Incidences of steroid-induced diabetes mellitus and congestive heart failure in cats given non-immunosuppressive doses of methylprednisolone acetate: 1042 cats.

Objective: Corticosteroids are indicated to treat many feline diseases. However, side effects are a limiting factor in their use. The most concerning side effects are steroid-induced diabetes mellitus (SI-DM) and steroid-induced congestive heart failure (SI-CHF). This study aims to determine the incidences of these diseases in a large population of domestic cats seen at a privately-owned, feline-only practice.

Animals: Cats in the study were client-owned patients of Alamo Feline Health Center in San Antonio, Texas. Control cats (controls) were examined as part of their routine health care.

Procedures: The records of 732 cats that received methylprednisolone acetate (MPA) for various clinical indications were reviewed to determine how many developed SI-DM and SI-CHF. A similar record review of 310 controls was made to determine the incidence of spontaneous diabetes mellitus (Sp-DM) and spontaneous congestive heart failure (Sp-CHF). Control cats never received any oral or injectable corticosteroids.

Results: Of the cats that received MPA, 28 developed SI-DM (3.83%) and 6 developed SI-CHF (0.82%). Of the controls, 22 developed Sp-DM (7.10%) and 6 developed Sp-CHF (1.90%).

Conclusion: The incidences of developing SI-DM and SI-CHF were 3.83% and 0.82%, respectively; and the risk was not increased even when repeated doses of MPA were given.

Clinical Relevance: The authors consider the risk-benefit ratio sufficient to justify the use of MPA when it is indicated, especially if another drug cannot be substituted with the same therapeutic results.