It has no cure. Diagnostic options are limited. And it affects a larger proportion of senior horses. But fortunately, it's treatable. This disease is pituitary pars intermedia dysfunction (PPID, formerly referred to as equine Cushing's disease). | Photo: iStock

Weighing the pros and cons of pituitary pars intermedia dysfunction tests old and new

In decades past, owners and veterinarians simply attributed many conditions for which nothing could be done to “old age.” Today we have specific diagnoses and treatments for several of these once-hopeless issues. One such disease is pituitary pars intermedia dysfunction (PPID), also referred to as equine Cushing’s disease. Australian researchers recently estimated that PPID occurs in 21% of horses over age 15, and animals in this age group are at an increased risk of developing the condition.  

Veterinarians can diagnose advanced PPID based on a horse’s physical appearance. Andy Durham, BSc, BVSc, CertEP, DEIM, Dipl. ECEIM, MRCVS, a partner at Liphook Equine Hospital, in the U.K., and a leading equine Cushing’s specialist, reports, “The commonest signs are laminitis, muscle wastage, slow or incomplete shedding of a long, curly winter coat, susceptibility to infections, and excess thirst with excess urination.”  

Nicholas Frank, DVM, PhD, Dipl. ACVIM, professor of large animal medicine at Tufts Cummings School of Veterinary Medicine, adds that PPID is a particular concern in horses that already suffer from insulin problems (insulin is an important hormone responsible for regulating the blood concentration of glucose, the body’s most important fuel molecule) as part of equine metabolic syndrome (EMS, a metabolic and hormonal disorder characterized by obesity, regional adiposity, insulin resistance, and laminitis)