It's not just people who get sick from stress. A recent Ohio State University study found that healthy cats show signs of illness when stressed.
At the same time, cats diagnosed with feline interstitial cystitis (FIC) became healthier when stress levels were reduced, the study showed.
Twelve of 32 cats in the three-year study were healthy and 20 had FIC, a chronic pain syndrome that affects the cat's bladder.
Lower urinary tract diseases occur in about 1.5% of house cats, the researchers said, and a lot of pet owners can't stand the messes that come with it, so millions of sick cats are euthanised or turned over to shelters every year.
The owners of the sick cats at OSU had all decided to have their pets euthanised, but agreed to let them take part in the study first.
Doctoral candidate Judi Stella; Tony Buffington, a professor of veterinary clinical sciences; and Linda Lord, an assistant professor in the school's Department of Veterinary Preventive Medicine, observed the colony of neutered and spayed cats at the university's research lab.
Stella spent the first part of the study trying to make every aspect of each cat's life the same - their cages, litter boxes, food, music, toys, time spent with the other cats and time spent with her and a caretaker.
"I had to be careful if I was having a bad day," she said, so it didn't rub off on the cats.
"This study shows that an enriched environment - one that includes hiding areas, toys, bedding and other physical features, plus an everyday routine including a consistent caregiver, feeding and play times -reduces or altogether prevents some common signs of feline sickness such as decreased appetite, vomiting or eliminating outside of their litter boxes.
"The significance is that minimising stress can decrease illness," said veterinarian and feline expert Jane Brunt, a member of the CATalyst Council, Inc. in Timonium, Maryland, and owner of Cat Hospital at Towson for over 20 years.
The study, funded by the National Institutes of Health, was published in the Journal of the American Veterinary Medical Association.
Human diseases similar to interstitial cystitis include irritable bowel syndrome and fibromyalgia, said Buffington, who also works with stress researchers at the University of California at Los Angeles' Centre for Neurobiology of Stress.
Stress to a cat might be nothing more than unwanted attention, a dirty litter box or a strange noise, Stella said.
Stress free time
During stress-free times, both healthy and affected cats got sick less than once a week.
During weeks when routines were altered, causing stress, the healthy cats got sick about 1.9 times a week and the others twice a week, nearly tripling the risk for sickness in all the cats. Levels returned to normal when the stress passed, Buffington said.
For now, the researchers hope cat owners and vets will look at a sick cat's environment before opting for euthanasia.
"Cats are not a pack species. They are not used to living in large groups. Their two primary predators are larger carnivores and primates and so who do they live with? Dogs and people. It can be tough being a cat," Buffington said.
Research conducted by Buffington in 2006 found similar health improvements when cat owners enriched home environments for their pets.
"Cat owners can be educated about managing and maintaining an enriched environment," Brunt said. "Several parallel human studies are corroborated by this and other feline studies, indicating that stress and disease are linked." (Sapa/ January 2011)
Diseases from cats
Cats may up eczema risk
Common cat health myths debunked