Hypertension was common and associated with serum cholesterol concentrations in dogs with Cushing syndrome

Objective To estimate the prevalence of systemic hypertension in dogs with newly diagnosed Cushing syndrome (CS) and evaluate associations with hypothesized hypertension-associated variables. Methods A retrospective observational study was performed with dogs diagnosed with CS by ACTH stimulation or low-dose dexamethasone suppression testing at University of Wisconsin Veterinary Care from 2005 to 2025. Dogs with systolic blood pressure (SBP) measured within 8 weeks of diagnosis and before CS or antihypertensive treatment were included. Data included signalment, body condition score, platelet count, select serum biochemistry variables, and urine protein-to-creatinine ratio. Hypertension prevalence and associations between SBP and variables were assessed. Results Among 117 dogs with CS, 57 dogs (49%) had SBP measured and met inclusion criteria. With an SBP cutoff ≥ 160 mm Hg, 61.4% of dogs (95% CI, 48.4% to 73.0%) were hypertensive and 26.3% were prehypertensive (SBP of 140 to 159 mm Hg). Median serum cholesterol was higher in hypertensive than nonhypertensive dogs (378.5 vs 287 mg/dL) and positively associated with SBP (OR, 1.10/10 mg/dL; 95% CI, 1.03 to 1.21). Serum potassium was lower in hypertensive dogs than nonhypertensive dogs (4.4 vs 4.85 mmol/L). No significant associations were identified for urine protein-to-creatinine ratio, platelet count, age, or body condition score. Conclusions Hypertension was common in dogs with CS, yet SBP was not consistently measured at diagnosis. Serum cholesterol was associated with hypertension, and lower serum potassium concentrations were observed in hypertensive dogs. Clinical Relevance Routine SBP assessment is warranted in dogs with CS. Cholesterol and potassium regulation may be affected in dogs with CS.