Insulin Resistance in Horses : An Equine Metabolic Syndrome

Analogous to the situation in human medicine, contemporary practices in horse management, which incorporate lengthy periods of physical inactivity coupled with provision of nutritional rations characterized by inappropriately high sugar and starch, have led to obesity being more commonly recognized by practitioners of equine veterinary practice. In many of these cases, obesity is associated with insulin resistance (IR) and glucose intolerance. An equine metabolic syndrome (MS) has been described that is similar to the human MS in that both IR and aspects of obesity represent cornerstones of its definition. Unlike its human counterpart, identification of the equine metabolic syndrome (EMS) portends greater risk for development of laminitis, a chronic, crippling affliction of the equine hoof. When severe, laminitis sometimes necessitates euthanasia. Unlike the human condition, the risk of developing type 2 diabetes mellitus and many other chronic conditions, for which the risk is recognized as increased in the face of MS, is less likely in horses. The equine veterinary literature has been replete with reports of scientific investigations regarding the epidemiology, pathophysiology, and treatment of EMS. J Diabetes Sci Technol 2012;6(3):534-540 SYMPOSIUM Insulin Resistance in Horses: An Equine Metabolic Syndrome Increasing recognition of the relevance of insulin resistance (IR) to health in horses has somewhat paralleled that reported in the human medical field.1–3 Although specific definitions differ somewhat, the presence of IR is an important component of metabolic syndrome (MS) in human patients.4–6 Other clinical abnormalities that contribute to the definitions of MS include an increased body mass index, central obesity, hypertriglyceridemia and dyslipidemia, elevated blood pressure, microalbuminuria, and elevated biomarkers for the