PPID may not shorten horses’ lives, but it raises care needs

A new study is offering a more nuanced prognosis for horses with pituitary pars intermedia dysfunction: they may live just as long as comparable horses without PPID, but they’re likely to face more medical issues along the way. In the retrospective case-control analysis, researchers found no shorter lifespan in horses diagnosed with PPID, yet documented a higher frequency of medical events, including poor healing, dental problems, and hyperinsulinemia-associated laminitis. The findings were highlighted in AVMA’s Veterinary Vertex podcast and summarized by The Horse. (pubmed.ncbi.nlm.nih.gov)

That distinction matters because PPID has long carried a heavy prognosis in the minds of some clinicians and pet parents, partly because much of the earlier literature came from referral populations that skew toward more severe or complicated cases. In the podcast discussion, the authors said they specifically wanted to understand what PPID looks like in first-opinion practice, where case mix and management patterns may better reflect the real-world population seen by ambulatory and general equine veterinarians. To do that, they matched controls by age, breed type, and owner, an attempt to reduce confounding from management style, testing behavior, and willingness to pursue care. They also limited controls to horses 11 years and older so they had survived to a comparable age range, helping avoid unfair comparisons with younger animals less likely to have developed age-related disease. (veterinaryvertex.buzzsprout.com)

According to the PubMed abstract, the study reviewed records from 1996 to 2024 and included 132 horses with PPID and 274 matched controls. Median age at euthanasia was 26 years for horses with PPID, compared with 24 years for controls. After analysis, the factors independently associated with PPID were poor healing, dental issues, hyperinsulinemia-associated laminitis, and being prescribed NSAIDs. The clinical relevance statement was straightforward: horses with PPID did not have shorter life expectancies, but they did experience more medical events during their lifetime. (pubmed.ncbi.nlm.nih.gov)

The broader PPID literature helps explain why this result is landing now. PPID is increasingly recognized as a common disorder of older horses, with one older prevalence study finding the condition in 21.2% of aged horses, even though pet parents often did not report it as a known diagnosis. More recently, industry and academic groups have put more emphasis on screening and diagnosis, including Boehringer Ingelheim’s seasonal testing program with Cornell, which has tested more than 50,000 horses since 2013. In the Veterinary Vertex interview, the study authors suggested the apparent rise in cases likely reflects better detection, not necessarily a true increase in prevalence. (pubmed.ncbi.nlm.nih.gov)

There’s also growing support for active long-term treatment once PPID is diagnosed. Reporting from the 2022 AAEP Convention described a 13-year pergolide follow-up study in which treated horses generally showed sustained improvement in clinical signs and quality of life, even though pergolide did not appear to prolong life. After 10 years of treatment, 96% of surveyed horse owners agreed or strongly agreed that pergolide improved their horse’s quality of life, and nearly three-fourths said they would invest at least $1,000 per year for lifelong treatment. That context reinforces the new study’s central message: survival may be preserved, but maintaining that outcome likely depends on ongoing management. (thehorse.com)

Expert commentary around the new paper has leaned in that direction. On the AVMA podcast, coauthor François René-Bertin said PPID is “not a death sentence” and urged veterinarians to test and treat cases rather than dismiss changes as normal aging. He also noted a possible surveillance effect: horses receiving daily medication may be observed more closely, which could increase detection of minor problems and partially explain the higher number of recorded medical events. That’s an inference worth keeping in mind when interpreting retrospective record data from primary care. The authors also emphasized that their goal was to give practitioners a clearer day-to-day picture of PPID on the farm, not just in referral settings where disease severity and owner follow-through may differ substantially. (veterinaryvertex.buzzsprout.com)

Why it matters: For veterinary professionals, the study supports a shift from fatalistic counseling to chronic-disease management planning. The practical message for equine practice is that a PPID diagnosis should trigger structured monitoring for laminitis, dental pathology, wound healing complications, and analgesic use, rather than an assumption of near-term decline. Because the comparison group was matched not just by age and breed but also by owner, the findings may be especially useful for frontline clinicians trying to separate disease burden from differences in management and care-seeking behavior. It also strengthens the case for routine screening in older horses and for setting expectations with pet parents that these patients may live for years, but often with a higher care burden and more touchpoints with the veterinary team. (pubmed.ncbi.nlm.nih.gov, veterinaryvertex.buzzsprout.com)

What to watch: The next step will be whether these findings change frontline practice patterns, especially around earlier testing, standardized follow-up, and how clinicians distinguish true PPID-related morbidity from increased surveillance in closely managed horses. Additional primary-care studies, ideally prospective ones, could help clarify that question and refine prognosis discussions even further. (veterinaryvertex.buzzsprout.com)