Definite personality changes and behavioral problems can be extremely challenging to the practitioner and extremely frustrating
to the client. Some problems are mild and acceptable, while others are major concerns initiating euthanasia discussions. General
behavioral changes are elderly patient's desire more attention, are more jealous, are more irritable, are less mentally alert,
and have altered sleep cycles.
According to an AAHA sponsored study, 60% of dogs and cats sleep in the owner's bed or in their bedroom. As a result, any
sleep cycle disturbance poses an inconvenience for both the pet and the owner(s). Altered sleep patterns are common geriatric
"behavioral" dilemmas especially in those situations where the owner is affected. For those pets that sleep in a dog house
or garage, the owners would be unaware of a problem.
With sleep cycle disturbances, the owners report one or more of the following complaints; night crying (cats); routine nightly
pacing of the bed room or entire house; periods of panting as if they were anxious or hot; they awaking the owners to go outside
for no obvious reason; the pet seems to be unable to get comfortable as they are either up and down or constantly "fluffing
up" their bed. Various causes of sleep cycle disturbances have been postulated include; an underling painful condition such
as dental disease, osteoarthritis, spondylosis or a chronic IVD; sleeping on a hard surface; an altered biological clock where
the patient sleeps all day then can't get to sleep at night; the patient is cold from either poor circulation or a lowered
basal metabolic rate associated thermoregulation issue; or a simple phobia of the dark associated with decreased night vision.
In some cases, a sleep cycle complaint can also be a manifestation of Cognitive Dysfunction Syndrome in dogs and cats. The
author would advocate any or all of the following options; a warm soft bed; a night light; a radio playing softly; a brief
10 minute walk before bedtime; hydroxyzine 1-3 mg/kg (to effect) prior to bedtime; melatonin 1-3 mg / dog PO SID; and/or a
1 week trial of a short term pain management program to rule out a "painful" condition.
Many of these common "old dog or old cat" behaviors are often grouped into a syndrome called Cognitive Dysfunction Syndrome
(CDS). CDS is a progressive disease syndrome of older dogs and cats associated with various brain pathology and /or neuro-transmitter
imbalances that results in commonly recognized groups of related behavioral changes. Impairments in memory, learning, perception
and/or awareness are common findings of CDS. These clinical behaviors in older patients are related to impaired mental function
often referred to as senility, dementia, or canine / feline Alzheimer's disease". CDS is a progressive disease of the brain
seen in a high percentage of older dogs and cats and is associated with persistent changes in behavior.
What is actual incidence of CDS in older dogs and cats? In one recent study, 75% of owners of dogs that were over 7 years
of age, reported at least one symptom consistent with CDS, however only 7% had reported it to their veterinarian, thinking
the observed behavior was "normal" part of aging. While the incidence of CDS in cats is also unknown, there is growing evidence
that it is actually much more common than previously thought although the onset occurs later in life. In a recent study of
feline CDS, when carefully questioned, 50% of owners of cats over 12 years of age reported at least one symptom compatible
with CDS, but less than 1% had reported it to their veterinarian. In addition there are some significant differences in the
age of onset and symptoms in cats compared to dogs; the older age of onset in cats; the cat owners lack of recognition/interpretation
of the specific clinical signs of CDS. These two factors combine with less frequent veterinary visits of cats, all contribute
to the lack of CDS clinical knowledge.
All of the causes on CDS in dogs or cats have not been identified or proven. Much of what is known comes from extrapolating
the research done in humans, primates, and rats. Some of our current knowledge has come from research and some from the perceived
clinical benefits observed in various clinical trials or clinical experiences.