Geriatric Medicine 2024 Mod 1, Notes W1.pdf

Geriatric Medicine rin ar y Ed uc a tio n Module: Principles of geriatric medicine pr ov e Ve te Week 1 Author: Samantha Taylor Im BVetMed(Hons) CertSAM DipECVIM-CA MANZCVS FRCVS Note: Copyright on these notes is jointly owned between the Course Speaker and Improve International Ltd and the material...

Geriatric Medicine rin ar y Ed uc a tio n Module: Principles of geriatric medicine pr ov e Ve te Week 1 Author: Samantha Taylor Im BVetMed(Hons) CertSAM DipECVIM-CA MANZCVS FRCVS Note: Copyright on these notes is jointly owned between the Course Speaker and Improve International Ltd and the material must not be copied or distributed without prior permission/authorization from either party. Improve International Ltd has taken every effort to ensure that the information in these notes and in other taught material is accurate but it cannot take any responsibility for any problems arising from errors therein. 01793 759159 [email protected] www.improveinternational.com Copyright 2022 Improve International Ltd. All commercial copying or reproduction constitutes an infringement of copyright and is prohibited. Learning Objectives n io at uc Ed y ar rin te Ve e ov Describe what geriatric means as a definition, and how life stages are allocated and why; Explain the effects of ageing on cells in general, and the expected impacts on our patients. Im pr What is Geriatric? While writing for this course the author wasn’t really sure of her own definition of the term geriatric. The author has some of her own ideas, and believes much of the public and all attendees of this module will have your own ideas, but we will discuss that definition. We will also discuss how life stages are allocated in cats and dogs and why, and if they are really helpful when we think about older pets. There are some useful, recently published guidelines. These guidelines contain useful information that will be referred back to as we go through this module. at io n The first guideline, the “Senior Care Guidelines” from AAHA for dogs and cats, was published in 2023 and the second guideline, the feline senior care guidelines, was released by the American Association of Feline Practitioners (AAFP) a couple of years ago. You will be able to find the references on your additional reading list. ar y Ed uc Both of these guidelines contain significant information on how frequently we should be assessing our senior patients and for what we should be assessing them. We will dissect that further when we come to our lesson on senior health plans, and it is recommended that you download them and have them with you, as you work through this course. rin What Does “Geriatric” Mean? Ve te Let's consider what is in a name? What do the terms geriatric and senior mean? These terms are thrown about in human and veterinary health care, but are also used in life-stage nutrition, which again will be covered later in this course. Im pr ov e The two terms are used quite interchangeably. What is the definition of senior? When do we need to change our pets to a senior diet? As this kind of allocation is quite arbitrary, we will dissect these terms. In human and veterinary medicine, geriatric tends to be a term that is reserved for illness and is associated with age-related disease. With this course, we're also interested in healthy ageing and not just lifespan, but health span, which is somewhat of a buzzword at the moment. As mentioned, in human medicine, geriatric will be used for situations where ageing has affected health and wellbeing rather than age itself. If looking at what geriatric means in Latin, the ”geras” part means old age, and the “atrics” part is related to doctors and physicians. Therefore, geriatrics seems to be a reasonable term to use, because we are all physicians, and we are looking at this particular age group. We have called this course “geriatric medicine”, because we wanted to encompass the holistic care of this age group. Additionally, the owners recognise this term, and it’s clear about the age group to which we are referring. However, you will see the term geriatric is reserved for situations associated with age related disease, rather than healthy ageing. What Does “Senior” Mean? What about the term "senior"? It’s used in lots of different situations, and some senior guidelines are already provided. This term tends to be used based purely on age, rather than any implication of illness, but the definition can vary hugely. Ed u ca tio n Exactly when an animal is classed as senior, will vary according to species and breed as well. In cats, it is an arbitrary number that has been decided by looking at the longevity of that species, and that will be discussed shortly. In dog breeds, chronological age is not necessarily as useful given the variation in longevity of that species. In general, senior tends to be associated with the last quarter of estimated lifespan, and that definition is used in some of the life stage guidelines. Ve te rin ar y Another take home message from this course, is that ageing hugely varies between individuals. That is one of the issues encountered with some of these arbitrary terms and some of the life stage discussions. Physiological changes are relatively uniform, for example, humans are probably going to age in a similar fashion, but the onset and rate of that will vary. This is particularly true between different dog breeds, but cats age with slightly more uniformity. Im pr Geroscience ov e The main questions on what each of these terms mean, is actually difficult to answer. In human medicine, there's a growing field of research looking at the older geriatric population. The human population is ageing, and this is fairly uniform as far as developed countries, although less so in underdeveloped countries. This is to do with improved nutrition and improved health care for example. Dogs are used as a model for human ageing. When we start to look at this field, there are studies where the comparisons between dogs and humans are quite strong, and the human medics are quite interested in canine ageing. This has progressed the research of this area in dogs. The canine and feline population are also ageing, and owners have sometimes quite unrealistic expectations of longevity. Often when we discuss with some feline clients, that the average lifespan of cats might be 12 to 14 years old, they feel this is shockingly low, and we believe that all cats will live until they're 18 to 20. The same is true of dogs, particularly larger breeds which, unless people are familiar with them, are often shocked by their much shorter lifespan compared to smaller breed dogs. io n Pet owners are very willing, in general, to treat senior pets for disease. The human / animal bond will be discussed in a later lesson, but it’s clear that they are very attached to their senior pets. However, on the flip side of that, there are still some misconceptions, particularly of feline medicine with "he's just getting old”, “of course he's slowing down”, “of course he's losing muscle”, “getting thinner”, “not moving". This perception can be a problem and a barrier to health care and assessment, whereas there may be underlying illness. rin ar y Ed uc at With this group of patients, we almost need to be better at communicating; discussing ageing frankly, and discussing the health issues associated with that. We need to really explain, and this is particularly true of senior health care, when patients are perceived to be healthy, but we want to get them in the clinic. We need to explain the benefits of maintaining healthy ageing, rather than reacting purely to illness, and that is a particular issue in cats where we have owner reluctance to bring them into the clinic. te Caregiver Burden ov e Ve Let us introduce the concept of caregiver burden. Caregiver burden is a really interesting phenomenon with which even the author was not familiar until relatively recently, when the author started to look at compliance in cats, and the ability of owners to give tablets. Im pr Caregiver burden is basically the stress and the burden that caregivers can feel when they have pets that are ill, and we cannot underestimate how stressful that can be to owners, particularly cat owners and how stressful they find it to give medications, but the same can be true with older dogs as well. We are likely to encounter co-morbidities and we need to consider the financial and mental wellbeing burden that this gives to our owners. Here, we just wanted to introduce that as a concept, but it doesn't mean that many of our owners are not willing to spend money and do more for their pets. Frailty We will now introduce another concept to you, the concept of frailty. This concept will be introduced in this module and will also be discussed a little bit more on the nutrition module. The concept of being frail is not a new one. We consider our aging grandparents as becoming increasingly frail, for example, and see patients in our clinic that we would describe as frail, but actually frailty is, in itself. a concept, and a description of a clinical status. It is used in human geriatric medicine, and basically describes a decline in the ability of a person to not succumb to illness, a decline in physiological reserves and an increased vulnerability to stresses. There are frailty indexes that are used in humans, and they use them to predict the likelihood that people will require health care and the likelihood that they will fall, for example, and injure themselves. In summary, it's a way of assessing risk so the intervention can be chosen to prevent illness and injury. io n This has been evaluated in dogs, because they are also looking at mirroring this with human ageing. There is also some interest in frailty indexes and this sort of numbering allocation to cats as well. at In humans, and also in cats and dogs, it's based on current clinical data and laboratory results. rin ar y Ed uc It’s important to understand that frailty is not the same as normal ageing. There is normal ageing and deterioration in function, and frailty is an exaggeration of that, which makes the patient vulnerable to illness and injury. Also importantly, it is a reversible condition, and this is why it receives so much attention in human medicine. It is associated with particularly physical weakness and unintentional weight loss, for example, but also cognitive dysfunction, which is something that will be explored frequently in this course in both dogs and cats. ov e Ve te Frailty is also significantly associated with poor outcomes, and it's something that should be detected. This should be present in our minds when we are going into clinic, working and seeing patients, identifying these frailer animals, that may have got necessarily at that point a clinical illness, although they may have co-morbidities as well, but it means that we can put in measures to try and reverse it. - Im pr Note: There is also a concept sort of pre- frailty. Frailty Scale Below you can find the frailty scale, that is in the 2021 senior care guidelines for cats and there are similar scales available for dogs. The phenotype of how the cat looks in front of you, as well as a frailty index can be used and particularly that comes from human medicine. The frailty phenotype looks at weakness, unintended weight loss, exhaustion and slowing down. The frailty scales will also take into account cognitive decline, and there are a number of cognitive tests that are used in humans to make this assessment of frailty. n io at uc Cycle of Frailty ar - y Ed Table: Frailty scales from the 2021 AAFP Senior Care Guidelines ov e Ve te rin We start with robustness, and that is the point that robustness changes to pre-frailty. If we can detect pre-frailty, because of the reversible nature of the condition at this point, we can prevent frailty and the associated negative impacts on the patient. It goes from robustness to pre-frailty, and then to frailty. There are a number of changes that play into that. Chronic under-nutrition is one, which is I think a particular issue in some of our older cats and dogs, and inflammation and inflammatory cytokines associated with ageing, so called “inflammaging”. Im pr Frailty makes our patients much more susceptible to disease. This particularly applies to infectious diseases, because we know that frailty can contribute to a poorer immune system, immune system ageing and reduced function. Frailty also leads to increased co-morbidity and increased mortality. In human medicine, the circle of frailty is used when discussing frailty. Chronic under nutrition and reduced activity contribute to frailty, which results in reduced muscle mass, contributing to reduced activity, contributing to frailty, contributing to reduced muscle mass. You can see how that can go in a circle. Having a reduced muscle mass and proteolysis can result in inflammation, and also reduce insulin sensitivity. All of which again are going to contribute to co-morbidity. We will further explore this concept in later modules. What is Ageing? This is another important question. It is important to know the difference between chronological ageing and biological ageing. Chronological ageing, based on years of life, is what we traditionally use to describe ageing in our pets. Their biological ageing may not actually be the same. Another term that we are going to introduce is senescence - another term for biological ageing and ageing of the cells. - Ageing is not a disease ‘Healthy’ ageing rin - ar y Ed uc at io n Ageing is not a disease, it is a progressive, normal and expected loss of physiological integrity, leading to functional impairment, which is a long way of saying a normal, progressive decline. That decline may be something that we can slow. We are not able to stop the passage of time but there are ways to improve the journey through this process. As physiological age increases, so does the likelihood of disease. We are certainly going to have to treat diseases along the way. e Ve te Another important concept is the concept of healthy ageing, which is what we want to encourage. We are not going to keep our pets as the vibrant, young adults that they were, but factors such as greying of the fur in the absence of clinical disease, we would call a healthy ageing feature. Im pr ov Currently in veterinary medicine, lecturing is based around clinical disease and presenting signs rather than normal ageing changes. This is the concept of health span versus lifespan. It’s unlikely an owner would prefer their pet to have a very long lifespan of ill health, rather than a period of their pet being healthy. Signs of healthy ageing include greying of the coat, thinning of the coat, some sensory loss, such as moderate hearing loss, a reduction in activity, all of which are to be expected and are not accompanied by underlying illness. Nuclear sclerosis is an example of a normal ageing change, which shouldn't significantly affect vision. This, and other sensory changes, such as reduced hearing and smell are part of healthy ageing and should not affect the animal’s quality of life. Biochemical changes (biological) in our geriatric patients are expected, as for example, in some older dogs, we may see some increases in various organ parameters. In cats, there is some evidence that, for example, urea may slightly rise with age. Normal ageing causes changes to body systems. In dogs, stable lipomas are interestingly on that list as a feature that can be seen in healthy ageing, and also, for example, the nails becoming more brittle, which are not pathological, but a normal ageing change. Changes in sleep patterns can also occur in our ageing pets, and this can be symptomatic of cognitive dysfunction. Some cognitive and behavioural changes could be considered part of healthy and normal ageing, so it relates to owner expectations. Sometimes the owner's expectations don't share the reality of having an ageing pet that doesn't quite fit in with their lifestyle. Lifespan - What lifespan Can We Expect in Dogs? Ve te rin ar y Ed uc at io n What lifespan can we expect? I think this is important to consider as we need to ensure that the owner's expectations are realistic. As discussed before, chronological age may not be very useful and we would rather consider biological age. However, owners do want to think about how long their pets will live for, and we need to know this when we think about life stage health care. Dogs have greater a genetic diversity than cats. Mixed breed dogs live 1.2-1.8 years longer on average. Artificial selection has changed the size of dogs greatly, considering for example, a Great Dane versus a Chihuahua, large breed dogs have a shorter lifespan, and a higher risk of cancer than small breed dogs. In one particular study from about 10 years ago, it showed that the average lifespan of Great Danes was about 6.5 years, which if you are the owner of a Jack Russell, would seem terribly low. Small breeds can live five to eight years longer than large breed dogs and this is due to the fact that they are ageing at a different rate. This is really interesting, because it’s believed to be related to an accelerated growth in large breed dogs that also accelerates the ageing process. Im pr ov e The lifespan is something that is studied as part of a kind of one health to look at human medicine. Mixed breed dogs generally live longer than pure breed dogs, and some of the longest-lived breeds in a British study using the vet compass data, were Miniature Poodles, Bearded Collies, Border Collies, and Miniature Dachshunds. The shortest lived dogs were the Dogue de Bordeaux and Great Danes in that particular study. The most common cause of death in some of these studies that have looked at dogs, were neoplasia, musculoskeletal and neurological disorders. Ageing has also been categorised as a cause of euthanasia, which seems a little unfair. - What lifespan Can We Expect in Cats? What about cats? If we look at some data from the U.S, the average lifespan of cats was around 12 years and if we look at the UK vet compass data, it was about 14 years, however we know that cats can live up to around 30 years and there are some extremes where cats are reported to live much longer. There is a difference in lifespan between purebred and mixed breed cats, with mixed breeds living longer. In the UK vet compass data, 91% of the cats were mixed breed. The average lifespan of cats will differ around the world depending on whether purebreds are more prevalent. The greater genetic diversity that is seen in the mixed breeds helps with longevity, and the same is true in dogs, so being of mixed breed is associated with living longer. Cats have a bi-modal pattern of decline and deterioration, and the cause is related to the fact that many cats, that are younger than five years of age and have outdoor access and are lost to trauma. The other peak is later where we lose them as a result of things like renal disorders and neoplasia. n A dog year is 7 human years, right? io - Im pr ov e Ve te rin ar y Ed uc at There is another concept of a dog year being the equivalent of seven human years. Owners find this quite useful, and they like to calculate how old their dog is in human years. Actually, we really must scale this according to size, because as you can see on this image below, taken from the American kennel club guidelines, a 16-year-old giant breed would be the equivalent of a 120-year-old human. This type of scaling can be very useful as a concept to move people away from the classic “one dog year is seven human years” concept. n io at uc Ed y ar rin te Ve e Im pr ov Does this scale give owners a reason to stop treatment and elect for euthanasia because they perceive their pet as being incredibly old? If the owner does not perceive their pet as being old because of the calculation, are they then reluctant to consider euthanasia, for example? Owners may place a lot of weight and emphasis on chronological age. Note: Lifespan is going to be affected by breed, for example, if we consider an ageing brachycephalic, we know that they have their own issues that may shorten their lifespan. - But cats have nine lives, right? What about cats with their nine lives? This very popular concept to compare human age to cat age, and the author is certain of that, because the international cat care poster on life staging and ageing in cats, that you can find an adaptation below, is one of the most downloaded and visited parts of the website. People love to look at this and consider how old their pets are. e ov Im pr y ar rin te Ve uc Ed n io at This chart can be useful for owners and can contribute to their empathy and understanding of their ageing cats. We know that in cats, comparing to dogs, there is still a big healthcare gap, and so perhaps owners considering their 14-year-old cats to be the same as a person in their mid-seventies,, will help them to understand that they require more healthcare and maybe some adjustments in the home, such as adding a litter tray. Life Stages - “Life Stages”: Good or Bad Idea? What about life stages? uc at io n We discussed some cat life stages, but there is also dog life-stage health care. This is mainly based on nutrition and on the food companies, for example, but that is not what we are actually referring here. We are referring to evidence-based division of a pet's life span. y Ed So why do we need to do it and how is it helpful? There are advantages to organising a dog or cat's life into various life stages, and there are a couple of guidelines, that you can find on the additional reading list. By accessing them you will be able to look at this in more detail. Im pr ov e Ve te rin ar By allocating life stages, it recognises that both species change as they get older, and it encourages consideration of the ageing and the normal physiological processes. Applying a framework to a pet's life can be quite sensible and logical while communicating with owners. Again, it moves away from this arbitrary chronological age allocation, although this is used to allocate life-stage in cats. If we follow our life stages in dogs, then that will vary obviously according to breed. You will confirm this ahead in this lesson, but this allows us to communicate with owners about where their pet is in the life stages and therefore what preventative health care or interventions they might require. However, as with chronological age, there is still a concern that it's arbitrary, individuals will age differently, and it isn't that they've reached a certain age and suddenly jump into the next stage and require different health care. This means that there is a blurring of those lines, and we need to adjust it to the individual. -*How Do We Decide Life Stages? The evidence-base is easier in cats because of that lack of diversity. In dogs, from the 2019 canine life stage guidelines, shown below, they have defined a puppy as a period with rapid growth, and a young adult from when that growth finishes, to the completion of physical and social maturation. The guide is about three to four years old. A mature adult is defined as the period from the cessation of rapid growth and completion of physical and social maturation, to the last quarter of their life. This is going to vary between breeds. Finally, senior is defined as the last 25% of their life. n io at Life Stages in Cats te - rin ar y Ed uc Considering that a Jack Russell is going to live until it is 16, this timeline is going to be quite different to a Great Danes timeline, however, this is a guide. The author believes it's useful and believes we could do more with it in dogs, because it does move away a little bit from the arbitrary allocation based on chronological age. e Ve Cat’s life stages are more based on chronological age, because of the lack of variation between cats genetically, however we may need to consider that purebred cats do not reach the ages that mixed breed cats do. Im pr ov Adapted from 2021 AFP guidelines, you can find bellow that they have four life stages for cats, with senior being greater than 10 years. n io at uc y Ed At International cat care and ISFM, we felt that there is a second group within those seniors that we have termed super seniors. This is based on evidence which we'll show you later on in the course. e ov The Physiology of Ageing Ve te rin ar Super senior cats are more prone to various conditions and therefore require more observation. So again, you're not going to have cats jumping suddenly between senior and super senior in their health and their ageing, but it provides a framework and it seems from feedback that owners do find this quite useful. Im pr What processes result in ageing? There are various factors happening at a cellular level. There are several of advertising and research about how to prevent aging in ourselves, but time is marching on within our bodies and there are things that we cannot change. These changes are normal, they are not a pathology, although they may make pathology more likely. The changes that are happening at a cellular level, include, for example, genomic instability. Genomic instability makes sense to predispose to neoplasia so, what we are looking for in health is definitely genomic stability, because that doesn't result in errors, but reduces with age. Another effect on genomic stability or instability is known as telomere attrition. Telomeres sit on the end of chromosomes, and they help maintain that genetic stability. Research in human ageing has been completed at telomere length. Essentially, as telomeres get shorter, there will be an increase in genetic instability, meaning that it seems quite crucial that this small area of our chromosomes remain stable and in an appropriate length, in order to prevent ageing changes. io n Epigenetics is another area that we look at, mainly at our foetal development. For example, the epigenetic effects of the environment and epigenetic effects on a foetus from the mother being hungry, for example. Epigenetics is all about the expression of genes and we know that we have genes that we're not expressing at certain times, and that's a field called epigenetics. Alterations in that kind of instruction, as to what genes to express at what time, can be part of ageing. y Ed uc at Another process is the loss of proteostasis. We do not repair as well, and we would get unfolded proteins, or proteins that are damaged, which should be removed, corrected and repaired, what is less likely to happen with ageing. This results in accumulations of these essentially damaged fragments of protein and nuclear material that can cause inflammation and disease. rin ar With age, we may also be less able to detect nutrients and balance our nutrient pathways, for example, the response to insulin can be altered with age. Im pr ov e Ve te Other factors that are involved in aging, are cellular senescence, and we mentioned senescence as another word for ageing. This can be used for the whole organism, or it can be used at a cellular level. Cellular senescence is normal, and is defined as cells reaching the end of their life and getting older. These cells should be cleared and replaced. However, as we age, our clearance of these senescent cells is less efficient. Their replacement may be affected by stem cell loss, for example, resulting in accumulation of aged cells and their products causing inflammation and potentially fibrosis. Part of that is stem cell exhaustion, because our stem cells are nowhere near as good at replacing lost cells and regenerating and repairing. Another factor that is important to consider and well-studied now is immunosenescence. Immunosenescence will be discussed in more detail in the next topic. Immunosenescence and inflammageing As already mentioned, dogs have been used as a model for ageing in humans, and so changes in the canine immune system have been much better studied than changes in the feline immune system. We know that immunosenescence and what is called inflammageing may have significance on longevity, for example. From studies in dogs, it is quite consistent to see an alteration and reduction in T-cell immunity with age. This happens in the periphery, but also in the gut as we have a change in our T and B cell ratios, and also reduced MHC expression for example, which can affect a response to antigens, or antigen recognition. There are other things within the immune system, such as neutrophils and natural killer cells that are stable. Actually, in both species, we see an increase in antibody production, so an increase in serum, salivary and gut IgA. We need to think about what effect this altered T-cell immunity in particular has on the response to vaccination and we'll come back to that. io n This concept of immune system ageing is less well studied in cats, as already mentioned, but we do know that similar to dogs, there is an effect on the lymphocytes particularly in the peripheral blood, what may also be influenced by the reduction in IGF-1, which has an effect on the release of lymphocytes. Ed uc at T cells, B cells and natural killer cells seem to lower with age, and same as in dogs, IgA. Also documented in cats, IgM is higher in our older patients. In fact, it is possible that in our ageing dogs and cats, when we measure total protein, we may see an increase in globulins with a decrease in albumin. Ve Age-related Changes to Microbiota te rin ar y It has also been shown that there is an increased production of cytokines, in general, in older cats, which fits with this concept potentially of inflammation with age. However, this has not been well studied in actually either species. Im pr ov e We are now going to discuss the immune system, and particularly, in terms of the gut. We know that the microbiota is very important in health and disease, but ageing has an effect on the population of bacteria that we have as humans in our guts, and it’s the same in our small animal patients. The full significance of the changes in microbiota is unknown and there are lots of variables in humans, for example diet and lifestyle. However, there are some consistent changes that are seen as people age, and as they get very old, and reach their hundredth birthday, these changes can be associated with frailty. Particularly in humans, it seems that there is a decrease in the bacteria that produce short chain fatty acids and when looking at research on microbiota, the short chain fatty acids are hugely important in the health of our gut and possibly beyond. Having a reduction in short chain fatty acids can result in reduced mucus production in the gut, and more seriously perhaps, a reduced gut wall integrity. This can result in the escape of antigens and a proinflammatory state that, as already mentioned, may contribute to disease in elderly patients. This lack of defence against infection is likely to increase susceptibility to various bacteria, as for example, in humans to the ageing susceptibility to infections like C.Difficile that are often acquired in hospitals. In dogs and cats, there has been some study looking at the changes in the microbiota with age. With ageing in dogs, we see a shift and a change in bacterial populations, but it is not the same as what's seen in humans. The bacterial populations differ between species. When we look at cats with age, there is a change and a transition in the microbiota, but the bacterial population is different to that found in dogs and humans. So, we are still not certain of the importance of these shifts in the microbiota, and we are not absolutely sure how to intervene and even if that will be helpful. |This is certainly an area that we are likely to see a lot more research over the years. Response to Vaccination rin ar y Ed uc at io n It is clearly important, when we are providing advice to our clients, who may have a perception that their older patients, especially if they have been regularly vaccinated, do not require further vaccination. Actually, dogs seem to mount a very effective antibody response as long as they have been previously vaccinated, so it’s apparent that, if they have never been vaccinated and they are first vaccinated at an older age, there might be a reduction in response to that vaccination. This can be seen, for example in meeting criteria for successful rabies vaccine. However, if they have been vaccinated in their life, titles persist for very long periods, and it seems that the memory of those antigens remains and, when these dogs are boosted, they will have a very effective response. Ve te In cats this has not been as well studied, but again, there is evidence of adequate response in older patients, and we know that the duration of some of the antibodies that we see, for example, to feline parvovirus can be for many years. Im pr ov e Similar to dogs, the response to rabies vaccination seems to be reduced with age in one particular study. We certainly make a conclusion that our older patients are more potentially susceptible to infection due to age, as the immune system declines with age, however they can mount an effective response to vaccination. Ideally, they should have had a previous primary course, plus follow-up boosters but, either way we still should be continuing to recommend appropriate vaccination in our older pets. Normal Ageing Changes: Skin and Coat Some of the effects of this cellular ageing are shown on what we externally see and what we see internally, in our patients. It is normal to see a thinning of the coat as patients age as a consequence of an increase in telogen defluxion. We also see that greying and whitening of the coat, which is related to the lack of stem cells, caused by a lack of replacement of those cells that are producing the colour of the coat. The skin elasticity may decrease, and this can affect our assessment of dehydration for example. In cats, and dogs, we may see more brittle nails and overgrown nails. We could argue that it is normal ageing change, but it is likely related to reduced activity, which could be to do with osteoarthritic pain, for example. Cats in particular can be reluctant to extend their elbows in order to perform normal scratching activities that would remove the outer shells of their nails and prevent them from overgrowing. Interestingly, when looking at some studies about frequent reasons that pets are presented to the veterinary clinic, nails and nail care is quite a high one, as well the anal glands. Certainly, overgrown nails could contribute to changes in mobility and considerable pain. Ed uc at io n In dogs we are also likely to see that classic drying nasal planum hyperkeratosis. This can be distressing for the owners, as it can crack and look very, very dry. This dryness again maybe related to chronic dehydration, lack of mucus production, but also the underlying hyperkeratosis may be a normal ageing change. y Pathological Skin and Coat Changes te rin ar Pathological changes will also be present and, with cats, hyperthyroidism will often present with very unkempt hair coats. Dogs with hypothyroidism will present with hair loss, symmetrical alopecia and, for example, a rat tail. e Ve Osteoarthritis and pain will affect nails and mobility, but will also affect the ability to groom, particularly in feline patients. A cat that you may see with very unkempt hair coat may be a cat without underlying other pathology, but with severe osteoarthritis. Im pr ov Hyperadrenocorticism is a disease generally of older dogs and severe calcinosis cutis can be seen, but also hyperadrenocorticism can result in alopecia. There is a potential increase in pyoderma and dermatitis in our older patients. They may be predisposed to this because of an immobility; Incontinence, obesity, may all be contributing to a likelihood of inflamed skin, which can really affect quality of life. In severe cases, we may see decubital ulcers, and with loss of muscle over joints and inadequate bedding, we can certainly see soreness and elbow hygromas in dogs for example. It is very important to be vigilant about our older pet's skincare. Normal Ageing Changes: Cardiorespiratory System Dogs Mitral valve disease is a very common change seen in older dogs. In fact, a third of dogs over 10-year-old develop it. That number would increase dramatically in certain breeds, for example, Cavalier King Charles. The mean age of diagnosis of mitral valve disease is eight to ten years of age, which depending on breed, and again, we encounter this issue with chronological age versus actual age in our canine patients but, in general eight to ten years is when we may start seeing this condition. n Surprisingly, three quarters of dogs with DCM are diagnosed at age seven or over, which is quite old for some of our larger breeds that are predisposed to DCM. This reminds us that we can see that at an older age, as well as in particular breeds with predispositions, we might see much younger patients affected. Ed uc at io Some other changes that could be considered normal, but can throw us off in our imaging investigations, are an increased bronchio-interstitial pattern on radiographs, which are probably to do with some fibrosis that occurs and could reduce lung capacity. We also see heterotopic bone in the radiographs of our older dogs and that is also seen on CT, increasing with age. Ve te rin ar y We may see bronchial calcification in both species, something also particularly found with conditions as Cushing's disease. Interestingly, a very recent CT study looking at the lungs of older dogs versus younger dogs, found very little difference between them, meaning that when we move to CT we may not see the changes that we may see on radiography. e Normal Ageing Changes: Cardiorespiratory System Cats Im pr ov In cats, hypertrophic cardiomyopathy is generally a disease of our older patients. That incidence increases as the age increases. Also, the incidence of hyperthyroidism, which may have effects on the heart increases as the cat ages. Radiographic changes that we see in our older patients include increased sternal contact of the heart, where it looks like it’s “tipped” cranially. It’s seen on lateral radiographs, which is a normal finding, and we may also see redundant or torturous aorta in this species, which can be misinterpreted, for example, with a mass in the thorax. Heart Murmurs in Older Cats Heart murmurs in older cats can be quite a confusing area. We know that heart murmurs do not always mean the presence of heart disease. We also know that up to half of cats without heart disease can have a murmur. This is to do likely with the effect of stress and tachycardia resulting in more turbulent blood flow and a dynamic murmur. Equally, not all cats that have underlying heart disease can have a murmur; up to about half of them. So overall, the presence of a murmur is not particularly sensitive and specific for heart disease in cats. - Heart Murmurs in Older Cats, When to Worry io n In our older patients, murmurs may be more significant, particularly if it is a new murmur or a loud murmur, and in these cases, a follow-up is recommended. Ed uc at Confusingly, cats can have low, normal or high heart rates with congestive heart failure, however it is overall more common to be tachycardic. If an arrhythmia is detected, this is often associated with underlying heart disease and further investigation is strongly recommend. rin ar y Gallop rhythms are something that we can hear in hyperthyroid patients, but also in cats with underlying heart disease. Stress may play an important role here but it'is certainly important to follow-up if that type of rhythm is detected. ov e Ve te Overall, the incidence of congestive heart failure increases with age in cats, and although murmurs can be misleading, and we should try and reduce the effect of stress and reauscultate our patients when their heart rates are lower in senior cats. However, temper that with the knowledge that some patients will have murmurs without heart disease. Im pr Normal Ageing Changes: Dental Changes We will see some normal aging changes, for example, the teeth can look more yellow as the dentin layer gets thickened. It is not particularly related with thinning of the enamel, but the with thickening of that dentin. Additionally, the pulp cavity can shrink, and plaque can be a normal aging finding, but it should be without a presence of inflammation. However, periodontal disease it is so very common in our patients. The odds are that 80% of dogs over three years of age, and 70% of cats over three years of age, having some evidence of periodontal disease. This will increase with our patients age, and it may be higher in miniature or small breed dogs, so there is a high prevalence of dental disease in older age. Another concern, in older patients, is oral neoplasia. It can be challenging to examine the inside of the mouth of some of our patients, understandably, due to demeanour, but we certainly will want to quickly detect the presence of, for example, a squamous cell carcinoma, which can be under the tongue and quite caudal, or a melanoma in dogs, which can start very small, or even a fibrosarcoma, et cetera. We should consider a full oral examination part of our senior health care, what emphasises the importance of keeping our patients comfortable in the clinic, which will be discussed in a later lesson. Normal ageing changes: Endocrine System io n Endocrine pathology is something we certainly see in older patients. It is not a normal ageing change, but hyper/hypothyroidism, hyperadrenocorticism. Diabetes mellitus is more seen in middle to older age, and, for example, acromegaly is likely an underdiagnosed cause of that diabetes in our older cats. Other endocrine neoplasias; adrenal, parathyroid, for example maybe also be seen. Im pr ov e Ve te rin ar y Ed uc at In cats without hyperthyroidism, the total thyroxine will get higher year after year if we measure it in our cats and the goitres can be present without hyperthyroidism, however those patients should be monitored for the development of hyperthyroidism and an assessment of IGF-1 and GH. In human and canine medicine shows that they may be markers of aging and may have significance, even as treatment targets to slow ageing, so IGF-1 and GH generally are lowering with age. There may be confusing here and different studies showing different results as far as hypo/hyperglycaemia in our older patients. Traditionally, it was thought that there's an insulin resistance and a lack of response to insulin with age. However, the finding of hyperglycaemia in older pets should always be investigated further, because in some studies in dogs, the result showed that they are more likely to be hypoglycaemic as they get older, so this relationship wasn’t clear.