Abstract Background The association of plasma cortisol concentration with prognosis for dogs with congestive heart failure (CHF) is unknown. Hypothesis/Objectives To determine whether higher plasma cortisol concentration was independently associated with greater risk of cardiac mortality in dogs with CHF. Additional study aims were to evaluate the associations between other clinical, neurohormonal, and echocardiographic indices and cardiac mortality. Animals Thirty-one client-owned dogs with CHF secondary to myxomatous mitral valve disease (MMVD). Methods Prospective cohort observational study. Plasma cortisol measurement, urine cortisol-to-creatinine ratio, renal function test results, serum electrolytes, biomarkers of the renin–angiotensin–aldosterone system, N-terminal pro-B-type natriuretic peptide, and echocardiography were performed in dogs with MMVD at first onset of CHF. Plasma cortisol was repeated 7-14 days later. Association between plasma cortisol and other covariates with survival was determined using a proportional hazards regression model. Results Plasma cortisol concentration was not associated with cardiac (P = .112; hazard ratio HR 1.01; 95% CI, 0.998-1.02) or all-cause mortality (P = .143; HR 1.01; 95% CI, 0.998-1.02). Treatment with angiotensin-converting enzyme inhibitors (P = .021; HR 0.058; 95% CI, 0.0052-0.66) was associated with longer survival to cardiac mortality. Treatment with spironolactone (P = .038; HR 0.36; 95% CI, 0.14-0.94), percent fractional shortening (P = .034; HR 0.0018; 95% CI, 5.44 × 10−6 to 0.61), and lower serum potassium (P = .048; HR 2.07; 95% CI, 1.01-4.27) at diagnosis were associated with longer survival to all-cause mortality. Spironolactone treatment at baseline was associated with all-cause mortality on multivariable regression analysis. Conclusions and clinical importance Plasma cortisol concentrations were not associated with cardiac mortality in this sample of dogs with CHF.
Masters et al. (2026) studied this question.