A prospective clinical study examined the relationship between insulin levels and laminitis severity in 25 horses and ponies with equine metabolic syndrome (EMS), equine Cushings disease (ECD) and controls.

Horses with naturally occurring laminitis as well as EMS or ECD were selected for the study along with unaffected controls from the same premises.  Blood samples were collected with assessments of weight, body condition, neck crest and soundness 11 times over a period of 1 year.  Horses with ECD were treated with peroglide and horses with EMS were placed on low carb, reduced calorie diets with exercise.

There was a significant positive correlation between laminitis Obel grade (a measure of severity based on pain) and plasma insulin concentration.  There was also a correlation between the improvement in Obel grades and lower insulin levels over the course of the study.

These result highlight the link between high blood insulin levels (insulin resistance) and laminitis and suggest insulin plays a role in the cause of laminitis among EMS horses.  This work also suggest blood insulin levels may be a useful predictor of laminitis risk in susceptible horses.

Walsh et al. JEVS 2009;29:87-94