Behavior Problems of Older Pets
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It is not unusual for behavior problems to develop in older pets. Many of the problems have similar causes to those in younger pets. Changes in the household, changes in the environment and new stressors can lead to problems regardless of age. For instance moving, a change in work schedule, a family member leaving the home, or new additions to the family such as a spouse or baby, can have a dramatic impact on the pet's behavior.

Unfortunately our older pets are also likely to develop an increasing number of medical and degenerative problems as they age. Any of the organ systems can be affected and play a role in the development of a wide variety of behavior problems. For example, diseases of the urinary system and kidneys can lead to house-soiling. Diseases of the endocrine organs such as the thyroid gland and pituitary gland can lead to a variety of behavioral and personality changes. A decline in the senses (hearing and sight), painful conditions, and those that affect mobility may cause the pet to be more irritable or more fearful of approach and handling (see handout on Behavior - causes and diagnosis of problems for more details). Aging pets may develop many of the same changes as are seen in Alzheimer's disease in people.

How can I tell if my pet's behavior problem is age related?
Regardless of age, every behavior case must begin with a complete veterinary physical examination and a clinical and behavioral history. In addition, blood tests and a urinalysis may be needed to rule out organ disease and endocrine imbalances. Sometimes a more in depth examination of a particular organ system may be indicated. Additional laboratory tests, radiographs, ultrasound, spinal tests, brain scans, or perhaps a referral to a specialist may all be appropriate depending on the initial findings.

My pet is quite old. Is there any point in doing these tests? What can be done?
Unfortunately many pet owners do not even discuss behavior changes with their veterinarians since they feel that they are a normal part of aging and perhaps nothing can be done for the dog. This is far from the truth. Many problems have an underlying medical cause that can be treated or controlled with drugs, diet or perhaps surgery. Hormonal changes associated with an underactive or overactive thyroid gland, diabetes, diseases of the pituitary gland and testicular tumors can all lead to dramatic changes in the pet's behavior and many of these problems can be treated or controlled. Degenerative organ systems can often be aided with nutritional supplementation or dietary changes. High blood pressure, cardiac disease and respiratory diseases may be treatable with medication, which may dramatically improve the quality and even length of the pet's life. And new drugs are now available that are useful in the treatment of age related cognitive dysfunction.

What are some things to look out for? Changes in behavior (see answer on cognitive dysfunction below), an increase or decrease in appetite or drinking, an increased frequency or amount of urination, loss of urine control (dribbling urine, bedwetting), changes in stool consistency or frequency, skin and hair coat changes, lumps and bumps, mouth odor or bleeding gums, stiffness or soreness, excessive panting, coughing, changes in weight (increase or decrease), and tremors or shaking are some of the more common signs that should be reported, should they develop in your pet.

What is cognitive dysfunction and how is it diagnosed?
It is generally believed that, as in people, a dog's (learning, memory, mental alertness) ability tends to decline (dysfunction) with age. This may also be true for cats. If your dog has one or more of the following behavior changes and all potential physical or medical causes have been ruled out, it may be due to cognitive dysfunction:

a) Decreased reaction to stimuli (i.e. sounds, sights, odors)
b) Confusion, disorientation, weakness
c) Decreased interaction with the owners (e.g. less affectionate)
d) Increased irritability
e) Irregular sleep-wake cycles (sleeping days, waking more at nights)
f) Increased vocalization
g) House-soiling or loss of other previously learned behaviors
h) Decreased ability to recognize commands, people, places or other animals
i) Decreased interest in food
j) Circling, repetitive and compulsive disorders
k) Decreased tolerance to being left alone

In one study of dogs that were 11-16 years of age, owners specifically questioned regarding signs of cognitive dysfunction reported that 62% of their pets exhibited at least one of the signs above.

Do pets get Alzheimer's?
Many of the same changes and lesions associated with Alzheimer's disease in people have also been recognized in dogs and cats. Should multiple behavior problems develop and these changes progress to the point where the dog or cat is no longer a "functional" pet, the condition may be consistent with senility or dementia of the Alzheimer's type.

Can geriatric behavior problems be treated?
In many cases the answer is yes. Of course if there are medical problems contributing to the behavior changes, the problem may not be treatable. The key therefore is to report changes and bring in your pet for assessment as soon as new problems arise.

In cognitive dysfunction, depletion of brain dopamine levels, may be responsible for many of the behavior changes. New drugs are available that can successfully treat some forms of cognitive dysfunction in dogs. These drugs help to normalize the brain dopamine levels, help to protect against nerve cell deterioration and have few side-effects. Many of the behavior problems listed above will show marked improvement and overall these dogs may become more attentive, playful and affectionate. It is important to note however that once new habits are learned, retraining and changes to the environment may also be needed to resolve the problem. For example, in addition to drug therapy, dogs that have begun to eliminate indoors will need to be retrained much like a puppy that has begun to eliminate indoors.

Dogs that develop behavior problems due to underlying medical conditions may need alterations in their schedule or environment in order to deal with these problems. If the condition is treatable and can be controlled or resolved (e.g. Cushing's disease, infections, painful conditions) then, as discussed, you must be prepared to retrain the dog, since the new habit may persist. For example, the house-soiling pet may have less duration of control due to its medical problems. If these conditions cannot be controlled, then the pet's schedule (more frequent trips outdoors) or environment (installing a dog door, paper training) may have to be modified. With conditions that affect a cat's mobility, adjustments may be needed to the pet's environment, litter box placement, or type of litter box, (e.g. a lower sided box).

Please consult your veterinarian regarding any persistent medical or sudden behavior changes in your pet.

If you would like further assistance with this, or another pet behavior topic, please contact our Behavior Helpline at (314) 951-1540 or e-mail behavior.desk@hsmo.org.
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