Equine Cushing's disease is a condition of aged horses, ie over 15 years of age, and is a result of a number of hormone related problems that derive from changes in the brain. It is also known as pituitary pars intermedia dysfunction (PPID) and hyperadrenocorticism. It is sometimes called Cushing's syndrome suggesting that it is a disease with a variety of symptoms, some of which may be present at any one time. Equine Cushing's disease is notably different in many respects from the condition with the same name in dogs and humans. Cushing's disease cannot be cured, but treatment is sometimes effective and can prolong and improve the quality of life for affected horses. All types of horse can be affected - ponies commonly seem to be predisposed because they tend to live longer!