Associations among serum insulin, calprotectin, and C‐reactive protein concentrations in Miniature Schnauzers with idiopathic hyperlipidemia before and after feeding an ultra‐low‐fat diet

BACKGROUND: Miniature Schnauzers (MS) commonly have idiopathic hypertriglyceridemia (HTGL), which is associated with insulin resistance (IR) and a subclinical inflammatory phenotype. OBJECTIVES: Determine the association between indicators of IR and inflammatory biomarkers in MS with and without HTGL and identify how indicators of IR are affected by dietary intervention in MS with HTGL. ANIMALS: Seventy MS with HTGL and 79 MS without HTGL. In addition, 15 MS with HTGL were placed on a low‐fat diet. METHODS: Serum concentrations of triglycerides, cholesterol, calprotectin, insulin, and glucose were compared between groups. RESULTS: Serum glucose and calprotectin concentrations (shown to be higher in MS with HTGL than in MS without HTGL) were inversely correlated (ρ = −.28; P < .001). After dietary intervention, median serum insulin concentrations were 8.1 mU/L compared to 20.8 mU/L before dietary intervention (P = .06). Dogs with complete resolution of HTGL after dietary intervention (5 dogs) had significantly lower serum insulin concentrations compared to baseline (P = .03). CONCLUSION AND CLINICAL IMPORTANCE: The subclinical inflammatory phenotype in MS with HTGL appears to be associated with IR. Resolution of HTGL by dietary intervention is associated with a decrease in serum insulin concentrations. The implication of the increase in serum calprotectin concentrations after resolution of HTGL warrants further study.