Effects of Cushing’s Disease – From the Cat’s Point of View
Cushing’s disease, also known as hyperadrenocorticism, fortunately is not very common in companion cats. When it does occur, affected cats have many of the same symptoms as dogs with Cushing’s disease. However, there are some very important differences in how this condition affects dogs and cats. Feline Cushing’s is a disease of middle-aged and older, primarily mixed-breed cats of either gender, although females seem particularly predisposed. Unlike Cushing’s disease in dogs, this disease in cats is strongly associated with diabetes mellitus. Affected cats tend to become extremely thirsty, drink a lot of water and urinate much more than usual. They often become tired, weak and lethargic.
Symptoms of Cushing’s Disease in Cats – What the Owner Sees
Owners of cats with Cushing’s disease may notice one or more of the following signs in their pets:
- Increased thirst and water intake (polydipsia)
- Increased urine output (polyuria)
- Increased frequency of urinating
- Increased appetite and food intake (polyphasia)
These signs are often caused by diabetes mellitus, which is present in about 75 percent of cats that have Cushing’s disease. Other signs during the early course of Cushing’s disease are often more subtle, general and non-diagnostic. Diabetes is usually diagnosed before Cushing’s is. If not diagnosed and treated, cats with Cushing’s disease eventually will show some combination of the following signs:
- Failure to respond normally to insulin therapy
- Progressive debilitation despite appropriate administration of potent insulin
- Weight loss, or development of extreme obesity
- Pot-bellied appearance; pendulous abdomen
- Poor hair coat
- Fragile, thin, easily-damaged skin
- Skin ulcerations
- Severe cachexia (overwhelming ill thrift and poor health; overall unkempt appearance)
- Muscle atrophy
- Hair loss (alopecia)
- Poor or delayed wound healing
Skin lesions are often noticed (or actually occur) during grooming or when the cat is handled for physical examination at the veterinary clinic. Several, but not all, of these signs usually appear together.
Cushing's disease is slowly progressive, and very few owners notice that there is anything wrong with their cat until the disease reaches an advanced stage. Frequently, owners attribute the non-specific clinical signs of Cushing’s disease to the normal effects of aging.
Cats at Increased Risk
Middle-aged and older cats – especially females - are most commonly affected by Cushing’s disease. This condition tends to affect mixed-breed cats more than it does purebreds. The reason for this association isn’t well-understood.