Complete Care for Your Aging Cat - Amy Shojai [124]
She examined 155 cats, aged eleven to twenty-one years old. She evaluated whether the cat’s relationship with the owner or other animals changed—perhaps a decrease in tolerance to being handled or being left alone, for example, or failure to recognize familiar people or places. “We asked if these cats were waking up the owner at night, or excessively vocalizing at night; if they’re wandering, pacing, or any type of repetitive or compulsive type behaviors; and we looked at anxiety, fear and irritations to see if cats seemed to be more irritable than when they were younger.” The last question covered memory and learning—if the cat still used the litter box, for example. “We definitely had a lot of cats that didn’t have any medical conditions [to account for] showing signs,” she says, with cats older than fifteen vocalizing a much more at night.
Melissa Bain, DVM, a lecturer at University of California-Davis also researched feline cognitive disorder. She began by conducting phone interviews to screen the owners of cats, aged eleven to nineteen that were patients at the UC-Davis Veterinary Medical Teaching Hospital. Basic questions were asked to identify and eliminate cats from the study that had physical causes for suspect behavior changes. They ended up with 130 cats for the study. These were then further identified as being positive or negative for a behavior change due to potential cognitive dysfunction in these four categories: disorientation, interaction with owner, housetraining, sleep-awake cycle. “We asked them three to four questions in each category. For disorientation, we asked if the cat got lost in the house or the yard, or stuck in corners or behind furniture, for example.” Owners were asked to answer with increase, decrease, the same, or absent. They were also asked to compare the aged cat’s behavior to when they were middle-aged at seven to eight years old.
“They were all spayed females and castrated males,” says Dr. Bain, “and the cat had to be positive for two or more signs in a category to be considered positive for that category. We haven’t done the statistics on it, but there doesn’t appear there’s any difference between the sexes.” She says many of the cats showed increased vocalizing for no reason. “We didn’t know what category to put it in. The cat would just meow and act confused. It seemed to happen at night.”
The acronym D.I.S.H. (disorientation, interaction, sleep changes, housebreaking) was created to help identify cognitive disorders in dogs, and because the drug Anipryl was licensed for use in those specific categories, says Dr. Landsberg. However, the acronym doesn’t account for anxiety or compulsive behaviors such as howling and repetitive pacing that tend to be quite common in both older dogs and older cats. “Broader categories are probably a bit better. That’s what we were looking for in cats, because you don’t look at learning and memory tests in exactly the same way,” he says.
Dr. Bain’s cat study indicated that 20 percent of eleven-to-twelve-year-old cats were positive for one or more categories. “We considered one category to be mild impairment,” says Dr. Bain. “Only 3 percent were positive for two or more categories—a very small amount.”
As the cat’s age increased, so did the prevalence. The percentage of thirteen-to-fourteen-year-olds positive for one or more categories was 33 percent, but only 8 percent were positive for more than two categories. 42 percent of the fifteen-to-sixteen-year-olds were positive for one or more categories; 16 percent of this group was positive for two or more categories. 61 percent of the final group of cats aged seventeen-to-nineteen-year-old cats were positive for one or more categories. “43 percent were positive for two or more,” says Dr. Bain.
Age-Defying