs. Topeka, KS, Hill’s Pet Nutrition, Inc, 1996. Adams I, Polzin D, Osborne C, et al: Influences of dietary protein/calorie intake on renal morphology and function in cats with 5/6 nephrectomy. Lab Invest 70:347, 1994. Andrew EJ, Bennett BT, Clark JD, et al: 1993 Report of the AVMA Panel on Euthanasia. JAVMA 202:229–249, 1993. Atkins CE: Thyrotoxic heart disease, in August JR (ed): Consultations in Feline Internal Medicine, ed 3. Philadelphia, WB Saunders Co, 1997, pp 279–285. Aucoin DP, Goldston RT, Authement J: Drug

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