As discussed in Part One of this article (Warnes, 2015), behaviour changes in elderly cats and dogs can indicate the presence of a number of different medical problems as well as the development of age-related cognitive dysfunction. This article will discuss management strategies that can improve the quality of life for elderly animals with mobility problems including conditions associated with chronic pain, sensory deficits and cognitive dysfunction. The various treatment strategies for animals with cognitive dysfunction will be outlined, as well as preventive strategies that may reduce the rate of cognitive decline and delay onset of cognitive dysfunction.
Environmental management strategies to improve accessibility
Elderly animals need to be able to move around their environment and access important resources easily. This can be particularly challenging for animals with medical problems affecting their mobility, including conditions associated with chronic pain such as degenerative joint disease or spinal problems, reduced sensory abilities or cognitive dysfunction, which can be associated with impaired spatial awareness and navigational ability (Gunn-Moore, 2011; Landsberg et al, 2012). Important resources include food, water, comfortable resting places, toilet locations and, for cats in particular, places to withdraw to or hide if they do not wish to interact with people or other animals in the home. Suggestions for improving access to the environment and individual resources are outlined in Table 1.
| Resource | Suggestions for improving environment and increasing accessability for elderly animals | |
|---|---|---|
| Dogs | Cats | |
| Food and water | Raising bowls off the ground will help dogs with joint and spinal problems to eat and drink more comfortably Non-slip matting underfoot will prevent dog slipping when eating or drinking | Need to be in separate locations |
| Toileting areas | Dogs with mobility problems may need to learn to use a toileting area closer to the house, or even be provided with a toileting area indoors, e.g. by placing puppy pads in a large tray |
Needs to be separate from feeding and drinking locations Cats with mobility problems will prefer large, low sided litter trays, or equivalents such as gardeners' potting trays Finer-grained litters are easier to stand on and dig than coarser litters |
| Sleeping areas and beds | Beds should be comfortable and supportive, e.g. memory foam, easy for animal to get into and out of, and large enough for them to lie out flat if they wish |
Beds should be comfortable and padded, easy for animal to get into and out of, and large enough for them to lie out flat if they wish |
| Moving around inside and outside home | Non-slip matting or carpet in locations of important resources and on the walkways between important areas can improve accessibility for elderly animals with mobility problems Non-slip ramps can help dogs navigate steep steps outside the home and also get into and out of cars (Figure 1) Specially designed harnesses can be helpful for supporting dogs with mobility problems to enable exercise and access to toilet areas | Non-slip matting or carpet in locations of important resources and on the walkways between important areas can improve accessibility for elderly animals with mobility problems |
Due to cats' natural preference for separate food, water and toilet areas it is important to space these resources out carefully while ensuring they are all easily accessible from the cat's resting area (Gunn-Moore, 2011). If a cat spends time on different floors in the home it is sensible to locate a full set of resources, including a litter tray, on each floor. Once resources have been located appropriately they should always be kept in the same places so animals can find them easily.
If there are other animals in the home it will be necessary to ensure there is no competition for resources, and this may involve using barriers to restrict which areas of the home individual animals have access to, either permanently or at particular times for example when animals are feeding and resting.
Treatment strategies for animals with cognitive dysfunction
Dietary supplementation
Studies suggest that diets supplemented with a variety of antioxidants including vitamins C and E and other neurosupportive and protective factors including phosphatidylserine, L-carnitine, omega-3 fatty acids and B vitamins can reverse some of the behavioural changes associated with cognitive dysfunction in dogs (Milgram et al, 2004; Heath et al, 2007; Osella et al, 2008). They are likely to have similar effects in cats although this has not been studied (Gunn-Moore, 2014). In addition to reducing oxidative damage, these compounds may help to promote the formation of new neural pathways and new learning, especially if used alongside strategies for environmental enrichment and mental stimulation (Milgram et al, 2004; Fahnestock, 2012).
Various other supplements may also have beneficial effects on cognitive function. Medium chain fatty acids, as found in coconut oil, may provide an alternative energy source for damaged brain cells that can no longer metabolise glucose effectively (Pan et al, 2010; Landsberg et al, 2012). However diets containing medium chain fatty acids are not very palatable for cats (Gunn-Moore, 2014). S-adenosyl-L-methionine (SAMe) plays an important role in the formation of proteins including hormones and neurotransmitters and supplementation can improve cognitive function in elderly cats and dogs showing early signs of cognitive decline (Araujo et al, 2012).
Most commercially available diets for elderly cats and dogs are now supplemented with antioxidants and omega-3 fatty acids. In addition there are several diets and supplements marketed specifically for elderly animals showing signs of cognitive dysfunction (Table 2).
| Diet or supplement | Active ingredients | Comments |
|---|---|---|
| Hills b/d | Flavonoids and carotenoids from fruits and vegetables, vitamin E, vitamin C, beta-carotene, selenium, L-carnitine, alphalipoicacid, omega 3 fatty acids | Not suitable for cats because alpha lipoic acid is toxic |
| Purina Proplan Senior 7+ for Dogs | Medium chain fatty acids | Dogs only |
| Aktivait (VetPlus) | Phosphatidylserine, omega-3 fatty acids, vitamins E and C, L-carnitine, alpha-lipoic acid, coenzyme Q, selenium | Dogs only due to alpha lipoic acid |
| Aktivait Cat (VetPlus) | Phosphatidylserine, omega-3 fatty acids, vitamins E and C, N-acetyl cysteine, L-carnitine, coenzyme Q10, selenium | Cats |
| Senilife (CEVA) | Phosphatidylserine, pyridoxine (Vitamin B6), ginko biloba extract, resveratrol d-alpha-tocopherol | Dogs and cats |
| Novifit/NoviSAMe (Virbac USA and Canada) | S-Adenosyl-L-methioninetosylatedisulfate (SAMe) | Dogs and cats Not readily available in UK |
| Hepatosyl plus (CEVA UK) | S-Adenosyl-L-methionine-tosylate disulfate (SAMe), Vitamin E, silybin (milk thistle extract, also has antioxidant effect) | Dogs and cats Marketed in UK for liver support but may also improve cognitive function |
Increasing mental stimulation and physical activity
Animals in the early stages of cognitive decline will usually benefit from increasing mental stimulation and physical activity. This can significantly improve their demeanour and may also delay progression of clinical signs (Landsberg et al, 2012). However animals that are highly anxious and those with more severe cognitive dysfunction may find changes to their routine and environment extremely stressful (see below).
Activity feeding
Food can be given in ways that encourage animals to show a variety of hunting behaviours including searching and manipulation with mouth and paws and also to encourage problem solving. There are a wide variety of commercially-available food dispensers and puzzle feeders available for both cats and dogs. It is also possible for owners to make activity feeders very cheaply using cardboard boxes, egg boxes or toilet roll middles, or even just to scatter food on the floor or grass to encourage animals to search for it (Ellis, 2009; Landsberg et al, 2012). It is useful to have a variety of different bought and home-made activity and puzzle feeders in the surgery to show owners and demonstrate how they work. When introducing activity feeding to elderly animals, particularly those with cognitive decline, it is important to start with activities that are easy, taking into account the animal's natural abilities and any health-related issues they may have. The difficulty should only be increased if the animal can cope with this without becoming distressed or frustrated.
Social interactions
Elderly animals with cognitive dysfunction will often not seek out interaction with humans and may spend much of the day asleep. In addition to the general lack of mental stimulation this can also increase the likelihood of animals being awake at night. Owners need to be aware that they may have to initiate most or all interactions with elderly animals although it is important to ensure these interactions are not stressful for the animal.
Relationships between animals that have previously got on well can sometimes break down when one animal develops age-related health problems or cognitive dysfunction (Cory, 2013; Landsberg et al, 2013). Management strategies may need to be introduced to ensure there is no competition for resources and that animals can be separated at potential problem times, when owners are unable to supervise them or permanently if necessary.
Introducing a new pet into the household can be extremely stressful for an older animal with cognitive dysfunction, and owners would be better advised not to do this, especially with cats and any dog that does not have good social skills or is showing severe cognitive dysfunction. However some elderly dogs without severe cognitive dysfunction can benefit from the introduction of a younger dog into the household, especially if they have good social skills and the introduction is performed very carefully (Landsberg et al, 2013).
Play
Encouraging animals to play can significantly improve their demeanour. Play can be associated with a positive emotional response and increasing aerobic activity will also boost circulation, increasing oxygen supply to the brain. Just as for activity feeding, games will need to be tailored to the individual animal bearing in mind any health problems, including sensory deficits, they may have. Low-impact games such as gentle throw-and fetch or search games are appropriate for most elderly dogs, and for dogs with vision loss, search games to find food or toys are particularly suitable. Short play sessions with fishing rod toys or toys that roll and/or make sounds will suit most cats. Older dogs and cats often get bored of toys quite quickly so rotating toys every few days can help them remain interesting.
Exercise and exploration
Many elderly dogs that can no longer walk far will benefit from shorter walks with the opportunity to sniff and explore new places. Dogs with mobility problems can be taken out in the car and then given a short walk in a new location, or accompany owners on longer walks by riding in a modified baby buggy.
Unfortunately cats with cognitive dysfunction often become disorientated and may get lost even close to home. They are also at increased risk of injury, for example through road traffic accidents, as are cats with mobility problems and sensory loss. Some elderly cats prefer to remain indoors, but if cats do want to go outside they can do this more safely if the cat will wear a harness, or possibly by fencing the garden to prevent the resident cat leaving and other cats entering (see Fencing in your Garden: http://icatcare.org/advice/fencing-your-garden).
Training
As long as dogs are not too cognitively challenged, reward-based training can be a good way of providing mental stimulation as well as retraining any lost previously-learned behaviours such as toileting outside. Using a marker to indicate when a behaviour will be rewarded, such as a clicker for dogs that can hear, or a light flash or hand signal, may make learning easier. Other simple behaviours such as targeting, where a dog is taught to touch an object or a person's hand with their nose, are fairly easy for dogs to learn and can be an enjoyable way for dogs and owners to interact.
Maintaining a constant environment
Animals with severe cognitive dysfunction can find changes in their routine and environment extremely stressful. Instead of attempting to increase mental and physical stimulation these animals will benefit more from attempts to maintain a constant routine and environment. Highly anxious animals, and especially cats, may cope best when restricted to a single room containing food, water, a litter tray, resting and hiding places. It is important to keep furniture and resources in the same places and to avoid big changes in the scent profile of the room, for example by not using strongly-scented cleaning products, as these can be very challenging for cats. It also helps to maintain a fairly consistent routine, ensuring that important events occur in the same order and at approximately the same times every day.
Medication for animals with cognitive dysfunction
Elderly animals may require medication to treat medical conditions such as osteoarthritis, hypertension, endocrine disorders etc. In addition, animals with cognitive dysfunction may be given medication for three main reasons: to improve cognitive function; to reduce anxiety; and to encourage them to sleep at night (Overall, 2013). The choice of whether or not to medicate and which drug to use will be determined by the veterinary surgeon based on the animal's general health and any other drugs they are taking, as well as the behavioural signs they are showing.
Medication to improve cognitive function
The two drugs licensed for use in dogs with cognitive dysfunction and available in the UK are selegiline and propentofylline (Table 3). Selegiline (Selgian, CEVA) increases the availability of dopamine by inhibiting its breakdown by monoamine oxidase B enzymes, has antioxidant effects and may reduce neuronal cell death (Ebadi et al, 2002). Propentofylline (Vivitonin, MSD; Vitofyllin, Animalcare) increases oxygenation of brain tissue through increasing cerebral blood flow and reducing microthrombus formation. Both drugs can improve alertness, general demeanour and cognitive function in dogs with cognitive dysfunction (Landsberg et al, 2012; Cory, 2013). Although unlicensed, both drugs have been used in cats and anecdotal reports suggest they can have similar beneficial effects to those seen in dogs (Gunn-Moore, 2014).
| Drug | Trade name(s) | Mode of action | Dose rate in dogs | Dose rate in cats |
|---|---|---|---|---|
| Selegiline | Selgian (CEVA) | Monoamine oxidase B inhibitor: increases dopamine availability; anti-oxidant and neuroprotective effects | 0.5–1 mg/kg q24h orally for a minimum of 2 months. Best given in morning | *unlicensed* Suggested doses 0.25–1.0 mg/kg q24h orally (Gunn-Moore, 2014) |
| Propentofylline | Vivitonin (MSD) Vitofyllin (Animalcare) | Increases cerebral blood flow and oxygenation | 2.5–5 mg/kg q12h orally. Administer 30 min prior to food. | *unlicensed* Suggested dose 12.5 mg/cat q24h orally (Gunn-Moore, 2014) |
Anxiety-reducing medication and supplements
Elderly animals with severe anxiety may benefit from medication with drugs that can reduce anxiety. The most commonly used are serotonin-increasing drugs including tricyclic antidepressants (TCAs) and specific serotonin reuptake inhibitors (SSRIs) (Landsberg et al, 2012). Unfortunately these drugs are not suitable for animals with certain health problems or those taking certain medications. They cannot be used in animals that are taking selegiline, and if swapping from a TCA or SSRi to selegiline or vice versa there should be at least a 2 week gap between finishing one and starting the other (Overall, 2013; Ramsay, 2014). Although also unlicensed, gabapentin can reduce anxiety in addition to its pain-reducing effects and is generally well tolerated even in elderly animals (Overall, 2013).
There are a few supplements that may have mild anxiety-reducing effects with less likelihood of causing unwanted side effects than anxiolytic medication. These include alpha casozepine (Zylkene, Vetoquinol) and various supplements containing L-tryptophan, L-theanine and B vitamins including KalmAid (Nutri-science), Calmex (VetPlus) and Adaptil tablets for dogs (CEVA). Royal Canin's Calm diet, available for cats and small dogs, contains alpha casozepine, L-tryptophan and B vitamins.
Sedative medications
One of the biggest problems for owners is being kept awake by elderly animals that become unsettled or distressed at night. Helping animals and therefore their owners to sleep at night can make a huge difference to an owner's quality of life and may even make the difference between an animal being euthanised or not. Addressing the underlying reason(s) for the animal being unsettled including treating pain and any other contributing medical conditions and implementing the treatment strategies for cognitive dysfunction outlined here will hopefully lead to animals settling and sleeping better at night. However in the short term it may also be necessary to use sedative agents to help animals settle at night until the other strategies become effective.
The classes of drugs most commonly used to encourage animals to sleep better at night are sedative antihistamines and longer-acting benzodiazepines (Table 4). Sedative antihistamines have a more non-specific sedative effect while benzodiazepines are more appropriate for animals that are not settling due to anxiety. The choice of drugs will also be influenced by an animal's health and any other medication they are on. Animals respond very variably to both antihistamines and benzodiazepines so owners will need to experiment to determine both the most appropriate dose (by starting at the lower end of the dose rate and increasing gradually if necessary) and when to give the medication before bedtime. Owners also need to know that both antihistamines and benzodiazepines can occasionally cause paradoxical excitement, and that benzodiazepines can potentially disinhibit aggression (Landsberg et al, 2013; Ramsay, 2014). Gabapentin can also have a mild sedative effect and may be particularly useful in elderly animals that are unsettled at night because they are uncomfortable as well as anxious (Landsberg et al, 2013).
| Drug | Trade name (s) | Class of drug | Dose rate in dogs for oral administration | Dose rate in cats for oral administration |
|---|---|---|---|---|
| Chlorphenamine | Piriton | Sedative antihistamine | 4–8 mg/dog as single dose before sleep | 2–4 mg/cat as single dose before sleep |
| Diphenhydramine | Dreemon, Nytol | Sedative antihistamine | 2–4 mg/kg as single dose before sleep | 2–4 mg/kg as single dose before sleep (can rarely cause paradoxical excitement) |
| Trimeprazine Tartrate | Vallergan | Sedative antihistamine | 0.5–2 mg/kg as single dose before sleep | N/A |
| Clonazepam | Klonopin |
Benzodiazepine | 0.1–0.5 mg/kg as single dose | 0.02–0.2 mg/kg as single dose |
| Lorazepam | Ativan |
Benzodiazepine | 0.02–0.05 mg/kg as single dose | 0.02–0.05 mg/kg as single dose |
| Gabapentin | Neurontin | GABA Analogue | 10–30 mg/kg q8–12 h | 3–10 mg/kg q12 h |
Preventive strategies to reduce cognitive decline and delay onset of cognitive dysfunction
Tests indicate that cats and dogs start to show evidence of cognitive decline several years before behaviours more typical of cognitive dysfunction become apparent (Landsberg et al, 2012). It is therefore logical to start some of the treatment strategies for cognitive dysfunction including increasing mental stimulation and dietary supplementation well before animals start to show obvious signs of cognitive dysfunction.
In humans cognitive reserve, or the brain's ability to function adequately despite increasing amounts of damage, appears to be influenced by a number of factors including the amount of mental and physical activity and positive social interaction people engage in throughout their lifetimes (Stern, 2006). It is therefore possible that keeping animals active both mentally and physically, and encouraging positive social interactions with people and other animals throughout their lifetimes may help reduce the rate of cognitive decline and likelihood of developing cognitive dysfunction. Other important strategies include helping animals to remain healthy through ensuring they are receiving good quality nutrition, preventing or treating diseases as they arise, particularly those that can directly influence brain function, and minimising stress because chronic stress is a risk factor for the development of cognitive dysfunction (Cory, 2013). Nurses are very well placed to discuss all these issues with pet owners whenever they come to the surgery, from puppy and kitten-hood onwards.
Conclusion
Veterinary nurses can significantly improve the welfare of elderly cats and dogs under their care in a number of ways. They can discuss with owners management strategies that can improve the quality of life particularly of elderly animals with mobility problems, sensory loss and cognitive dysfunction. They can also inform owners about the treatment options available for animals with cognitive dysfunction and help design treatment plans, including dietary supplementation and practical strategies for increasing mental stimulation and physical activity, that are appropriate for individual animals taking into account any other health or behavioural problems they may have. Finally they can advise owners about preventive strategies that can be implemented throughout the lifetime of their pets that may help increase cognitive reserve and slow the rate of cognitive decline as they age.