title: Prospective cohort study evaluating risk factors for the development of pasture-associated laminitis in the United Kingdom.
abstract: BACKGROUND
  Certain individuals appear to be predisposed to recurrent pasture-associated laminitis. Previous studies have predominantly investigated risk factors only after disease occurrence.
  
  
  OBJECTIVE
  To investigate risk factors for pasture-associated laminitis prior to disease occurrence.
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  Non-laminitic ponies aged ≥7 years were recruited. Body condition score (BCS), height, weight, crest height and thickness were measured and an overnight dexamethasone suppression test performed. Plasma or serum adiponectin, leptin, triglyceride, basal insulin, insulin post-dexamethasone, insulin-like growth factor 1 (IGF-1), IGF binding protein 1 (IGFBP-1), IGFBP-3, C-reactive protein, von Willebrand's factor, soluble E-selectin and P-selectin concentrations were assayed. Follow-up data were obtained from owners annually for 3 years to ascertain occurrences of veterinarian-diagnosed pasture-associated laminitis. Data were analysed by multivariate logistic regression. Receiver operating characteristic (ROC) curves analysis was performed for significant risk factors and cut-off values determined.
  
  
  RESULTS
  A total of 446 animals with a median (interquartile range) age of 15 (10-20) years were recruited. Of these, 50.4% were mares and 49.6% were geldings. The most common breeds were Welsh (36.4%), Shetland (17.0%) and cob (9.4%). Overall, 72.2% of animals were overweight/obese (BCS 7-9/9), 27.3% were of ideal weight (BCS 4-6/9) and 0.5% were underweight (BCS 1-3/9). After 1, 2 and 3 years, respectively, 18 (4.0%), 30 (6.7%) and 44 (9.9%) animals were reported to have had laminitis. Plasma adiponectin, and serum basal (insulin) and (insulin) post-dexamethasone levels were significantly (P ≤ 0.05) associated with laminitis occurrence cumulatively after 1, 2 and 3 years. Use of the area under the ROC curves to distinguish animals that did and did not develop laminitis showed good (basal [insulin] after 1 year), fair (all others) or poor ([insulin] post-dexamethasone) levels of accuracy.
  
  
  CONCLUSIONS
  Animals were evaluated at a single time point and biomarkers were assayed using single assays.
  
  
  CONCLUSIONS
  Risk factors for future laminitis prior to disease occurrence include low plasma adiponectin and high serum basal insulin or insulin post-dexamethasone concentrations.
authors.affiliation: Department of Clinical Sciences and Services, Royal Veterinary College, London, UK.
authors.forename: N J
authors.initials: NJ
authors.lastname: Menzies-Gow
authors.affiliation: Equine Studies Group, Waltham Centre for Pet Nutrition, Waltham on the Wolds, UK.
authors.forename: P A
authors.initials: PA
authors.lastname: Harris
authors.affiliation: Department of Comparative Biomedical Sciences, Royal Veterinary College, London, UK.
authors.forename: J
authors.initials: J
authors.lastname: Elliott
mesh_terms: D000818:Animals; D015331:Cohort Studies; D005260:Female; D005534:Foot Diseases / Q000453:epidemiology / Q000209:etiology / Q000473:pathology / Q000662:veterinary*; D006724:Hoof and Claw / Q000473:pathology*; D006734:Horse Diseases / Q000453:epidemiology / Q000209:etiology*; D006736:Horses; D007249:Inflammation / Q000453:epidemiology / Q000209:etiology / Q000473:pathology / Q000662:veterinary*; D008297:Male; D012307:Risk Factors; D006113:United Kingdom / Q000453:epidemiology
keywords: IGF-1; adiponectin; dexamethasone; horse; insulin; laminitis