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Home / Equine Research Bank / Vet J / Epidemiology of pituitary pars intermedia dysfunction: A sys...
Veterinary journal (London, England : 1997)2018; 235; 22-33; doi: 10.1016/j.tvjl.2018.03.002

Epidemiology of pituitary pars intermedia dysfunction: A systematic literature review of clinical presentation, disease prevalence and risk factors.

Abstract: Pituitary pars intermedia dysfunction (PPID) is caused by an age-related degenerative disease of dopaminergic neurones. Despite its importance in equine practice, available information regarding its epidemiology is limited. This systematic review aimed to assess published literature to evaluate available evidence regarding the clinical presentation, prevalence and risk factors for PPID in horses and ponies. Electronic database searches were undertaken using a range of terms, and English language publications published prior to August 2016 were included. Both authors independently reviewed screened papers for inclusion, extracted data, and assessed the quality of reporting using predefined criteria. Data were extracted using modified critically appraised topic data collection forms. Meta-analysis was not undertaken due to marked between-study variations. Following removal of duplicate records, of 358 published papers yielded by the search, 97 abstracts were screened for eligibility and 29 publications meeting inclusion criteria were included in the review. Most studies reviewed were case series or cross-sectional studies, with considerable variation in study populations and PPID case definition. Hypertrichosis and/or other hair coat abnormalities, laminitis and epaxial muscle wastage or muscle atrophy are the most frequently reported clinical signs, with prevalence of these signs increasing with increasing horse age. The most robust prevalence estimates for PPID were 21.2% in horses and ponies aged ≥15 years and 2.9% amongst the general equine population. Findings regarding breed and sex predispositions were equivocal and only increasing age has been identified as a significant risk factor for PPID.
Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.
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Publication Date: 2018-03-08 PubMed ID: 29704935DOI: 10.1016/j.tvjl.2018.03.002Google Scholar: Lookup
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  • Journal Article
  • Review
  • Systematic Review

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research article reviews published literature on the epidemiology of Pituitary pars intermedia dysfunction (PPID), a degenerative disease in horses and ponies. The review includes assessments of the clinical presentation, prevalence and risk factors for this aging-related disease, with a specific focus on its presentation, prevalence, and associated risk factors.

Disease Overview

  • Pituitary pars intermedia dysfunction (PPID) is a degenerative condition affecting the aging population of horses and ponies.

Research Methodology

  • The researchers conducted a systematic review by extensively searching different databases for relevant literature published before August 2016, all of which were in the English language.
  • Of the 358 papers found initially, the number was refined to 29 after a rigorous eligibility screening by the authors.
  • The authors then extracted relevant data from these papers and evaluated their quality using predefined criteria. Questions of definition, variance in study populations, and statistical limitations prevented their capacity to run a meta-analysis.

Study Findings

  • The majority of studies were either case series or cross-sectional studies, presenting a variety of population samples and PPID case definitions.
  • Clinical symptoms of PPID commonly reported in the studies included abnormalities in hair coat, laminitis, and muscle wasting or atrophy, all of which become more commonplace with increasing horse age.
  • The most proficient prevalence estimates for PPID in the literature were found to be 21.2% in equine aged 15 years and above and 2.9% across general equine demographics.
  • However, the research findings regarding breed and gender predispositions towards PPID were found to be inconclusive; only age was identified as a significant risk factor contributing to PPID.

Conclusion

  • Though PPID is a significant problem in equine practice, information on its epidemiology remains limited. The review indicates that further in-depth and standardized research is required to gain better insights about the disease’s epidemiological characteristics and risk factors.

Cite This Article

APA
Ireland JL, McGowan CM. (2018). Epidemiology of pituitary pars intermedia dysfunction: A systematic literature review of clinical presentation, disease prevalence and risk factors. Vet J, 235, 22-33. https://doi.org/10.1016/j.tvjl.2018.03.002

Publication

Veterinary journal (London, England : 1997)
ISSN: 1532-2971
NlmUniqueID: 9706281
Country: England
Language: English
Volume: 235
Pages: 22-33
PII: S1090-0233(18)30064-9

Researcher Affiliations

Ireland, J L
  • Department of Equine Clinical Science, Institute of Veterinary Science, Leahurst Campus, The University of Liverpool, Wirral, CH64 7TE, United Kingdom.
McGowan, C M
  • Department of Equine Clinical Science, Institute of Veterinary Science, Leahurst Campus, The University of Liverpool, Wirral, CH64 7TE, United Kingdom. Electronic address: cmcgowan@liverpool.ac.uk.

MeSH Terms

  • Aging
  • Animals
  • Female
  • Horse Diseases / epidemiology
  • Horses
  • Male
  • Neurodegenerative Diseases / complications
  • Neurodegenerative Diseases / veterinary
  • Pituitary Diseases / epidemiology
  • Pituitary Diseases / etiology
  • Pituitary Diseases / veterinary
  • Pituitary Gland, Intermediate
  • Risk Factors

Citations

This article has been cited 26 times.
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