OBJECTIVE

To investigate mechanisms by which anti-inflammatory doses of orally administered intermediate-acting glucocorticoids (prednisone) could predispose dogs to progression of heart disease or congestive heart failure.

ANIMALS

11 client-owned dogs with allergic dermatitis and 11 matched control dogs.

PROCEDURES

Clinicopathologic, echocardiographic, and hemodynamic variables were measured. Dogs with allergic dermatitis then received prednisone (1 mg/kg, PO) once daily for 14 consecutive days beginning on day 0 (baseline), followed by a tapering and washout period; control dogs received no treatment. Measurements were repeated on days 7, 14, and 35. Linear mixed modeling was used to compare changes in variables across measurement points and between dog groups.

RESULTS

Prednisone administration caused no significant changes in serum sodium or potassium concentration, blood glucose concentration, or target echocardiographic variables. The change from baseline in systolic arterial blood pressure at day 7 was significantly greater in the prednisone-treated dogs than in control dogs. Expected changes in hematologic and serum biochemical values with prednisone administration (neutrophilia, eosinopenia, isosthenuria, and high serum alkaline phosphatase and alanine aminotransferase activities) also occurred in the prednisone-treated dogs.

CONCLUSIONS AND CLINICAL RELEVANCE

Findings suggested that anti-inflammatory doses of orally administered glucocorticoids have the potential to adversely impact cardiac function in dogs by causing an increase in blood pressure and thus increased cardiac afterload.