Pituitary pars intermedia dysfunction in horses: retrospective analysis of clinical cases and clinicians' perspective of the disease

Abstract

The increase in patient longevity observed nowadays in equine medicine is directly linked to the improvement in the veterinary care provided to these animals. As longevity increases, pathologies linked to geriatric age also present an increasing tendency in prevalence. Included in this group of age-linked diseases, pituitary pars intermedia dysfunction (PPID) represents the main endocrine disease affecting geriatric horses and ponies worldwide. In spite of the clinical relevance of the disease, there are some knowledge gaps that need to be fulfilled. In order to get a better knowledge of the disease, systematic online questionnaires were used to evaluate the perception towards this disease from Spanish equine veterinarians and equine owners with PPID-diagnosed animals. A total of 20 responses were obtained from Spanish veterinarians. 65% of veterinarians based their diagnosis on a combination of clinical presentation and laboratory findings; however. 60% of the veterinarians considered that the current treatments for PPID were adequate but could be improved, 25% considered it adequate and 15% considered it not adequate. 95% of the veterinarians considered that PPID is an underdiagnosed pathology. The equine veterinarians considered that the main reason for infradiagnosis of PPID was owners’ hesistance (35%), treatment cost (28%), diagnosis cost (18%), veterinarian unawareness of the disease (15%), and old age of the horse (5%). When asked about those diagnosed PPID cases that are not treated, the main reasons were economic factors (60%), difficulties in sourcing the treatment (16%), and the need for daily dosage (12%). 86 responses were obtained from PPID-diagnosed equine owners. The mean age of the animals evaluated was 23.71 (±4.7) years. Hirsutism was the most common symptom, followed by laminitis and muscular atrophy. 55.8% of the horses showed general improvement after treatment, 39.5% showed partial improvement, and 4.7% showed no improvement after treatment. Veterinarian and owners’ awareness of the relevance of this disease should be improved in order to enhance the wellbeing of geriatric horses and ponies. For this reason, early and correct diagnosis and treatment of PPID is key to prevent associated pathologies and to increase the owner’s involvement in controlling this significant equine pathology.