Cushing's disease is a rare subtype of Cushing’s syndrome caused by a benign pituitary tumor that overproduces adrenocorticotropic hormone (ACTH), leading to increased cortisol production by the adrenal glands. This condition can disrupt normal cortisol rhythms and may contribute to serious complications if not managed appropriately. It is important to consult with a healthcare provider for diagnosis and treatment options.
Surgery is often the primary approach for addressing Cushing's disease because it targets the underlying cause. However, medications can also play a significant role in managing Cushing’s disease.
Medication may be used for individuals with persistent or recurrent symptoms after surgery, for those who are not candidates for surgery, or in situations where rapid cortisol management is needed due to severe hypercortisolism or potential complications.
In this article, we’ll explore the medications available for managing Cushing's Disease, including a discussion of their uses, how they work, and what individuals can expect from medication use as they manage Cushing’s disease.
[signup]
Understanding the Role of Cortisol in Cushing’s Disease
Excessive cortisol levels, or cortisolemia, are a key factor in the disease process seen in Cushing’s.
What is Cortisol?
Cortisol, a glucocorticoid hormone, is often called a stress hormone because it is foundational to our stress response. However, cortisol has many roles in normal human physiology.
Cortisol:
- Regulates metabolism (promoting gluconeogenesis and reducing glucose uptake)
- Modulates the immune response (by suppressing inflammation)
- Supports the stress response (mobilizing energy and increasing alertness through neuroendocrine signaling pathways)
- Increases blood pressure (enhancing vasoconstriction and increasing blood volume)
- Influences fluid and electrolyte balance (promoting sodium and water reabsorption and potassium excretion)
- Affects mood and behavior
- Supports fetal lung and nervous system development
- Regulates the sleep-wake cycle
- Maintains bone health by balancing bone formation and resorption
How Cushing’s Disease Affects Cortisol Production
Cushing’s syndrome is the general condition that refers to the condition of hypercortisolism, while Cushing’s disease specifically refers to hypercortisolism due to an ACTH-secreting pituitary tumor.
The pathophysiology of Cushing's syndrome involves prolonged exposure to high levels of cortisol.
In Cushing’s disease, the pituitary adenoma secretes excessive ACTH which stimulates the adrenal cortex to over-produce cortisol.
Elevated cortisol may contribute to increased gluconeogenesis, protein catabolism, insulin resistance, and immune suppression, which can manifest in various symptoms like weight gain, muscle weakness, osteoporosis, hypertension, and increased susceptibility to infections.
Why Managing Cortisol is Important
Chronic excessive cortisol exposure can have significant long-term health impacts. Studies suggest that the mortality rate of Cushing disease is estimated to be 10-11%. Successful management of Cushing disease may still leave the individual with other chronic health conditions such as diabetes, cardiovascular disease, osteoporosis, or chronic mental health conditions.
Common symptoms of Cushing’s disease may include central obesity, with fat accumulation in the abdomen, face ("moon face"), and upper back ("buffalo hump").
Skin changes, such as thinning, slow wound healing, and purple stretch marks, may also occur due to disrupted collagen production. Individuals may experience acne and altered hair growth, especially women and prepubertal children.
Muscle weakness in the limbs can create a contrast between a large abdomen and thin extremities.
Elevated cortisol may also contribute to mood disturbances including depression, anxiety, and cognitive impairment, as well as high blood pressure due to fluid retention.
Metabolic issues like insulin resistance, hyperglycemia, and hyperlipidemia are common, along with bone health problems such as osteoporosis, resulting in fragile bones and back pain.
Reproductive health may also be affected, with women facing menstrual irregularities and men experiencing decreased libido or erectile dysfunction.
Other symptoms may include increased thirst and urination, headaches, visual disturbances, and decreased immunity, which can mimic conditions like diabetes or cardiovascular disease.
Types of Medications for Cushing’s Disease
Medical management of Cushing's Disease requires careful selection and monitoring of therapies to balance efficacy and side effects, considering individual-specific factors and disease severity.
Here we’ll discuss the different classes of medications used including their mechanism of action, clinical indications, potential side effects, and monitoring requirements.
Adrenal Steroidogenesis Inhibitors
Ketoconazole, metyrapone, mitotane, etomidate, and osilodrostat are steroidogenesis inhibitors that may help manage cortisol production by blocking adrenal enzymes.
Ketoconazole is effective but can cause liver toxicity and male hypogonadism, requiring regular liver function monitoring. It may also lead to gastrointestinal issues.
Metyrapone and osilodrostat provide rapid cortisol management but can cause adrenal insufficiency, androgenic effects, hypertension, gastrointestinal upset, and hypokalemia.
Mitotane is less commonly used due to slower action and neurological side effects. It can cause gastrointestinal disturbances, CNS effects, and teratogenicity. Mitotane also accelerates the metabolism of other steroids, complicating glucocorticoid replacement.
Etomidate is used for rapid cortisol management in severe hypercortisolism cases, typically in hospitalized patients.
Monitoring for all steroidogenesis inhibitors includes watching for symptoms of adrenal insufficiency (fatigue, nausea, vomiting, hypotension, electrolyte imbalances), regular checks of blood glucose, lipid levels, and other metabolic parameters, and monitoring blood pressure, especially with metyrapone, due to hypertension risk.
Pituitary-Directed Treatments
The primary pituitary-directed treatments for Cushing's disease (CD) are cabergoline and pasireotide, which both aim to manage ACTH production in pituitary corticotroph tumors to help lower cortisol levels.
Pasireotide targets somatostatin receptors, potentially reducing cortisol and tumor size but often causes hyperglycemia, requiring careful management. Common side effects include gastrointestinal issues, hyperglycemia, gallstones, and elevated liver function tests, necessitating monitoring for glucose intolerance and metabolic disturbances.
Cabergoline, a dopamine agonist targeting D2 receptors, may help lower cortisol and tumor size but may cause impulse control problems and potential cardiac effects. Side effects include nausea, dizziness, and asthenia, with some concerns about long-term use leading to heart valve disease, though evidence is not definitive.
Glucocorticoid Receptor Antagonist
Mifepristone blocks cortisol effects, which may help manage hyperglycemia and weight gain without reducing cortisol levels.
Mifepristone can cause symptoms of cortisol insufficiency, hypokalemia, hypertension, and endometrial thickening. Monitoring response is based on clinical symptoms rather than biochemical markers due to the nature of receptor blockade.
Monitoring for adrenal insufficiency is complex, and it should only be used by experienced clinicians due to its side effects and lack of biochemical markers to monitor efficacy.
Combination Therapy
Combination therapy is often considered when monotherapy is insufficient. Common combinations include ketoconazole with metyrapone, or ketoconazole with cabergoline, to maximize cortisol management while potentially minimizing side effects. More aggressive combinations are used for severe hypercortisolism.
General Practice for Medication Selection and Monitoring
Clinicians keep the following themes in mind when selecting and monitoring an appropriate medication regimen:
Determining When to Use Medications
Medications may be used in the following situations:
Second-Line Therapy: medications are used when surgery is not possible, has failed, or when rapid cortisol management is needed. This applies to ACTH-dependent CS patients with noncurative or inoperable conditions, guided by individual preferences, CS cause, and urgency.
Primary Treatment for Ectopic ACTH Syndrome: if the tumor can't be localized, resected, or in cases of metastasis, use steroidogenesis inhibitors or glucocorticoid receptor antagonists.
Adjunctive Treatment: medications may help manage cortisol in adrenocortical carcinoma or supplement radiation therapy.
Emergency Situations: for life-threatening hypercortisolism (e.g., severe infections, cardiovascular issues, psychosis), use steroidogenesis inhibitors or glucocorticoid receptor antagonists immediately to help manage cortisol levels.
Selection Criteria for Medication
Factors such as disease severity, need for rapid cortisol management, tumor presence, comorbidities (e.g., diabetes, hypertension), individual preferences, and potential side effects influence the choice of medication.
Specific drugs may be preferred based on individual characteristics, such as gender or pregnancy plans.
Overview of Medication Monitoring and Adjustments
Regular monitoring of cortisol levels, symptoms, and comorbidities is essential. Adjustments are made based on efficacy and side effects. Annual imaging is recommended to monitor tumor growth, particularly with long-term use of steroidogenesis inhibitors or mifepristone.
Preoperative and Long-term Use
Medication may be used preoperatively to help manage severe hypercortisolism or when surgery is delayed. Long-term use is generally for individuals with persistent symptoms post-surgery or those not eligible for surgery.
Combination therapy may be necessary for chronic management.
What to Expect During Treatment
Individuals with Cushing's syndrome may begin to see a reduction in cortisol levels soon after starting medication, often within days to a few weeks. This is particularly true for steroidogenesis inhibitors, which have a rapid onset and high efficacy in managing cortisol.
Regular monitoring of cortisol levels is essential to gauge the initial response and adjust the dosage accordingly.
Long-Term Management
Individuals may need long-term, sometimes indefinite, medication use if surgery is not an option or was not fully curative. Management involves adjusting drug types and dosages to help manage cortisol and minimize side effects, with regular follow-ups for optimization.
Ketoconazole, metyrapone, and mitotane are used to inhibit adrenal steroidogenesis, potentially reducing cortisol levels and managing Cushing’s Disease symptoms. However, efficacy can vary, and treatment escape is common.
Regular monitoring of cortisol, liver function (especially with ketoconazole due to hepatotoxicity), and blood levels is essential.
Mitotane requires monitoring for neurological side effects and adrenal insufficiency. Blood pressure, electrolytes (potassium), and glucose levels should be checked due to risks like hypokalemia and hypertension.
Mifepristone requires monitoring clinical symptoms and metabolic parameters (blood glucose, weight, blood pressure) to assess treatment response. Vigilance for adrenal insufficiency symptoms, such as weakness and fatigue, is crucial. Periodic imaging may be needed to monitor for potential tumor growth, particularly in the pituitary.
Cabergoline and pasireotide require regular monitoring of cortisol and ACTH levels. Cabergoline needs blood pressure and heart function checks due to risks of hypotension and cardiac issues. Pasireotide monitoring includes blood glucose, liver function, and thyroid function due to risks of hyperglycemia, liver enzyme elevation, and hypothyroidism.
Regular imaging may be necessary to track tumor size with long-term use of these medications.
Impact on Quality of Life
Medications for Cushing's Disease can greatly enhance quality of life by helping to alleviate symptoms like fatigue, weight gain, high blood pressure, and mood disturbances. Drugs such as ketoconazole, metyrapone, mitotane, mifepristone, cabergoline, and pasireotide may help manage cortisol production or its effects, leading to symptom relief.
This can result in increased energy levels, improved weight management, better blood pressure control, and enhanced mood and cognitive function. Effective management can improve both physical and mental health, significantly boosting overall well-being.
Regular monitoring and individualized therapy adjustments are crucial to maintaining these benefits and minimizing side effects.
When to Consult Your Doctor
Individuals in recovery from Cushing’s disease may have questions regarding the efficacy of their treatments. It is important to feel comfortable reaching out to a healthcare provider with questions.
Signs That Medications Are Working
Effective management for Cushing's disease can be indicated by a noticeable reduction in symptoms such as fatigue, weight gain, high blood pressure, and mood disturbances. Additionally, laboratory tests showing normalized cortisol levels are a key marker of management success.
When to Report Side Effects
Some side effects may require immediate medical attention including severe headaches, significant changes in blood pressure, muscle weakness, unusual fatigue, hypokalemia (low potassium levels), jaundice (which may be due to liver damage from ketoconazole), or signs of adrenal insufficiency like dizziness and fainting.
It's important to promptly report these symptoms to a healthcare provider.
Adjusting Treatment Plans
Regular consultations with healthcare providers are crucial to monitor the effectiveness of the management plan and make necessary adjustments. This may involve altering dosages or switching medications to better manage symptoms, minimize side effects, and ensure optimal control of cortisol levels.
Alternative and Complementary Treatments
Management plans for Cushing’s disease may include the following:
Surgical Options
Surgery is often the first-line approach for Cushing's disease, aiming to remove the pituitary tumor responsible for excess cortisol production. Transsphenoidal resection of the ACTH-secreting tumor can effectively help normalize cortisol levels and alleviate symptoms.
Successful surgery, especially when performed by experienced surgeons, offers the best chance for long-term remission.
It is typically recommended after confirming the diagnosis and tumor localization via imaging, like MRI. The primary goals are to help restore normal cortisol levels, improve symptoms, and reduce the risk of severe complications such as cardiovascular disease and diabetes.
Radiation Therapy
Radiation therapy (RT), including external-beam radiation and stereotactic radiosurgery (SRS), is used when surgery is insufficient or tumors are aggressive.
RT can help achieve biochemical remission and control tumor growth but often leads to hypopituitarism, requiring lifelong monitoring for tumor recurrence and hormone deficiencies.
Lifestyle Modifications
Diet and lifestyle are foundational for recovery, with a focus on a healthy diet, regular exercise, good sleep, and stress management to support overall well-being and HPA axis function.
A balanced diet plays a crucial role in managing weight, blood sugar, and bone health, while regular exercise improves cardiovascular health, muscle strength, and mood.
Stress management is essential, as reducing stress helps prevent cortisol fluctuations and aids in recovery.
Ongoing medical monitoring is important for the early detection and management of complications such as hypertension, diabetes, osteoporosis, and psychological issues. Regular follow-ups are vital to ensure prompt management of emerging problems, supporting long-term health and quality of life.
[signup]
Conclusion
- Recap of Medication Options
- Adrenal Steroidogenesis Inhibitors: medications like ketoconazole, metyrapone, and osilodrostat are used to help manage cortisol production by blocking adrenal enzymes. They offer rapid cortisol management but require monitoring for side effects like liver toxicity and hypokalemia.
- Pituitary-Directed Treatments: cabergoline and pasireotide target the pituitary gland to help manage ACTH production, thus potentially lowering cortisol levels. They can be effective but may cause side effects such as hyperglycemia and potential cardiac issues.
- Glucocorticoid Receptor Antagonist: mifepristone blocks the effects of cortisol on tissues, helping to manage hyperglycemia and weight gain. It requires careful monitoring for symptoms of adrenal insufficiency and other metabolic disturbances.
- Regularly communicate with healthcare providers to monitor cortisol levels, manage side effects, report symptom changes, and adjust management plans for optimal health outcomes.
- A comprehensive management plan, including medication, lifestyle changes, and monitoring, helps manage symptoms effectively. Appropriate management improves energy, mood, and physical health, enhancing quality of life.
%201.svg){kind=logo}
