Cardiovascular Complications in Cushing's Disease

Pathophysiology

• Cortisol excess enhances vascular reactivity to vasoconstrictors and activates mineralocorticoid receptors, leading to sodium retention and volume expansion, according to the American Heart Association 1
• Hypokalemia, a common finding in Cushing's disease, can directly cause tachycardia, as reported by the American College of Cardiology 1, 2
• Electrolyte imbalances can trigger cardiac arrhythmias, including tachycardia, according to the American College of Cardiology 2

Epidemiology

• 70-90% of Cushing's disease patients have hypertension, which is a major contributor to cardiovascular risk, as reported by the American Heart Association 1
• Cushing disease accounts for 75-80% of pediatric Cushing syndrome cases, with microadenomas (<10mm) accounting for 98% of cases in children and adolescents, according to the Endocrine Society and Pediatric Endocrine Society guidelines 3

Clinical Presentation

• Tachycardia in a patient with suspected Cushing's disease should prompt evaluation of electrolytes, particularly potassium, and screening for sleep apnea, as recommended by the American College of Cardiology 1, 2
• Consideration of cardiac monitoring if severe tachycardia is present is advised, according to the American Heart Association 4
• Children with unexplained weight gain combined with either growth rate deceleration or height centile decrement should be investigated for Cushing syndrome, as recommended by the American Academy of Pediatrics 3
• Hypokalemia is present in up to 57% of patients with ectopic ACTH syndrome, and purple striae, easy bruising, and muscle atrophy are common manifestations of Cushing syndrome, according to the National Comprehensive Cancer Network and The Lancet Diabetes and Endocrinology 5, 6

Diagnosis

• The diagnostic approach for Cushing syndrome involves initial screening tests, including:

  Test	Sensitivity	Specificity
  UFC	>90%	-
  LNSC	>90%	100%
  1-mg DST	-	(cutoff <1.8 μg/dL)

• Confirmation of ACTH dependence/independence is crucial, with plasma ACTH levels helping to distinguish adrenal causes from ACTH-dependent forms, as reported by The Lancet Diabetes and Endocrinology 6

Management

• Treatment of the underlying Cushing's disease is the definitive approach, and surgical excision of ACTH-producing tumor can effectively lower blood pressure and may normalize heart rate, as stated by the Endocrine Society 1, 6
• Mineralocorticoid receptor antagonists (spironolactone, eplerenone) are particularly effective for managing hypertension and related cardiovascular effects in Cushing's syndrome, as recommended by the American Heart Association 1
• Potassium supplementation may be necessary to correct hypokalemia, according to the American College of Cardiology 2

• Medical therapy with steroidogenesis inhibitors, such as osilodrostat, metyrapone, and ketoconazole, is an option for persistent or recurrent disease, with response rates and side effects as follows:

  Drug	Dose	Efficacy	Side Effects
  Osilodrostat	2-7 mg/day	86%	Adrenal insufficiency, androgen effects
  Metyrapone	500 mg/day to 6 g/day	~70%	Hirsutism, hyperandrogenism
  Ketoconazole	400-1200 mg/day	~65%	Liver function abnormalities

• The first-line approach for treating hypertension related to cortisol imbalance in Cushing's syndrome involves surgical removal of the ACTH or cortisol-producing tumor, which provides definitive treatment with 60-80% remission rates for microadenomas, as recommended by the European Society of Endocrinology 1, 6
• Approximately 30% of patients will have persistent hypertension despite successful treatment of cortisol excess, and risk factors include older age at presentation, longer duration of hypertension before treatment, and higher systolic blood pressure before treatment, highlighting the need for regular cardiovascular risk assessment and aggressive management of persistent comorbidities even after biochemical cure 1

Cardiovascular Risk Management

• The European Society of Cardiology and American Heart Association recommend high-intensity statin therapy to reduce Major Adverse Cardiovascular Events (MACE) risk in patients with Cushing's syndrome, with a goal of LDL-C reduction of ≥50% from baseline and absolute level <1.4 mmol/L (55 mg/dL), using medications such as atorvastatin 40-80 mg or rosuvastatin 20-40 mg daily 7, 8
• The American Diabetes Association recommends metformin as first-line therapy for patients with diabetes or impaired glucose tolerance, with a target HbA1c <7.0% while avoiding hypoglycemia, and the European Association for the Study of Diabetes suggests GLP-1 receptor agonists or SGLT2 inhibitors may be added for additional glycemic control and cardiovascular benefit in patients with Cushing's syndrome 7, 8
• The American Heart Association recommends dietary counseling focusing on low-sodium, Mediterranean-style diet, and a structured exercise program as tolerated, considering myopathy limitations, for patients with Cushing's syndrome, and the European Society of Cardiology suggests GLP-1 receptor agonists may be considered for weight management in appropriate patients with Cushing's syndrome 7, 8

Special Considerations

• In pregnancy, metyrapone may be considered with precautions, and a higher cortisol target (1.5 × ULN) is recommended due to normally higher cortisol during pregnancy, according to the Endocrine Society guidelines 6
• In pediatric patients, lifelong monitoring for recurrence, management of persistent comorbidities, and monitoring of growth, pubertal progression, and GH deficiency testing are necessary, as recommended by the European Society of Endocrinology 3
• Combination therapy may be necessary, with common combinations including ketoconazole + metyrapone, and steroidogenesis inhibitor + tumor-targeting agent, as recommended by the European Society of Endocrinology 6
• Long-term monitoring is essential due to the risk of recurrence, persistent comorbidities, and need for hormone replacement in cases of adrenal insufficiency, as emphasized by the Endocrine Society 3
• Thromboprophylaxis is recommended, especially in the perioperative period, and should be extended up to 30 days postoperatively, as suggested by the Endocrine Society 6
• Hormone replacement therapy may be necessary for patients with post-treatment adrenal insufficiency, with dose adjustments during stress situations 9