Effectiveness of Medical Treatment on Survivability in Canine Cushing’s Syndrome: A Systematic Review and Meta-Analysis

Abstract

Cushing’s syndrome is one of the most common endocrine disorders in dogs and is typically managed with long-term medical treatment. Several pharmacological agents are available: trilostane, mitotane, ketoconazole, cabergoline, selegiline, and aminoglutethimide, but their comparative effects on survival remain unclear. This systematic review and meta-analysis compared the impact of these agents on survival outcomes in dogs with naturally occurring diseases. A comprehensive search of MEDLINE, Embase, Web of Science, Academic Search Complete, and the Cochrane Library was conducted between 1 September 2024 to 3 January 2025. Eligible studies included dogs diagnosed with Cushing’s syndrome that reported survival outcomes for at least one of the specified treatments. Five studies (n = 295 dogs) met the inclusion criteria, with trilostane and mitotane providing sufficient data for meta-analysis. Pooled mean difference in survival time across four studies was 85.1 days (95% CI: −255.9 to 85.7, <i>p</i> = 0.21) with substantial heterogeneity (I² = 89%), indicating no statistically significant difference between the drugs. In contrast, pooled survival rates at fixed intervals favored trilostane, with an 11% higher survival at 36 months (<i>p</i> = 0.005) and no heterogeneity observed (I² = 0%). These findings suggest trilostane may offer long-term survival benefits over mitotane.