October—December 2004 Vol. 19, No. 4

veterinarians

C o n s i d e r i n g O l d e r C a t s * Considering Page 1

C o g n i t i v e D y s f u n c t i o n Danielle Gunn-Moore, BVMSS, PhD, MRCVS,RCVS S y n d r o m e * University of Edinburgh, Scotland Page 6 here are now more elderly pet cats erally considered that cats become 'senior' than ever before. Cats are more popu­ at about 7-8 years of age and progress to U p c o m i n g T lar than dogs as pets, and improvements in 'geriatric' by 12-15 years. Interestingly, some M e e t i n g s nutrition, health care and management authors recommend that longer-lived • January 11,2005 have lead to many cats living to increasing­ breeds, such as Siamese, should be consid­ • March 13-15, 2005 ly greater ages. In the United States of ered as 'senior' when they reach 11-12 years, Page 8 America, over the last 10 years, there has while shorter-lived breeds, such as the *Adapted with permis­ been a nearly two-fold increase in the per­ Persian, may become 'senior' by 6-7 years. sion from the proceed­ centage of pet cats of over 6 years of age Table 1 shows the approximate correlation ings of the 16th Annual (from 24 percent to 47 percent), a 15 per­ between cat and human ages. Fred Scott Feline Symp­ cent increase in cats over 10 years of age, It is only by understanding how cats osium held at Cornell on and the proportion of the feline population change with age that we can try to care for July 30-August 1,2004 aged 15 years or older has increased from 5 them in ways that best support a long and percent to 14 percent.13 While less data are healthy life. To do this we need to know how available for cats in Europe, the average age their advancing age is affecting their bodies. has increased from 4.7 to 5.3 years and it is Some changes are obvious, like whitening of estimated that there are currently -2.5 mil­ hair, general decline in body and coat con­ lion 'senior' cats in the United Kingdom. dition, and failing senses (sight and hear­ Since this accounts for -30 percent of the ing). However, other changes are less obvi­ pet cat population the good management ous, and these include alterations in the of these individuals is becoming an ever physiology of the digestive tract, immune more important consideration for small system, kidneys, liver, brain, and skeleton. animal veterinary practitioners and nutri­ Thankfully, there are now an increasing tionists.45 number of studies investigating the effects Defining the Age of Senior and of aging in cats, so we no longer need to rely Geriatric Cats on extrapolation from other species. All aspects of a cat's life may affect its In order to determine the best ways to potential longevity and overall quality of care for our older cats we first need to life. However, perhaps the most important decide at what age a cat becomes 'senior,' concepts to understand involve the complex and then at what age it becomes 'geriatric.' interplay between concurrent physiological However, cats, like people, do not age con­ and pathological changes and how these sistently and chronological age does not affect the older cat's ability to maintain its always match physiological age. Some cats body weight, accommodate to changes in its show obvious signs of old age after 10 years, environment, fight off infection, and cope while others appear almost unchanged until with disease. A number of these interacting they reach 15-16 years. That said, it is gen­ factors will be discussed below. Changes in Body Weight cats of up to 10 years of age. However, particularly affect the digestion an Older animals often experience there is also increasing evidence that absorption of fats and proteins.916 changes in their body weight. It is rec­ there is a much greater tendency for There is a striking reduction in the ommended that owners keep a regu­ geriatric cats (over 10 years of age) to apparent energy digestibility coeffi­ lar record of their cat's weight and be underweight.6 9 (See Table 2). The cients as cats age. These coefficients that this is checked at each clinic visit. difference in the risk of mid-life obe­ give an indication of how much bene­ This is because significant and/or sity between cats and dogs probably fit a cat derives from its food. In cats rapid weight change can have very results from their differing lifestyles. of less than seven years the coeffi­ serious implications, irrespective of Dogs tend to be energetic when cients range from 0.8-0.9. However, the underlying cause. young, then slow down as they age. In they can be reduced to as low as 0.65 Until recently, it was assumed that contrast, cats are relatively inactive in some older cats.9 Most cats will older cats, like dogs and humans, have throughout most of their lives. It is compensate for this by increasing a significantly reduced energy probably because of this that they do their daily food intake. However, requirement, and therefore a tendency not show a significant age-related some individuals may need to toward obesity. Indeed, a slight trend decline in either MER or lean body increase their intake by as much as 25 towards a decreased maintenance mass to fat ratio.710'11 percent.9 Due to the limitation of their energy rate (MER) has been shown in Ideally, cats should be fed to main­ stomach capacity this means that they tain their optimal body weight, and need to eat many small meals a day. probably the single most important Weight loss is likely to result when ytUNE HE*,. The ultimate pur­ aspect to feeding older cats is that their more frequent meals are not offered % pose of the Cornell body weight should remain stable. or when eating is painful. To com pen­ Feline Health Center Long-term studies have shown that sate for this many older cats may ben­ is to improve the neither obesity or excessive thinness efit from being fed a highly palatable, health of cats every­ increases mortality.8 While obesity highly digestible, energy dense food where by developing methods to pre­ itself reduces life span, it also increases and that it is offered in small amount vent or cure feline diseases, and by the risk of many weight-related dis­ frequently. providing continuing education to vet­ eases, including heart disease, diabetes Many of the specific nutrient erinarians and cat owners. All contri­ mellitus (DM), lameness (often due to requirements for older cats have still butions are tax-deductible. arthritis), liver disease (e.g., hepatic not been determined. It is often Director: lipidosis), and skin problems.12 assumed that many older cats have James R. Richards, D.V.M. Many older cats experience weight some degree of sub-clinical disease, Veterinary Consultants: loss which can result from a number particularly of the kidneys. Because of Christine Bellezza, D.V.M. of different, often interacting, factors. this it has previously been recom­ Paul Maza, D.V.M. These may include physiological mended that older cats should be fed Carolyn McDaniel, V.M.D. aging changes, the presence of patho­ diets with a moderate protein restric­ Administrator: logical disease processes, or behav­ tion. However, in view of our current Michael Lenetsky ioral alterations. Weight loss is often understanding of the high protein Administrative Assistants: associated with inappetence and in requirements of cats and the reduced Kathleen Mospan digestive efficiency of old age, it is Donald Personius older cats this commonly results from Pamela Sackett reduced senses of smell and taste, now felt that inappropriate restriction Sheryl Thomas and/or oral pain associated with peri­ of dietary protein may risk the devel­ opment of protein malnutrition. That Phone: (607) 253-3414 odontal disease.13 In addition, older Consultation: 1-800-KITTYDR cats tend to be less efficient at digest­ is, of course, unless the cat has evi­ Web: www.vet.cornell.edu/FHC ing their food. This probably results dence of chronic renal insufficiency from reduced intestinal function, gas­ (CRI) when it is likely to benefit from ©2004 by Cornell University on behalf moderate protein restriction, moder­ of the Cornell Feline Health Center, tric acid production, gastric and intes­ College of Veterinary Medicine, tinal motility, and intestinal blood ate phosphorus restriction, and potas­ Ithaca, NY 14853. flow.14,15 Older cats may also have sium supplementation.17 Many compounds are currently A ll visits reserved. Permission to reprint selected por­ reduced pancreatic lipase activity and tions must be obtained in wriling. Cornell University is changes in the composition of bile.16 being studied for their potential to an equal opportunity, affirmative action educator and While these factors affect the diges­ improve the quality and duration of employer. tion of all dietary components they our cats’ lives. While more research is -2- access reduced, while still containing eeded to determine the extent of any Table 1: Shows the approximate potentially positive effects, suggested all necessary facilities. This small area age correlation between cats and compounds include increased levels can then be kept safe and constant. humans of antioxidants and free-radical scav­ Sensitivity to Thirst Cat’s Approximate j Age Human Equivalent 1 engers (e.g., glutathione, vitamins A, As cats age they have reduced sensitiv­ C, and E, taurine, carotenoids, and ity to thirst. This results in an 1 16 selenium), green-lipped mussel increased risk of dehydration, espe­ extract, various combinations of cially when combined with excessive 2 21 essential fatty acids, and many more. urination. The latter is commonly Significant weight changes should associated with either concurrent CRI 3 25* always be investigated because weight or DM, and both of these conditions 4 29 loss is often the first sign of disease. occur commonly in older cats. It is Interestingly, while many of the dis­ often advisable to feed older cats a diet 5 33 eases seen in older cats are associated with high water content. However, if with inappetence and a reluctance to cats are unwilling to eat wet food, then 6 37 eat, this is clearly not always the case. it may be helpful to try to increase Senior With hyperthyroidism and some of their fluid intake using other methods. Cat’s the mal-assimilation syndromes (e.g., D rinking can be encouraged by ensur­ 7 41 inflammatory bowel disease, or early ing constant access to water, using bot­ stage gastrointestinal lymphocytic tled water or pet water-fountains, or 8 45 lymphoma) weight loss may be by giving fishy water or chicken/meat accompanied by a good or even in­ stock (ensure that no onion or onion 9 49 creased appetite. Therefore, owners powder has been added as cats can need to know that any alteration in develop hemolytic anemia if fed too 10 53 .ppetite—be it an increase or a de­ much onion). crease—can be significant. 11 57 Changes in Immune Function 1 Geriatric Changes in Environment The immune function of all mammals j Cat’s Unfortunately, older cats often cope deteriorates with age. While there are 12 61 very poorly with changes in their daily only a few studies looking specifically routine. Their response to stress is at the effects of aging on the immune 13 65 often to stop eating, hide, and/or alter system of cats, these studies do appear 14 69 their toileting habits. Any change with­ to confirm that this is the case. Older in the environment, the family, or even cats have significantly lower numbers 15 73 the diet can act as a source of stress. of total white blood cells (particularly Because a diet change can, in itself, be CD4+ lymphocytes), while neutrophil *From then add 4 years for every year stressful, it is important to make counts are raised.19 These changes are changes slowly, gradually introducing likely to result in a reduced ability to of bladder disease include increased the new food in a separate bowl, while fight infection or to screen for neoplas­ frequency of urination, straining to keeping the old food available. tic cells. This may explain the urinate, blood in the urine, or a Unfortunately, in some very easily increased risk of neoplasia in older blocked urinary tract. In cats under 10 stressed cats diet changes cannot cats. While studies are still at a very years of age a bacterial cause is found always be made. Because many older early stage, a number of dietary com­ in only 1-2 percent of cases.24,25 In the cats experience difficulty coping with ponents are being investigated for their majority of these young cats no obvi­ alterations in their environment it is potential to support or even improve ous cause can be found (although important to consider this when plan­ the immune function of older animals stress and diet may play a role), and ning changes. Where possible these (e.g., vitamins A and E, selenium, zinc, some are found to have bladder stones. should be kept to a minimum, and magnesium, and co-enzyme Q10).20'23 However, the situation in older cats hen they have to be made they The age-related risk of infection can with cystitis is very different, with should be made slowly and with much perhaps best be demonstrated by look­ almost 50 percent of cats over 10 years reassurance. Some geriatric cats ing at the age-related incidence of bac­ of age having a bacterial cause for their become progressively senile. These cats terial cystitis. Clinical signs suggestive may benefit from having their area of bladder inflammation.26,27 Some of - 3 - these infections are related to the gen­ quently in older cats. This probably and the diagnosis and treatment ai eral immune senescence associated reflects the fact that older cats have sig­ often complicated by the concurrence with age. However, the majority are nificantly lower blood and urine pH of multiple interacting disease process­ associated with CRI or DM, both of levels, and this reduces the risk of stru­ es. Prompt and full investigation is which are diseases that occur com­ vite urolithiasis while increasing the essential if treatment is to be success­ monly in older cats and which are, in risk of oxalate urolithiasis.28 While we ful. Unfortunately, it is not always easy themselves, both locally and systemi- do know of some of the nutritional fac­ for owners to recognize the signs of ill cally immunosuppressive. tors that are detrimental to kidney health so it is important that they Chronic Renal Insufficiency function, we are a long way from defin­ monitor their older cats for changes in ing a diet that actually preserves it. food and water consumption, body Older animals are susceptible to many weight, production of urine and feces, diseases and diet has a role to play in The Importance of Arthritis and behavior. The implementation of the cause and/or management of Interestingly, most owners list the dis­ senior health care clinics by primary many of them. Veterinary surgeons eases that they see in their older cats care veterinary practices can be very typically list the most common as kid­ in a different order to the list generat­ beneficial. While the clinics do need to ney disease, hyperthyroidism, neopla­ ed by veterinary surgeons. At the top be tailored to individual cats, in gener­ sia, dental disease, diabetes mellitus, of the list is arthritis, and this is fol­ al they should include regular and and arthritis. Arguably, the most sig­ lowed by kidney failure, deafness, thorough physical examinations nificant of these is renal failure. blindness, hyperthyroidism, bronchi­ (including assessment of body weight, Advancing age has many ways of tis, and dental problems.32 The role of systolic blood pressure, and retinal damaging cats' kidneys. Some of the arthritic pain in reducing the quality examination). In addition, a blood factors include a tendency towards of life for many older cats has proba­ sample is usually collected for bio­ mild dehydration, an increased risk of bly been significantly underestimated. chemical screening, thyroid level infection (pyelonephritis or interstitial Many owners report having to adjust assessment and hematology anr’ nephritis), and an increased risk of their house to assist their older cats; where appropriate, serological testing acute renal failure secondary to the moving food and water bowls to for FeLV and/or FIV. A urine sample adm inistration of certain drugs. It is lower surfaces, adding ramps to allow should undergo routine urinalysis, therefore not surprising that acute and easier access to favored sleeping areas, urine protein to creatinine ratio and, chronic renal failure are both seen very and placing low-sided litter boxes where possible, bacterial culture. commonly in older cats. However, within easy cat reach. The increasing Initially, most cats will only need to these are not the only causes of renal importance of arthritis in our older attend a clinic on a yearly basis. failure and we now know that there are cats is supported by finding radi­ However, those cats showing signifi­ a number of dietary factors that can ographic evidence of degenerative cant aging changes may need to attend also be detrimental to kidney function. joint disease in 90 percent of cats over more frequently for repeated reassess­ These include over-acidification of the 12 years of age.33 The cause of arthritis ment, monitoring, and treatment. diet, the addition of extra salt, the is usually multi-factorial; trauma, diet inclusion of high levels of ash, or the (obesity), and genetics all play a role. Changes in Physiology addition of too little potassium.28 31 The Recognizing and addressing these Once disease has been diagnosed it is presence of any of these factors can causes, and presence of arthritis, can important to remember that changes result in kidney failure, especially make a considerable difference to the in physiology also affect the pharma­ when fed to older cats. Interestingly, quality of an older cat's life. While cokinetics of many drugs. Most drugs some of these factors are often includ­ there is a clear role for diet and, in need to be metabolized in some way, ed in diets that are marketed to help particular, for obesity in the cause of and most drug metabolism occurs in reduce the risk of struvite urolithiasis. arthritis, a positive role of specific the liver and/or kidneys. Liver disease, Diets that are designed for this pur­ nutrients is still unclear. That said, the low levels of blood albumin (which pose should not therefore be fed to potential anti-arthritic properties of a binds to many drugs), and CRI all older cats. (That is, of course, unless a number of different nutritional com­ occur frequently in older cats. When specific diagnosis of struvite urolithia­ pounds are currently being studied coupled with mild dehydration sis has been made). Interestingly, while (e.g., green-lipped mussels and vari­ (which is common in older cats) thes. both struvite and oxalate uroliths are ous sources of chrondroitin sulphate). can result in reduced clearance rates found quite commonly in younger Senior Health Care Clinics and marked elevations in circulating drug concentrations.9 When treating cats, oxalate uroliths are seen most fre­ Many older cats develop clinical illness -4- geriatric patients the dose and dosing offer complex therapeutic options and Table 2: Shows the approximate intervals of some drugs may therefore sophisticated prescription diets it is correlation of cat age to body need to be altered. For example, the important to remember that older cats condition dose of metronidazole given for the are often poorly tolerant of the stress of treatment of suppurative cholangio- hospitalization or excessive physical Age of Cat % too thin % too fat hepatitis may need to be significantly handling. It is essential that each cat be reduced while the dosing interval of assessed and treated as an individual. In some cases investigations and interven­ aspirin given in the management of 1-2 years <10 20 thrombosis associated with hyper­ tions may have to be adapted or even trophic cardiomyopathy may need to abandoned if they are poorly tolerated be increased. However, it is not only for either medical or temperamental 2-10 years <10 20-50 drug overdose that needs to be con­ reasons. Also, once our patient's quality sidered. In humans, adverse drug of life can no longer be maintained it is >12 years 30-50 <20 reactions are two to three times more important that euthanasia be discussed common in people over 60 years of and then performed as compassionate­ appropriately, and observe them age.24 The situation is likely to be sim­ ly as possible. closely so we can keep them well for ilar in cats, so we need to be observant While it is true to say that "old age as long as possible. V when medicating our older cats. is not a disease," it is important that Treat the Individual we pay particular attention to our older cats, feed and care for them While veterinary medicine can often

References

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- 5 - Cognitive Dysfunction Syndrome: a Neurodegenerative Disease Danielle Gunn-Moore, BVMSS, PhD, MRCVS,RCVS University of Edinburgh, Scotland ( I . j ith improvements in nutrition of theories suggesting how these develop them at an earlier age than l / L S and veterinary medicine the life deposits may be associated with neu­ others. In agreement with this, age- expectancy of pet cats and dogs is rological degeneration, it is currently related cognitive dysfunction has increasing. Accompanying this grow­ believed that the accumulation of Ap been shown to vary between different ing geriatric population there is an into SP may initiate inflammatory breeds (and sources) of dogs. increasing number of pets with signs change and neurotoxicity which then The understanding of CDS in cats is of apparent senility. It is generally results in tau hyperphosphorylation, even less advanced than in dogs. accepted that cognitive and m otor per­ NFT formation and neurological dys­ Immunohistochemical techniques formance deteriorates with age, and function. In addition to Ap accumula­ have shown that while AP is constitu- experiments with cats have indicated tion as SP it also accumulates around tively expressed within cat brains, the that this deterioration usually occurs the meninges and blood vessels (ulti­ intensity of its accumulation within between 10-20 years of age. Recent mately resulting in cerebral amyloid neurons and blood vessels appears to studies suggest that 28 percent of pet angiopathy [CAA]). However, these be age-dependent, as is the develop­ cats aged 11-14 years develop at least changes are not pathognomonic of m ent of diffuse SP within the deep cor­ one geriatric-onset behavior problem, AD as SP and CAA are also seen in tical layers. To date, the investigation of and this increases to over 50 percent the brains of senescent humans who only 25 cats has been published, 23 of for cats of 15 years of age or older. did not show clinical signs of AD, and which Were over 12 years of age. These Cognitive dysfunction syndrome the brains of many aged mammals. In studies appear to show that older cats (CDS) is a neurodegenerative disease addition, hyperphosphorylated tau is are more likely to develop SP (only the resulting in geriatric-onset behavioral also present during postnatal devel­ 14 oldest cats were found to have SP). problems. The clinical signs can opment and arises in response to Our own study supports this finding- include disorientation, altered inter­ degenerative events such as ischemia SP were seen in seven of nine cats o. action with the family, changes in or seizures. over 10 years of age, but none of 10 sleep-wake cycles, changes in activity Using sensitive immunohistochemi- younger cats. Interestingly, the SP such as wandering and/or pacing, cal techniques it has been possible to appear to be even more diffuse than inappropriate urination/defecation, show that the pattern of canine Ap those seen in dogs, and quite unlike the and/or inappropriate vocalization. accumulation parallels that in humans, well developed and circumscribed SP Diagnosis is made on the basis of sev­ being age-related, with plaques devel­ that are typical of humans. While NFT eral altered cognitive signs. The cause oping in several cortical and subcorti- have not been seen in cat brains, of the syndrome in cats and dogs is cal brain regions. In Beagles, the earli­ immunostaining for hyperphosphory­ still unknown. However, recent work est and most consistent site of AP dep­ lated tau has been demonstrated, points to the involvement of disease osition is the prefrontal cortex (at occurring concurrently within the processes similar to those seen in about 9-10 years of age), with the neurons of some of the cats showing humans suffering from neurodegen­ development of SP in the parietal and SP development, and providing evi­ erative disorders, such as Alzheimer's occipital lobes at a later age. dence of possible pre-tangle formation disease (AD). Interestingly, deposition within the in four older cats. Histopathologically, there are two entorhinal cortex is not consistently While the relationship between see­ major hallmarks of AD; senile plaques observed until 14 years of age, except ing SP and/or positive staining for and neurofibrillary tangles. Senile in a subset of dogs that show signs of hyperphosphorylated tau and behav­ plaques (SP) are formed by the extra­ early-onset cognitive impairment. ioral or neurological dysfunction has cellular accumulation of the P-amy­ Studies have shown a direct corre­ not yet been well explored in cats, pre­ loid (AP) protein. Neurofibrillary tan­ lation between the extent of Ap depo­ liminary studies appear to indicate that gles (NFT) are formed by the initially sition and the extent of cognitive dys­ there may be a correlation. For 17 of intracellular accumulation of the function in dogs, with the regions of the cats previously assessed for SP the abnormally hyperphosphorylated the brain affected correlating with presence or absence of behaviora’ form of the microtubule protein tau certain types of learning and memory change was known: eight had behav­ (in its unphosphorylated form tau is deficits. Intriguingly, while all dogs ioral changes consistent with CDS; involved in forming the cytoskeleton naturally accumulate diffuse SP and seven of these were found to be posi­ of neurons). While there are a number CAA with age, some breeds appear to tive, as compared to only three of the

-6- nine cats without behavioral changes. For seven of the cats assessed for hyperphosphorylated tau the presence or absence of behavioral change was Ball, M .J., M acG regor, J., Fyfe, I.M ., known: five of these had behavioral Papoport, S.I., and London, E. Paucity of morphological changes in the brains of changes; two of which were positive for aging beagle dogs: Further evidence the tau, compared to one of two cats with­ Alzheimer lesions are unique for primate out behavioral changes. Interestingly, central nervous system. Neurobiology of amongst five cats with well document­ Aging, 1983,4: 127-131. ed CDS the severity of the behavioral Bobik, M., Thompson, T. and Russell, M.J. changes did not appear to correlate Amyloid deposition in various breeds of dog [abstract]. Abstracts in Neuroscience, particularly well with the extent of the 1994,20: 172. SP formation. Chapman, B.L. and Voith, V.L. Behavioral problems in old dogs: 26 cases (1984-1987). JAVMA, Hence, while there are many simi­ 1990,196(6): 944-946. larities between CDS and AD, CDS Campbell, S., Trettien, A. and Kozan, B. A noncomparative open-label study evaluating the effect should not be considered as a model of selegiline hydrochloride in a clinical setting. Veterinary Therapeutics, 2001,2(1): 24-39. for AD as there are a number of sub­ Cummings, B.J., Su, J.H., Cotman, C.W., W hite, R. and Russell, M.J. p-amyloid accumulation in tle differences between the two dis­ aged canine brain: A model of plaque formation in Alzheimer's disease. Neurobiology of Aging, eases. For example, as yet, NFT have 1993,14: 547-560.

not been detected in cats or dogs, pos­ Cummings, B.J., Head, E., Ruehl, W., Milgram, N.W. and Cotman, C.W. The canine as an animal sibly because they have isoforms of model of human aging and dementia. Neurobiology of Aging, 1996,17: 259-268. tau that cannot form paired helical fil- Hardy, J.A. and Higgins, G.A. Alzheimer's disease: The Amyloid cascade hypothesis. Science, ments. Alternatively, it may be that 1992, 256: 184-185. these species do not usually live long Head, E. Brain aging in dogs: Parallels with hum an brain aging and Alzheimer's disease. enough to develop NFT. Further Veterinary Therapeutics, 2001,2(3): 247-260. investigations are needed to confirm, Head, E., Callahan, H„ Muggenburg, B.A., Cotman, C.W. and Milgram, N.W. Visual-discrimina- for example, whether or not these tion learning ability and P-Amyloid accumulation in the dog. Neurobiology of Aging, 1998, changes only relate to progressive age, 19(5): 415-425. and/or to the presence of particular Head, E., McCleary, R., Hahn, F.F., Milgram, N.W. and Cotman, C.W. Region-specific age at onset of P-amyloid in dogs. Neurobiology of Aging, 2000,21: 89-96. disease processes or disorders. In addition, the extent of the changes Head, E., Moffatt, K., Das, P., Sarsoza, F., Poon, W.W., Landsburg, G. and Murphy, M.P. P- Amyloid deposition and Tau phosphorylation in clinically characterized aged cats. needs to be correlated with the clini­ Neurobiology of Aging, 2004, In Press. cal signs of CDS, and it remains to be Head, E., Milgram, N.W. and Cotman, C.W. Neurobiological methods of aging in the dog and seen whether or not particular breeds other vertebrate species. In: Functional Neurobiology of Aging. Hof and Mobbs (Ed), 2001, of cats may be predisposed. Academic Press, San Diego, pp 457-468. Treatment Options Ikeda-Douglas, C.J., Zicker, S.C., Estrada, J., Jewell, D.E. and Milgram, N.W. Prior experience, As yet, there is no published informa­ antioxidants, and mitochondrial cofactors improve cognitive function in aged Beagles. Veterinary Therapeutics, 2004, 5(1):5-16. tion relating to the successful treatment of cats with CDS. It may be possible to Levine, M.S., Lloyd, R.L., Fisher, R.S., Hull, C.D. and Buchwald, N.A. Sensory, m otor and cogni­ tive alterations in aged cats. Neurobiology of Aging, 1987,8: 253-263. consider potential treatment options by extrapolation from work with humans Moffat, K.S., Landsberg, G.M., Head, E. and Lindgren, B. An investigation of the prevalence of clinical signs of cognitive dysfunction syndrome (CDS) in cats. 2004, In preparation. with AD and/or dogs with CDS. There Nakamura, S., Nakayama, H., Kiatipattanasakul, W., Uetsuka, K„ Uchida, K. and Goto, N. Senile are a growing number of possible ther­ plaques in very aged cats. Acta Neuropathology, 1996, 91: 437-439. apeutic options for AD; these include Ruehl, W.W., Bruyette, D.S., DePaoli, A., Cotm an, C.W., Head, E., Milgram, N.W. and the use of selegiline (to manipulate the Cummings, B.J. Canine cognitive dysfunction as a model for human age-related cognitive nonoaminergic system), various decline, dementia, and Alzheimer's disease: Clinical presentation, cognitive testing, pathology cholinesterase inhibitors (to increase and response to 1-deprenyl therapy. Prog Brain Research, 1995,106: 217-225. the availability of ACh at the neuronal Selkoe, D.J. Alzheimer's disease: Genotypes, phenotype, and treatments. Science, 1997,275: 630- synapses), or antioxidants (e.g., Vitamin 631. E) and non-steroidal anti-inflammato-

-7- ry drugs (e.g., ibuprofen) to reduce neu­ essary to advise clients how best they CONFERENCES ronal damage. can manage these cases. Affected cats There have been a very small num ­ often become stressed and cope very North American Veterinary ber of studies in dogs. These appear to poorly with change: whether in their Conference-Florida suggest that high doses of mixed environment, their daily routine, their January 11, 2005 antioxidants and selegiline (1-deprenyl) diet, or the members of the household Feline infectious diseases in cat popula­ may have beneficial effects. A four year with which they live. The cat's response tions will be the focus of the Shelter study into the use of dietary antioxi­ to this stress is usually to stop eating, Medicine Track. Drs. Kate Hurley and dants (vitamin E and complex antioxi­ hide, and/or alter its toileting habits. Diane Addie will give presentations on dants) revealed significant improve­ Where possible, changes should be URI, infectious diarrhea, virulent cali­ civirus, infection control programs, ments in learning and memory. In a kept to a minimum. However, when a FIP, and other topics. For more infor­ separate study selegiline has been change cannot be avoided, it is very mation, visit: www.tnavc.org. shown to improve sleep/wake cycles important that it is planned carefully and interaction with the family after it and made slowly, with much reassur­ American Association of Feline has been given for longer than a month ance. Some cats become progressively Practitioners-Puerto Rico (0.5-1.0 mg/kg po q24h). Interestingly, more senile. These cats may benefit March 13-15, 2005 while selegiline appeared to provide from having their area of access Mark your calendars for this event. symptomatic relief, it had little or no reduced, while still containing all nec­ Details are being finalized and informa­ effect on disease progression. essary facilities. This small area can tion will be available at: www.aafpon- line.org. Management then be kept safe and constant. V Since there are, as yet, no proven med­ ical options for cats with CDS, it is nec­

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