title: Disease and pharmacologic risk factors for first and subsequent episodes of equine laminitis: A cohort study of free-text electronic medical records.
abstract: Electronic medical records from first opinion equine veterinary practice may represent a unique resource for epidemiologic research. The appropriateness of this resource for risk factor analyses was explored as part of an investigation into clinical and pharmacologic risk factors for laminitis. Amalgamated medical records from seven UK practices were subjected to text mining to identify laminitis episodes, systemic or intra-synovial corticosteroid prescription, diseases known to affect laminitis risk and clinical signs or syndromes likely to lead to corticosteroid use. Cox proportional hazard models and Prentice, Williams, Peterson models for repeated events were used to estimate associations with time to first, or subsequent laminitis episodes, respectively. Over seventy percent of horses that were diagnosed with laminitis suffered at least one recurrence. Risk factors for first and subsequent laminitis episodes were found to vary. Corticosteroid use (prednisolone only) was only significantly associated with subsequent, and not initial laminitis episodes. Electronic medical record use for such analyses is plausible and offers important advantages over more traditional data sources. It does, however, pose challenges and limitations that must be taken into account, and requires a conceptual change to disease diagnosis which should be considered carefully.
authors.affiliation: Equine Clinical Sciences Division, Weipers Centre Equine Hospital, School of Veterinary Medicine, University of Glasgow, UK. Electronic address: Claire.Welsh@Glasgow.ac.uk.
authors.forename: Claire E
authors.initials: CE
authors.lastname: Welsh
authors.affiliation: School of Veterinary Medicine and Science, University of Nottingham, UK.
authors.forename: Marco
authors.initials: M
authors.lastname: Duz
authors.affiliation: Equine Clinical Sciences Division, Weipers Centre Equine Hospital, School of Veterinary Medicine, University of Glasgow, UK.
authors.forename: Timothy D H
authors.initials: TDH
authors.lastname: Parkin
authors.affiliation: Equine Clinical Sciences Division, Weipers Centre Equine Hospital, School of Veterinary Medicine, University of Glasgow, UK.
authors.forename: John F
authors.initials: JF
authors.lastname: Marshall
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000009:adverse effects*; D015331:Cohort Studies; D057286:Electronic Health Records; D005534:Foot Diseases / Q000139:chemically induced / Q000453:epidemiology / Q000662:veterinary*; D005938:Glucocorticoids / Q000009:adverse effects*; D006734:Horse Diseases / Q000139:chemically induced / Q000453:epidemiology*; D006736:Horses; D007794:Lameness, Animal / Q000139:chemically induced / Q000453:epidemiology*; D012307:Risk Factors; D006113:United Kingdom / Q000453:epidemiology
chemical_list: D000893:Anti-Inflammatory Agents; D005938:Glucocorticoids
keywords: Corticosteroid; Horse; Laminitis; Survival