Hi again, and thank you, everybody. Hopefully, you can see my screen for this next talk. So we're gonna, I kind of deal with a slightly different aspect of, of kind of controlling weight, weight management.

And this is how kind of how we deal with weight in senior patients. And here we're not just going to be talking about overweight, but also underweight and ideal weight as well. So it's kind of a slightly different aspect of the, of the sort of weight management sphere.

And like the previous talk, it's gonna be reasonably heavy on concepts. And, and the kind of logic behind them as well as some of the evidence, because what I'm hoping to do is by giving, by using those concepts, I'm going to be giving you good strategies that you can apply not just to individual cases, but kind of any of the cases you see. OK.

So there'll be concepts there that I'm going to introduce for you which might be new. I'll talk about the science behind those concepts, but I'm gonna try to make it as practical as possible. So like with our first talk, there's gonna be some clinical cases in there to try to illustrate how we've used those concepts in practise.

So before we get into the main talk, I just want to introduce a key concept for you which is important for ageing patients, whatever the species, senior patients, ageing patients. And that is the concept of healthspan. In the last talk, we, we obviously focused on one of the, the benefits to weight loss being life span, and that's clearly very important.

But if anything for senior patients, actually healthspan, I would argue is more important than lifespan. So what is healthspan? This can be defined as the period of life when the individual is in good health.

OK. So of course, typically the longer lifespan, the chances are there's gonna be a longer health span as well. But it it's more than just lifespan, it's not just living long, but it's also being healthy in that point.

And I guess it makes, makes the point that there's no point in extending lifespan for the sake of expanding, extending lifespan, particularly if quality of life is poor. OK. So I would argue that we should as vets be considering much more the concept of this health span rather than lifespan.

OK. Now, having introduced that, let's put this into the context of the, the topic of the the, the, the, the, the topic for the talk, which is healthy weight. OK.

So if we're thinking from a health standpoint of view. The healthy weight. Would be a point for that individual where health span is longest, you know, that's a priority particularly for senior patients because when they're getting to those autumn years, owners and we and and the animals, presumably as well want them to have, want to have as long a healthy life as possible.

OK. So we need to look at getting individuals and keeping them in a healthy weight, so we can maximise health span. Now in defining what a healthy weight is, it recognises the fact there can be deviations from, from this.

So of course, if patients gain weight, they may be in overweight condition, that's deviated from healthy weight, or if they lose weight, they're underweight. OK. And I guess our aim is to try to avoid or deal with both.

When we go from healthy weight to overweight, the negative issue that defines that is build up of adipose tissue, as I discussed in the first talk. OK. So it's that extra adequate adipose tissue that is accumulated that then links to many of the health consequences we discussed earlier on.

Shortening lifespan. Developing comorbidities, worsening existing comorbidities, negatively affecting body function and affecting quality of life. OK.

When a patient goes from healthy weight to underweight, the key concern that we need to be aware of, as I mentioned in the first talk, is loss of muscle mass. They will lose adipose tissue, but as I showed you in that first talk, that doesn't necessarily equate to poorer health. It's the loss of lean mass, muscle mass, which is important.

And you may be familiar with two terms that define this caexia and sarcopenia. These have been best defined in people, but there are, review articles covering cachexia and sarcopenia in, in, particularly in cats. So, if you're interested, we can.

Give you further details of those. OK. So that's, this is the kind of concept we're now gonna be kind of focusing on.

And I, I suppose if we want to then define this healthy weight more precisely. Based on these two negative consequences on either side. I would suggest that a healthy weight.

Is a point where muscle mass is optimal. And adipose tissue mass is not excessive, OK, cause less adipose mass tissue mass doesn't necessarily have negative consequences. I think that makes sense from what I've explained already.

OK. Sorry, my slides have just frozen. Give me 2 seconds.

OK, sorry for that. OK, so let's now go through what we're gonna cover in more detail during this talk. I'm gonna start by defining what I mean by healthy weight epidemiologically, using some of the published studies, particularly in cats, to illustrate where that is.

We're then going to talk about how we can use this clinically in our patients, what measurements we would use, and how and when. We'll talk then a little bit about chronic disease and the impact that has in senior patients, particularly in terms of weight and so on and so forth. And then we're gonna finish by using some example cases in order to show, illustrate these cog in action.

OK. And there are going to be 4 cases, but like the last one, we would like to have some cases to back up the evidence. So we've got here, we've got Tiger, IO, Muffin, and you've seen Sullivan already, but we'll come back to Sullivan in this talk.

All of these would be defined as being senior cats, so they range from 9 to 11 years. What constitutes senior in cats has not been firmly defined. Typically, it's somewhere after 7 years of age, because evidence from epidemiological studies suggests that things like blood blood parameters and so on and so forth and other things tend to.

an increase at that point, as, as does sort of mortality risk. That's one of the key points of mortality. OK.

So let's go through this. So we'll start, start with our epidemiological evidence. Now one thing I mentioned in the first talk that I want to come back to when it, in, in terms of mortality, risk of dying, is that whatever species you look at, typically there is a U or J-shaped relationship between.

Various parameters such as weight and body fat mass and, or mortality. OK. So for humans, I'm just going to use an example from a slightly different study from the previous talk.

Here, this was an epidemiological study involving 30 million people, so it's quite a large and robust study. They stratify people according to body mass index, which is your weight divided by your height squared. Hopefully everybody knows that.

And they looked at the hazard ratio for more, for any mortality from any cause. And broadly speaking, whichever way they, they, they put, they, they, they split this. Essentially, as you go from overweight to obese and further risk of mortality increases, but as you go from ideal weight to underweight, risk of mortality increases.

So actually the ideal weight is somewhere at the sort of 20 to 25. I mentioned for for particular comorbidities, this. Be shifted to the overweight, category.

And this is, of course, is all humans, so it includes those with and without disease, which is why the lower point is kind of lower and in the ideal range here. OK. But that's essentially the concept we have this U-shaped relationship.

And of course, for maximum health span, this is where we ideally want to be. What about cats? Well, you know, cats are similar to people and dogs, but they like to be a bit different as well.

So it's not quite as clear cut when we're looking at relationships with survival, and here now body condition score. So in this particular study, which is one from Australia, they looked at, cats from Sydney, a particular practise, and they stratified them according to body condition score, and then they looked at their lifespan. Apologies, this is very busy, but what you'll see is we've got this, this graph which has lots of bits of spaghetti on it, and then we've got some numbers on the left of the slide as well.

The spaghetti is a Kaplin Meyer graph and it's depicting, survival at cats from body condition score 3 through to body condition score 9. So each of those bits of spaghetti is a different survival curve for a different condition score. And the related numbers here in the table just focus here on MST, which is median survival time, and this is for cats from body condition score 3 through to 9.

So what you can see is like people being underweight is not a good thing. The shortest survival is seen in cats of body condition score 3 out of 9. They didn't have any 1 or 2s for this study to, in order to be able to, to to highlight it, but it's likely they're going to be in this range as well.

Then 4 out of 9. It's likely because this is an observational study that these patients with 3 out of 9 and 4 other conditions will have other comorbidities, which is what affects their survival, hence they're shorter. Interestingly, for cats, the other condition score, survival curves don't, aren't massively, massively different.

OK, so from 6 to 9, sorry 5 through to 9, they're kind of similar. And probably the shortest of all is the 9 out of 9, but interestingly, and again paradoxically, longest survival is actually in patients that are 6 out of 9. So if we were to just look at lifespan on its own.

We would say for a cat. Optimal body condition score is 6 out of 9, not 5 out of 9, not 8 or 9 out of 9, but 6 out of 9. Of course, remember though, we're not just interested in lifespan, it's health span.

So not only do they need to live longer, but they need to be healthy. The same authors actually did a study where they looked at body condition score and various diseases. I, I mentioned this study briefly in the last topic, where we talked about asthma.

And what they actually did was study various conditions, and some of them highlighted here on the screen were associated with body condition score. OK. Now, typically where there was an association.

There was either a lower risk in patients with lower body condition scores. So you see for oral cavity disease and musculoskeletal disease, the least risk of developing these conditions were in cats from sort of 3 to about 5 out of 9. So even underweight to ideal weight.

For other conditions, the relationship was slightly more U-shaped, as you can see here, with the least risk being a sort of 5 or 6 out of 9. So if you take all of those conditions together, the best body conditions score overall for preventing disease is 5 out of 9. So if we want to think about health span and where we should be aiming in terms of healthy weight, I would suggest that what we need to be working out, what we're looking for is a body conditions growing a cat to somewhere between 5 or 6 out of 9.5 out of 9 for minimising disease, 6 out of 9 potentially for lifespan.

OK, so I hope that helps. OK, it's slightly different from maybe what we would say in dogs where 4 to 5 out of 9 appears to be best. OK.

So that's, we've defined things epidemiologically. Now let's look at how we can build this in clinically in our patients. OK, so there are various tools that we can use practically in our consulting rooms in order to judge healthy weight status.

So for example, we can measure body weight. And we should be doing this each and every time a patient comes to our practise. And if possible, if they won't visit our practise, particularly for a cat, we should try and get owners to do this at home and send us the details.

OK. The body weight measurements is one. Of course, body condition scoring would be a second one, and I would recommend the 9 point system because it's most widely established.

The 3rd tool that we can use. His muscle condition score. OK, now I'm hoping that everybody knows about.

Body weight and body condition score. I'm hoping that at least some if not many of you will know about muscle condition score, so good news if you already if you already do. If not, I'll say a little bit about it in a moment.

So let's just say a little bit about strengths and weaknesses of er these. If you can only do one. I would strongly recommend body weight being your primary measure of health.

OK, so if it was not possible to do body condition score, the cat's not visiting the practise, or muscle condition score, make sure you do get records of weight. Why is weight better than those other measures? Well, firstly, we know that we can measure this accurately.

If we use electronic scales, our scales nowadays are really, really accurate to within 10 grammes. And if we calibrate them, we can be very sure that they're, they're reading something which is reliable. Added to that, and this is probably the greatest strength, they're very precise.

So if you take repeated measurements, they don't drift, it's gonna be within 1%. Whereas the other measures we use are more subjective and there's gonna be some variability. And then the final benefit and the final thing is that it's very simple, OK.

So we can get pretty much anybody can do this in the practise, so it doesn't take an expert, we can get it done at home, you know, using some bathroom scales or, for example, and it's very quick. So it's a really cheap, really accurate, really effective measure. This should be measured in every single senior patient regularly.

OK. Body condition score. Well, body condition score gives some greater strength over body weight, and I would argue using them in concert is best.

What are the strengths are there? Well, this one now correlates with body fat mass. We have evidence that the body conditions to our system does correlate pretty well with the amount of fat in the body, and it's relatively simple to do again, if people have had training, you can do this pretty quickly.

OK. There is also some evidence that it picks up changes in lean mass as well, if you use the chart properly. And that is because if you actually read the definitions that many people don't, being underweight, for example, here, 1 or 2 out of 9, does actually include a description of having reduced muscle mass, as you can see.

OK, so it will potentially pick up changes in lean tissue, remember, which is important when it comes to losing weight. OK. So there are some benefits.

The other benefit is it's been around for a long time, and we know that there's good correlations with health outcomes. I just showed you some examples of those, the association with lifespan and with other diseases as well. All of those things correlate with health outcomes.

So we have good evidence this one's actually an important one to follow. OK. Weaknesses, to be honest, a lot of people don't bother to do it.

That's a, that's one weakness there. A lot of practises don't bother and individuals don't. There's also variability between individuals, so the different observers will score slightly differently.

I think within a practise, if you can get agreement, it probably matters a bit less because changes are important. But a 9 point system takes about 10% change in weight. To actually see a difference, so it's very insensitive compared with body weight measurement on the scales where you can pick up 1% change if you need to, OK.

And the other thing is that whilst it does pick up muscle, as I mentioned, it's not great, particularly in overweight condition that you're not actually looking at muscle there at all. So you might be miss, missing changes in muscle because there's extra fat present. OK.

So this is why people have developed an added system that you build on top of your condition score called muscle condition. Here, what you do is you assess subjectively the amount of muscle mass at 4 different points indicated by arrows. OK, so it's over the sort of lumbar and thoracic spine, over the, over the scapula, over the temporal muscles, and over the the, the, the sort of the the the thigh muscle at the, at the back.

OK. And what you're doing is having, is, is palpating to actually feel how much muscle is present over certain bony prominences. And the scoring goes from A, where there's normal muscle mass through to D, where basically the patient is just skin and bone.

There's very little to no muscle there at all. And of course, B and C are somewhere in between. So it's again can be done quite quickly and I would encourage you to add this to your normal condition score, in, in any patient.

Advantage is it correlates well with lean mass. I think a second advantage in doing this on top of body condition is it's making you as a clinician think about muscle and lean muscle, which is important in senior patients. And it of course gives us the potential to pick up subtle changes in muscle loss, even in the face of a patient with obesity, where the fat mass might be obscuring that.

OK, so those are great strengths. Big decision, concerns still because it's early, and we've not yet proven that muscle mass clearly links to health outcomes like body condition score does, for example. And I did that, you can sometimes have a degree of inconsistency, so maybe just one or two of the sites might be affected differently from others, and that can make it a little bit difficult in terms of judging what, what is the key concern here.

OK. So, if we then add our kind of clinical tools onto what we've talked about in terms of epidemiology, we can judge patients now in our clinics to be a healthy weight. If their body condition score in a cat is somewhere between, you know, it's 5 or 6 out of 9, as we talked about before.

Ideally, also, if their muscle condition score is A, that would be optimal. Of course, many senior patients won't be A, so you kind of take B as a compromise, but A would be preferred. OK.

So currently, clinically, we would want to do body weight, body condition score, muscle condition score on a regular basis in the patients in order to pick up any changes. There may be other tools that we might be able to use in the future. And one actually is ultrasound.

And the technique of what we call e axial muscle ultrasound, it's effectively take, doing ultrasound over the, the sort of vertebral bodies to the, to the side of the, the 13th vertebral body and actually measuring the amount of muscle mass using ultrasound. So here we can see the sort of skin and subcutaneous structures. Here, we've actually got, the, the, the, the bottom of the 13th vertebra, and we can actually measure how much.

lenius and for that individual patient, that measurement over time can be, could potentially be helpful. This technique's been validated in both cats and dogs now. So, that's something potentially for the future, but I don't think we can run before we, we can walk.

We haven't yet proven that muscle condition score provides a clear benefit in terms of, outcomes, but hopefully, and, and logically, that would be the case, but I think we have work to do. OK, now, having talked about epidemiology and clinical tools that we can use, let's now just spend a little bit of time thinking about the impact of chronic disease in cats. And as I mentioned in my first talk, as cats get older, and this I think I argue.

It is worse for cats than dogs, they tend to accumulate chronic diseases as they go on, OK? And one of the challenges sometimes becomes that you actually have to juggle different chronic diseases, whilst at the same time trying to get this patient to age in as healthy a manner as possible. What do we mean by chronic disease and what do we see?

Well, a chronic disease, as we know, is one that takes a long time to develop. It often has multiple causes. It has a long time frame in terms of, outcome, and we can rarely cure them.

So all our treatments often are there to try to minimise the impact of that disease. And this here slide just shows a, a, a range of different chronic diseases that can be seen, and it's not exhaustive. But we have our kind of our common favourites like chronic kidney disease and hyperthyroidism, but also things like diabetes, inflammatory bowel disease or chronic enteropathy, and, low grade alimentary lymphoma.

We've also got things like arthritis, obesity as well as a chronic disease, let's not forget that, and respiratory diseases. OK. All of these then can have an impact on that cat, in the, the, it will obviously require managing these.

They can affect appetite and food intake, so it can lead to changes in weight. They can affect body condition in other ways, and of course, all of these things are going to have an impact on, on quality of life. I just want to sort of highlight a couple which are some of the most important ones for cats when it comes to healthy weight.

And the first, not surprisingly, is chronic kidney disease. We briefly talked about that at the start of the last talk, and I just want to come back, to this paper from, Lisa Freeman's group at Tufts. And if you remember with this paper, what she did was look at, cats with chronic kidney disease, and she looked at body weight at diagnosis and then over time.

And I think this illustrates something which we really need to remember. If we're dealing with a senior cat in particular with a chronic disease, we need to know what is gonna happen over time to this patient. And one thing they did, they looked at the studies is they modelled change in body weight from diagnosis, OK?

And here, if you look here, they've got sort of, well, diagnosis at day 0, and they were able to look at records, they could look at what happened before diagnosis and afterwards. And what they found was actually often one of the earliest things that predicts the presence of a chronic disease is a subtly changing body weight. So even in the sort of years prior to diagnosis, the 3 years prior to diagnosis, there was a slight change in weight of about sort of 0.5 to 3/4 of a kilogramme on average, OK.

Of course, after diagnosis. This, I'm, I'm sped up, and this is one of the key things I'll show you is linked to outcome, that loss of weight, OK? But bear in mind, and again an argument that we should be weighing our patients more regularly and all the time, is the fact that we can spot early development of chronic disease, and potentially by doing that, we might improve survival.

The other thing which I showed you in the last talk when we talked about Sullivan, remember that was the cat that was overweight and had kidney disease, is that the optimal weight for a cat for survival is somewhere around about sort of 6 or just over 6 kg. OK. So that's where their chances of dying is least.

OK. Being heavy and that is not good. Being lighter than that is certainly not good, but essentially slightly overweight is where we would aim.

OK. So bear in mind when you're dealing with kidney disease cases, if they're slightly overweight to begin with, then you don't put them on a weight plan necessarily unless there's lots of other reasons to do that, OK, because they're going to lose weight as well. If they're underweight already, then you need to be really ramping up efforts to try to stabilise that weight.

A second example I just want to highlight when we're looking at the impact of chronic disease is hyperthyroidism. And again, we know this one is going to have an effect on our condition. Hyperthyroidism affects metabolism, so there's a good reason for weight loss.

And this was a study by Mark Peterson, and co-workers where again, they looked at body weight, but also body condition and muscle condition in cats with hyperthyroidism. And they looked at these cats before the development of hyperthyroidism, so they were able to look back at records to do this. When the hyperthyroidism was first diagnosed, that's in red, and then when they were treated and became new thyroid again, that's in yellow.

And again, like with kidney disease cases, they lose weight pre-diagnosis, so once again, measuring body weight could be an early indicator. But of course with treatment, we can, they can gain weight again. So that's the first point about hyperthyroidism and weight.

They will lose weight as part of the disease, but we can actually with successful treatment, improve it a little bit. A second point, and this might surprise you, is that not all of these patients are underweight. OK.

So this was essentially cats stratified by body condition, ideal in blue, too fat in yellow, too thin in, in red, and actually about 40% of cats were. Underweight at the time of diagnosis, which means that over half were not underweight. So lack of being underweight doesn't mean the cat hasn't got hyperthyroidism.

And I just want to draw your attention to the fact that in this study, almost 20% of the cats were actually overweight and still had hyperthyroidism. You could probably spot them by changes in, their body weight before that though. OK.

And of course with treatment, and it's another thing to, to, to change, of course, those that are too thin. Decrease, so you have many more idea weight, but also some of them get fatter as well. So bear in mind a cat that is, that that is treated with hyperthyroidism might become overweight after that, and that's something we need to pay attention to.

And then the final point where they looked at muscle mass, this is the muscle condition score from A to D. Yellow is Aormal. Green is B, mild loss, blue is C, moderate loss, red is D, severe loss.

A few cats prior to weight loss had severe loss, but that muscle loss seemed to improve with treatment. but, some of them still with treatment actually do have some loss, at least mild loss or moderate loss, despite treatment. So we can't completely restore muscle.

OK. I hope those concepts will, will help now when we start now moving to the final bit of the talk, which is where I want to talk through concepts for how we can promote healthy weight in patients, depending upon. Where they are on that spectrum of underweight to overweight.

OK, so remember for perfect health span, for the best health span, we want our cats to be at a healthy weight range. And we define that obviously with a body condition score for a senior catus between 5 or 6 out of 9, and if possible, a muscle condition score of. OK.

Now if they are at that point to begin with, our priority will be to maintain them there. So we need to monitor their weight to make sure they're not losing weight or gaining weight, and we need to be doing things like body muscle condition to keep an eye on their lean mass. OK.

So that's our priority there. If they're underweight. What we should be aiming to do if possible.

Is Increase, their weight. So we try to actually feed them more than they need to see, and I hope that they will actually gain weight and go towards that healthy weight range. And of course, if they, if they, if they, if they are overweight, we want to do the opposite.

We need to bring them towards that, healthy weight range. How far we go, a little bit like in the first talk depends very much on what comorbidities there may be. But there are 3 scenarios then.

Senior cats already at healthy weight, senior cats are underweight, and those that are overweight, and we'll take them in turn, because once again, concepts differ depending on which case we're dealing with. So let's just look at the senior cats at healthy weight. And of the case examples I gave you at the start, there were two, that fitted this bill.

So Tiger and Io, actually, Io was 11 years old, that's a mistake. So Tiger was 10, Ayo was 11, 1 neutered male, one neutered female, both domestic short hair. But both on assessment, were otherwise healthy at that point.

So if we look back at Tiger's records, and one thing I think you do in a senior a patient is you want to look back at the medical history to see if there are any clues about things that may concern you. And in Tiger's case, the owner had had the, had the tiger since 4 months of age, full vaccination and parasite treatment history, and actually no major illnesses had been reported in that time. So what do we do?

We assess body weight, muscle condition, and, body condition score. And Tiger at this point was 5.46 kg.

Body condition score 6 out of 9, muscle condition score B, although some areas were A and some were B. So it's a little bit of difference. So overall, I'd be quite happy with this as a starting point.

I'm not too worried about that 609. I probably wouldn't want to do too much about it. There's no evidence that's causing any problems for this cat at the moment.

There are no comorbidities. I'm maybe a little bit worried about the BCS and B already, so it does suggest there's maybe been some condition loss, but it's not too, too much. And that 5.46, I'm going to record that now as the weight I want to maintain moving forward.

Similarly with IO again, has been present since sort of second vaccination and a kitten, did have early vaccinations, but actually hadn't come back to the vets for that, and nor had it had parasite control. There was a, a, a history, a few years previously where there was some inappropriate urination or behavioural problem that seemed to have been resolved with some initial therapy and nothing was required. IO being a female cat was slightly lighter, 3.92, and body condition score 5 out of 9.

So I'm, I'm kind of comfortable with that. Bear in mind, 5 to 6 would be what would be perfect at this range. So I'm gonna have maybe want to be a bit closer in monitoring that weight moving forward just because we're towards the lower end of what I would like as normal.

That being said, no evidence of any muscle loss. So again, that's something we can go for. So plan here, record these in the notes and do some regular, monitoring from that point on.

So what would our priorities be in terms of a senior plan for these patients? First and foremost, we'd want to be checking regularly for any evidence of the emergence of chronic diseases. OK.

So examples being things like kidney disease, hyperthyroidism, arthritis, and so on and so forth. We can get information from history, of, from the, the, the client. We can also consider doing regular blood tests to look for emergence of these diseases.

And of course, I would, if we identify any of these, then the sooner we can pick them up, the better. We would then want to treat them proactively and we may remember one of our priorities is maintaining weight. So depending on the disease, there may be system, staging systems that would help us.

So for example, things like the Irish staging for chronic kidney disease, I would make sure I make use of that, and so on and so forth. Second priority, remember, maintaining weight is key. So I'd want to be doing regular nutrition assessments in these patients.

You can use, for example, the WSAVA nutritional assessment checklist. If you go to the WSAVA website, they've got lots of resources about that. And that's a sort of formal questionnaire.

If you don't have time for that, do make sure you build in. Discussions of nutrition in all your healthy consultations. Make sure they're eating fine, they're not having problems eating, teeth problems and so on.

They're not having problems with, you know, that they're not, their appetite is not affected. You need to be sure that the owner knowing how much they're feeding to make sure it is sufficient. And added to that, I do want to think about sort of regular, checks of to make sure they stay in healthy weight.

So besides all of these things we would do on a routine basis, body weight, body condition score, and muscle condition score. How often you do this, of course, would depend upon what the owner is, is up for and of course what you can manage in your practise. I guess in an ideal world.

Body weight checks at least every 3 months will, will be very good. Remember, body weight can spot chronic disease as it develops. So I think that's really useful to, to guide you to the need to look a bit closer.

Then you can probably do muscle condition and body condition, well, possibly every 3 months if you can, if they're visiting, but then every 6 months otherwise. But of course, if there's any non-routine visit for an illness, make sure you check these then, because that's often when you spot a sudden change. OK.

Now there's little point in gathering information unless you're going to commit to doing something with it. So what I would recommend is certain intervention points based on these metrics. So if your weight from the start changes by 5% or more, so if we set our healthy weight in the records, and when we weigh this cat, it's 5% less, not from the last visit, but from that healthy weight, then that should trigger me to look a bit closer.

Certainly if body condition score is changed by a unit, remember, it takes 10% weight change for this. So you should really have picked it up with body weight before that. And added to that, any change in muscle condition score, so you might not have, you might have a stable weight, but if muscle condition has changed, that's another reason for me to want to look a bit closer.

OK. So this is what's going to guide me for the future, for these healthy patients. OK, so that's that first category.

Hopefully that kind of sets out the sort of standard of care for a senior sort of well wellness kind of plan. Now let's think about a cat that's underweight when you first see it, OK? And again, the priority is going to be slightly different here because if they're underweight, then clearly there there may be a problem already there, but also there's a greater need to try to do something about that weight as well.

So what are our priorities? Firstly, we need again to recognise, I diagnose, treat and manage any existing chronic disease, OK? Once they're stable or as part of the process, what I'd like also to do is to see if we can get them to put some weight on so that we move them towards what we think is their healthy weight.

We may not get them the whole way, but if we can get them to put some weight on, that's a good thing. As I said in the first talk, and I'm gonna emphasise more now, maintaining muscle mass, I think is probably the number one thing, OK? But doing this, #2, is at the moment the only way we've got of doing number 3.

So this means we need to make use of foods, drugs, and, if necessary, interventional nutritional support whenever needed in these patients. OK. So what sorts of things can this be?

Well, I'm not gonna go through all details, but foods might be therapeutic diets depending on the condition. They may be standard, complete and balanced diets for a senior pet. Again, there are wet and there are dry versions.

I'm not going to sell you any particular products. And sometimes you may need to use make use of palatable foods to get that patient eating if, if not eating is one of them. OK, so food is really important.

Of course, drug therapies are gonna be important and that's gonna be dictated by the conditions we're dealing with. So for hyperthyroid cases, we'd be using carbimazole or methimazole. For chronic kidney disease cases, we may be using things like benazapril or, or other drugs, OK?

Depending on what it is, if you've got, inflammatory bowel disease or chronic enteropathy, you might be using steroids. If you've got low grade alimentary lymphoma, it might be prednisolone and chlorambusil, for example. So all of these drugs we need to use both for the benefit of treating the disease.

But bear in mind too, they do have some side effects and we need to take those into account. Added to that, if appetite is a problem, then there may be some drug therapies we can use to intervene there to help. And then finally, when we get crisis, which we will have from time to time, then it might be pertinent to do some active nutritional support, placing a feeding tube.

OK. Again, different cases will dictate different needs. And what I want to do is illustrate all of this.

Basically using a single case that had pretty much everything. This is muffin, as you can see, an absolutely beautiful cat. When I first dealt with muffin, I actually knew muffins since she was a kitten, but the first time I had medical dealings, was from just over 9 years of age.

OK, so she's kind of early senior ages, you'd understand. I'm not going to go through everything that happened in a blow by blow account because that would be very boring. But this actually just shows you the timeline of a of just over 5 years when I was helping to manage her, OK, with various key points along the way as highlighted.

OK. Now, within this. What you can see is that she had two chronic diseases to contend with.

So she was initially diagnosed with chronic kidney disease in 2012, and latterly also deve developed hyperthyroidism from 2016. So we juggled those two diseases. Notice also that she presented as an emergency at different points.

And this will happen from time to time, these cases will have crisis, particularly if it's kidney disease or diabetes or a disease like that. Notice also how frequently appetite and food-related signs were present. Variable appetite, refusing food, poor appetite, but also things like nausea and vomiting will impact on it.

And remember, if we want to maintain weight, this is something we need to be addressing. OK. And notice also, we use various drugs both to stimulate appetite and of course, treat primary diseases such as carbibazole for hyperthyroidism.

We used various nutritional strategies from a low phosphorous diet for kidneys, an esophageal feeding tube, a nasal esophageal tube, and actually just normal food as well. So her plan changed across the way, and you will see this as time goes on. So this was, her sort of two years into diagnosis, where she's looking pretty good.

In 2016, about the time when hyperthyroidism developed, she'd noticed that she's, lost quite a bit of weight in that time, and this was towards the end stage, sadly, where we had to place a nasal esophageal tube. OK, so I'm not gonna go through exactly what we did and why, but what I'd like to do is illustrate the evolution of her case using the metrics that we've talked about. Body weight, body condition score, and muscle condition score, and I think hopefully just eyeballing these and the numbers you can actually see these things do change over time, particularly weight gradually decreases over time.

Body condition score worsens and muscle condition score does, although there are some peaks and troughs along the way. These changes generally correspond to increasing severity of disease, so it's disease-related rather than necessarily just old age. So she moved from iris stage 2 to iris stage 3, and of course developed hyperthyroidism along the way.

OK. Right, so kind of quite a lot here, . But notice actually, whilst there's been, there's always a gradual drag downward trend and you will see this in cases of chronic disease.

There are little upticks. So here, there's a sort of stabilisation here, an uptick here and here. So that does suggest that we can have some success with appropriate intervention.

OK. The first intervention was actually when she was first diagnosed with chronic kidney disease. She had to be hospitalised, she had hypokalemia, and so we needed to use fluid therapy and we placed an esophageal tube for a while.

And you can actually see that her weight increased quite dramatically as a result of that. And she sort of stabilised. OK.

Now, actually, I've talked about regular weight checks. This of course is looking back at case, and we didn't do a brilliant job here, if I'm being honest. There's this long period here, and this long period here where we didn't actually get regular checks, and you'll notice that we'd kind of let the ball.

Dropped basically in this time. So we realised actually there was a problem, and her kidney disease is kind of worsened, and so, and she stopped eating. She'd been on a low phosphorus diet in that time.

So we initially started with mirtazapine. And that actually did stabilise her for a bit, so she ate a little bit more, you can see her weight stabilised, but then it continued to decline despite appetite stimulants. So at this point, we actually compromised on her food, rather than the low phosphorusous diet on its own, the owner had to gradually introduce normal food, and by the end, it was mainly normal food and then anything that, the muffin would eat.

But note actually, despite that not being a perfect food, her weight did actually at least improve over time. Before declining. And it was at this point here that we spotted she had hyperthyroidism, and had I done a better job, I think I would have picked it up sooner because the likelihood is, as that Peterson study suggested, she would have had some sort of issues earlier on.

OK. The final rally here came when we introduced carbimazole, so drug therapy can lead to improvements in weight just like feeding can. And again, she had a further period of reasonably good quality of life before that final deterioration with her stage 3 kidney disease had worsened.

And despite nasal tube feeding, that wasn't successful so that's when we decided to have her euthanased. Hopefully that, I think illustrates a kind of the way we need to work with these underweight cases. You need to know the diseases, you need to be proactive in looking for them better than I think I did in that particular case.

And of course you need to adjust your therapies as you go. Finally, I just want to deal with the category of a cat that is in its senior years and is overweight. And I have to say this is actually a group that seems to be becoming more prevalent, as well as our weight management clinic at, Liverpool, we also have a, a, a senior cat.

Clinic as well, where we're kind of monitoring progress of cats and I can't remember the number, but I think it's about 20 to 30% of our cats in their senior years are actually overweight rather than underweight. And of course that can have an impact, and we do need to think about monitoring these as well. Our priorities obviously for this group are different from underweight cats and ideal weight cats.

Of course we do the same thing first. We need to recognise, treat and manage any chronic disease as we would normally do. That's a given.

But of course, if, if that's OK, then we need to be thinking about is it sensible to, to go for some modest weight loss, perhaps a partial weight loss plan as we talked about in, in the first lecture, to bring them towards the healthy weight. There may be medical reasons why that's a good idea. But of course at the same time, we don't want them to lose lean tissue.

So that's partly why a small amount of weight loss is necessary, so we don't get into the realms of, of lean tissue loss, which could have negative consequences on long-term health. So that basically means compromising with that target as we discussed in the first talk to ensure that we kind of get a little bit of weight off to improve their health, but not too much. And if you remember in that first talk, we talked a little bit about changing fat and lean mass with weight loss.

And based on studies we've done at, at, at, at Liverpool, where we've looked at body composition change, as I said in the first talk, 83% of what's lost is fat and about 17% is lean, but that is variable, and the big thing it relates to is how much weight the cat is losing overall. So for these individuals in the senior years, it's very much a sort of 10 to 15% range of weight loss where hopefully lean tissue loss is pretty neutral. I mentioned all of that in the first talk, so I won't dwell on that.

So, the other thing, of course, to emphasise is if we, if we don't have body composition, we could potentially just go on where body weight should end up. And if you remember from the Lisa Freeman work that I showed earlier, a body weight around about sort of 6 kg, give or take, is about the right amount to be, which will correlate probably with a condition score of 6 out of 9 and 5 out of 9 as an alternative. OK.

So I just want to sort of finish up by coming back to Sullivan. If you remember, Sullivan was an overweight cat that had multiple comorbidities, arthritis and diabetes, and chronic kidney disease. These two, arthritis and diabetes, were, were basically would be justifications for him to lose a little bit of weight from his 8 out of 9.

Because they should improve with weight loss. This one is a pause for thought, because, of course, losing too much weight may be counterintuitive. So that was the reason, as I mentioned in the first talk, that we chose a partial weight loss plan where he aimed at sort of 10 to 15%.

So we set his target weight in that range of sort of 6.5 to 6.9 kg.

Now the question that I didn't deal with that or the the thing I didn't deal with is what diet should we use for Sullivan in this situation? And the problem here we've got is that we've got different diseases that are telling us different things. For obesity, the best diets are high protein diets, because high protein diets minimise lean tissue loss.

But of course, I protein diets may not be the best for chronic kidney disease. OK. Why is that?

Well, if you look at diets, essentially, the amount of protein in the diet correlates with how much phosphorus is in the, in the diet. A lot of the phosphorus comes from animal sources or the same sources as protein. So it's not possible really to have a diet which is very high in protein, but not high in phosphorus.

OK. So you could argue, well, he's got chronic kidney disease. And if you look at iris, they recommend low phosphorus intake.

In fact, the reason we use the diets is to minimise phosphorus intake. The trouble is, if we go for a low phosphorus diet down here, that's a very low protein intake, and he's gonna lose lean tissue, so his weight loss is gonna be counterproductive. But conversely, if we go for a high protein weight loss diet, won't we be feeding too much phosphorus?

So, what is the question, what is the best diet? Now, I would actually say of these two, in the short term, for weight loss, I would prioritise. High protein, weight loss diet over low protein, kidney diet.

Now I appreciate that might be somewhat heretical to people who have an interest in nephrology. I'm gonna go for a high protein, high phosphorus diet here. And the concern people would rightly have is, won't this cat end up having too much phosphorus?

And won't that therefore make the kidney disease worse, because we've been told that high phosphorus is one of the things that speeds up kidney failure. Well, I want to just reassure you by telling you that actually, despite the choice of a high protein weight loss diet, I can promise you this cat will not consume too much phosphorus. And I'm gonna game this out with some numbers.

OK, so let's take this cat, 5.92 kg is his ideal weight. And we could say at this stage is Irish stage 2, he doesn't need a a a therapeutic diet, but he'd need a senior diet.

We can either feed him a senior diet or we can feed a weight loss diet. And just for the sake of, examples, we've got a senior consult stage one diet and satiety, which is a weight loss diet. If you look at the amount of phosphorus in these two diets.

The senod has 0.8% phosphorus aphed. The weight loss diet has 1.2%.

So if you work it out on a calorie basis per calories, there's almost twice as much phosphorus in the weight loss diet. Not a good start, OK. However, of course, the purpose of a weight loss diet is to feed it for weight loss.

So we're gonna feed fewer calories, less energy. Whereas for a senior dart, we wouldn't, I wouldn't recommend weight loss here because it's not designed for that. We'd be feeding this at maintenance.

So if we say, well, for maintenance, a cat's ideal weight needs 329 kalate, take my word for I've worked it out. For weight loss, this cat would need 188 Kcal per day. If you work out the actual amount of phosphorus per day based on the contents in the diet.

You can do the math yourself, or trust me, it, lo and behold means that we're feeding pretty much the same amount of phosphorus. So I guess the tame message here is for the weight loss phase, when we're trying to get this cat to lose 10 to 15%, feeding a high protein diet which has more phosphorus will not endanger this cat any more than feeding at a senior diet at maintenance. OK.

It still has the same amount of phosphorus. OK. Once of course you get to target, you then think about maybe switching to a senior or even an early, you know, early stage renal diet, depending on how the cat is.

So that's what we did for Sullivan. So he had a partial weight loss plan, and he lost weight from 7.7 to 6.7 kg, so he lost 13% in total, and we switched him to a senior diet at that point.

And then just monitored them as we would in for that second category of, of case. And it was a good news story. There was no evidence of any progression of his renal disease.

If anything, his renal param improved during weight loss because he took bloods regularly, and we had, we've had at least 36, actually slightly more follow-ups since then, and things have been, hunky dory for that time. So I hope this has been interesting. I hope again it's introduced some useful concepts of how to manage cases, and I just want to summarise some of the key points for you.

Remember The concept of health span, OK, and remember a healthy weight is the one where muscle mass is optimal. And adipose tissue is not excessive. OK, so that's what we would define as a healthy weight.

And I can't prove this, but I can be pretty sure logically that those cats at the healthy weight are gonna have the longest health span of all. And when, what that means clinically is a body condition score of between 5 and 6 out of 9, and ideally a muscle condition score of A, although for ceni cats we'd probably compromise at B, I, I'd, I'd take B at a starting point. During monitoring, obviously maintaining lean tissue is probably the big thing that that affects outcome.

So make sure you keep, keep an eye on that. Maintain the weight, but keep doing muscle conditions for as well, to keep an eye on that. And of course, to whether they're underweight, overweight or ideal weight to begin with, our main aim is either to keep them at the healthy weight range or move them towards that range a little bit.

And that hopefully is the best strategy for success. Thank you very much. Lovely.

Thank you, Alex. We've got a couple of questions actually. I think one of them possibly we could do now, if that's OK, which is, do we need to revisit the printed 9-point body condition score to show a healthy weight for a cat at a 5 or 6 rather than a 4 to 5, please?

I think we're probably talking semantic there, we could do. There is a concern about that that I would have, and well, and, and, and, and there's a wider concern, but one of the concerns is that, of course, when we talked about it, if, I talked about 5 or 5 out of 9 being best for prevention of disease, and 6 out of 9 being best for lifespan, arguably really the 6 out of 9 is probably only for senior cats, OK. And if we, if the message automatically is, you, we should be promoting 6 out of 9 healthy from the word go, then I think actually that's probably going to give the wrong message.

And part of the reason for that is if you look at weight trajectory over life, as currently, cats don't stay stable over life, they gain weight over life. So if we were to start them at a year 1 at 6 out of 9, by the year 9, they may be 8 or 8 or 9 out of 9. So I think the problem with doing that is the psychological message, OK.

The other thing about that is the disease is probably something, you know, if you want to prevent diseases from happening, that's what we want to target early on. So I'd probably start definitely by aiming at a 5 and a 9 early on to prevent that disease and only worry about lifespan in the senior phase. We do such a bad job already, number one, of condition scoring at all.

I think talking about changing the, what looks in, in the condition score is not going to be helpful. And added to that, we, people literally very rarely care about getting their patients to lose weight already. And if, if, if automatic was saying 6 hour 9 you don't worry about full stop, where there could be reasons why that might need to be the case because of disease, again, I think changing that would, would, would paint the wrong message.

Sure, thank you. There's another question from Jennifer, and this might be something I think we'll, we'll take on afterwards. What, what defines a senior diet?

Are there standards that have been set by anyone at this time? But I, I, I think we've probably, there's quite a lot to answer there. I, I can give a brief a very brief answer to that.

So there isn't a, a, a different companies may differ in what they would use, but there are some. There, there are schemes which do look at essential neutral requirements at different stages of life. So if you look at NRC 2006 and the guidelines, there are some differences.

There's less information about senior cats in fairness, but, but from various studies, these things have been, the, the, the, the, you know, the, the companies do look at what the priorities are. So some companies obviously would focus on things like, cognitive decline and cognitive, Impairment. Others will look at maintaining weight, and preventing unnecessary weight gain.

Often, if technically, you need two different ones. You need ones for patients that don't eat well, then they need to be higher energy, and you need those for the majority that kind of overweight, the, the, the less. So that, there are things there, but there are a set that is, was there are some guidelines as to what nutrient requirements are in different stages of life, it's, it, there's not a single set of guidelines that everybody would use.

Lovely, thank you. And one final question, we might have a minute or so. Dogs with CKD and a body condition score of 9+, would you suggest the weight loss food short term like the cats or different?

We, we do, we do that for both dogs and cats, and, and, in many respects, things are similar, I think, in, in terms of that trajectory of, of weight loss. So, so if it's kind of 6 out of 9 for, for a dog again, I probably wouldn't worry too much, even though if you look at the, the studies, actually 4 to 5 out of 9 is better for a, for. Cat for life, for a dog for a lifespan.

But I, I, I, we probably do apply the same tools. And again, it's based on a, you know, the overall benefits. So a 9 out of 9 almost certainly is going to have problems with mobility and quality of life, and so on and so forth.

So, yeah, I think almost certainly I would, I would aim for that.