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Equine veterinary journal2021; 54(5); 905-913; doi: 10.1111/evj.13529

Variation in insulin response to oral sugar test in a cohort of horses throughout the year and evaluation of risk factors for insulin dysregulation.

Abstract: The oral sugar test (OST) is commonly used to diagnose insulin dysregulation (ID) and equine metabolic syndrome; however, possible seasonal changes in OST results have not been evaluated. Objective: To determine the possible variation in insulin response to OST throughout the year and risk factors associated with maximum insulin concentration (InsMax) and ID. Methods: Prospective, longitudinal cohort study. Methods: The OST was performed on 29 Finnhorses every other month six times. Serum total adiponectin concentration and phenotypic variables related to obesity were also measured. Changes in InsMax, adiponectin, scale weight, body condition score, cresty neck score (CNS), and fasting glucose concentration were assessed. Risk factor analyses were performed on InsMax and ID status, and ID groups were compared with each other. Results: Fourteen horses were categorised with non-ID each time and 15 as having ID at least once during the follow-up period. The ID status of 12 horses varied throughout the year, but neither the insulin variables measured during the OST nor adiponectin expressed significant seasonal variation. Increasing age and CNS, and decreasing adiponectin were observed as risk factors for a high InsMax after OST. The risk of ID was higher in horses with no exercise compared to horses with exercise (OR 7.6, 95% CI 1.2-49.3, P = .03). Horses with ID had lower serum adiponectin concentrations, longer neck circumference and larger height than horses in the non-ID group. Conclusions: The environmental conditions (feeding, exercise) were not constant for all horses throughout the study and only one breed was used. Conclusions: Neither OST results nor adiponectin varies with season; however, there were a substantial number of horses with variable ID status throughout the year, in which repeated OSTs may be beneficial. Lack of exercise was a risk factor for ID.
Publication Date: 2021-11-08 PubMed ID: 34713928PubMed Central: PMC9545906DOI: 10.1111/evj.13529Google Scholar: Lookup
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  • Journal Article

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 paper focuses on the exploration of insulin response variations in the Oral Sugar Test (OST) carried out in 29 horses over a period of time and identifies possible risk factors associated to insulin dysregulation and maximum insulin concentration. It unveils key insights such as a lack of exercise posing a risk factor for insulin dysregulation.

Methods

The research study followed a prospective, longitudinal cohort model in which the OST was carried out on 29 Finnhorses periodically – every other month over the span of a year. The researchers also recorded serum total adiponectin concentration along with other obesity-related phenotypic variables.

  • Changes in maximum insulin concentration (InsMax), adiponectin, scale weight, body condition score, cresty neck score (CNS), and fasting glucose concentration were assessed and recorded systematically.
  • Risk factors for InsMax and Insulin Dysregulation (ID) status were analyzed and groups with and without ID were compared against each other.

Results

The OST results were carefully evaluated in the course of the study.

  • Throughout the study period, 14 horses were consistently categorized as non-ID, while 15 experienced ID at least once.
  • The ID status of 12 horses varied throughout the year, testament to changing insulin response over different periods.
  • The research noted no significant seasonal variation in neither the insulin variables measured during the OST nor the levels of adiponectin in horses.
  • The study sheds light on factors such as increasing age and CNS, and decreasing adiponectin that contribute to high InsMax post OST.
  • The study revealed that lack of exercise posed a higher risk of ID in horses when compared to horses with exercise.
  • Horses with ID were found to have comparatively lower serum adiponectin concentrations, longer neck circumference, and larger height than horses in the non-ID group.

Conclusion

While the study acknowledges inadequacies such as variability in environmental conditions (feeding, exercise) and the exclusive use of one horse breed, it makes significant conclusions.

  • The study concludes that the results of OST and adiponectin levels do not display seasonal variations.
  • The researchers also note that several horses exhibited variable ID status throughout the year, thereby suggesting the potential necessity for repeated OSTs.
  • Among the risk factors for insulin dysregulation, a lack of regular physical exercise was identified, providing clear direction for preventive care and attention.

Cite This Article

APA
Karikoski NP, Box JR, Mykkänen AK, Kotiranta VV, Raekallio MR. (2021). Variation in insulin response to oral sugar test in a cohort of horses throughout the year and evaluation of risk factors for insulin dysregulation. Equine Vet J, 54(5), 905-913. https://doi.org/10.1111/evj.13529

Publication

ISSN: 2042-3306
NlmUniqueID: 0173320
Country: United States
Language: English
Volume: 54
Issue: 5
Pages: 905-913

Researcher Affiliations

Karikoski, Ninja P
  • Department of Equine and Small Animal Sciences, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland.
Box, Justin R
  • Department of Equine and Small Animal Sciences, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland.
Mykkänen, Anna K
  • Department of Equine and Small Animal Sciences, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland.
Kotiranta, Veikko V
  • Department of Equine and Small Animal Sciences, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland.
Raekallio, Marja R
  • Department of Equine and Small Animal Sciences, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland.

MeSH Terms

  • Adiponectin
  • Animals
  • Blood Glucose / metabolism
  • Glucose Tolerance Test / veterinary
  • Horse Diseases / diagnosis
  • Horses
  • Insulin / metabolism
  • Longitudinal Studies
  • Prospective Studies
  • Risk Factors

Grant Funding

  • The Finnish Foundation of Veterinary Research
  • Erkki Rajakoski Foundation
  • The Finnish Veterinary Research Foundation
  • The Doctoral Programme in Clinical Veterinary Medicine, University of Helsinki

Conflict of Interest Statement

No competing interests have been declared.

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Citations

This article has been cited 7 times.
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