It is easy to think of weight gain simply as the result of eating habits or lack of exercise. However, if your face becomes rounder, fat accumulates around the abdomen and the back of the neck while the arms and legs become thinner, and bruises and purple stretch marks appear easily, you should also consider the possibility of a hormonal disorder such as Cushing's syndrome, not just simple weight gain.
Cushing Syndrome Guide: Causes, Symptoms, Cortisol Testing, and Treatment
Cushing's syndrome is a hormonal disorder that occurs when the body is exposed to excessive cortisol for a long period. Although changes in appearance can be noticeable, step-by-step testing is important because it can be confused with obesity, metabolic syndrome, depression or anxiety, polycystic ovary syndrome, and other conditions.
Cushing's syndrome refers to a state in which cortisol in the body remains excessively high for a long time. Cortisol is a hormone produced by the adrenal glands and is involved in maintaining blood pressure, controlling blood sugar, regulating inflammatory responses, and energy metabolism. It is an essential hormone, but if high levels continue for a long time, it can affect the whole body.
Cushing's syndrome arises in two broad ways. One is exogenous Cushing's syndrome, caused by steroid medications used for treatment. The other is endogenous Cushing's syndrome, in which cortisol becomes excessive because of a problem within the body, such as a pituitary tumor, adrenal tumor, or ectopic tumor.
The important point is that you should not decide on your own that you have Cushing's syndrome, stop medication, or choose a treatment direction by yourself. In particular, stopping steroids that have been taken for a long time can cause adrenal insufficiency and serious whole-body symptoms, so a tapering plan must be made with the prescribing doctor.
Basic Information on Cushing's Syndrome
The Key to Understanding Cushing's Syndrome: What Is Cortisol?
Cortisol is often called the stress hormone. In stressful situations, it helps the body cope by regulating blood pressure and blood sugar and by influencing inflammatory responses and energy use. The problem is not cortisol “rising when needed,” but rather “remaining high for a long time.”
When cortisol stays high, the muscles, skin, bones, blood vessels, and blood sugar control systems are affected. Therefore, Cushing's syndrome is not only an issue of appearance changes; it can lead to systemic complications such as high blood pressure, diabetes, osteoporosis, infection risk, blood clots, and mood changes.
Caution: The information below is health information intended to help you understand the condition. If you have actual symptoms or are taking steroid medications, it is safer to consult an endocrinologist or the prescribing doctor rather than self-diagnosing.
Main Causes of Cushing's Syndrome
| Category | Cause | Description | Key point to check |
|---|---|---|---|
| Exogenous | Long-term use of steroid medications | Long-term use of glucocorticoids for asthma, rheumatic diseases, autoimmune diseases, skin diseases, immunosuppression after organ transplantation, and other reasons | Check history of oral medications, injections, inhalers, and topical skin preparations |
| Endogenous | Pituitary tumor, Cushing's disease | A pituitary tumor secretes excessive ACTH, stimulating both adrenal glands to produce cortisol | Evaluated with normal or elevated ACTH, pituitary MRI, and other tests |
| Endogenous | Adrenal tumor | An adrenal adenoma or cancer itself produces excessive cortisol | Evaluated with decreased ACTH, adrenal CT, and other tests |
| Endogenous | Ectopic ACTH-secreting tumor | A tumor in an organ outside the pituitary gland, such as the lung, pancreas, or thymus, secretes ACTH and stimulates the adrenal glands | Elevated ACTH; the location of the causative tumor must be identified |
The Difference Between Cushing's Syndrome and Cushing's Disease
Cushing's syndrome
This is a broad term for any condition in which excess cortisol persists for a long time. Whether the cause is steroid medication, a pituitary tumor, or an adrenal tumor, all can be included under Cushing's syndrome.
Cushing's disease
This refers specifically to cases of Cushing's syndrome caused by a pituitary tumor that secretes too much ACTH. In other words, Cushing's disease is one type of Cushing's syndrome.
Key Symptoms That Are Visibly Noticeable
1. Central obesity
Fat may concentrate around the abdomen, chest, and neck, while the arms and legs may become relatively thin. This body-shape change, different from typical weight gain, can be a clue.
2. Round face and fat behind the neck
A moon face, in which the face looks round and reddish, and a buffalo hump, in which fat accumulates between the back of the neck and the shoulders, may appear.
3. Skin changes
The skin may become thin and bruise easily, and wide, purplish stretch marks may develop on the abdomen, thighs, chest, buttocks, and other areas.
4. Decreased muscle strength and fatigue
Weakness in the thigh and arm muscles can make it difficult to climb stairs, get up from a chair, or lift objects.
Checking Whole-Body Symptoms and Complications
| Area | Possible changes | Why it matters |
|---|---|---|
| Blood pressure | High blood pressure | May be linked to the risk of cardiovascular disease |
| Blood sugar | High blood sugar, insulin resistance, diabetes | May be mistaken for a metabolic disorder along with weight gain |
| Bones | Decreased bone density, osteoporosis, fracture risk | Fracture risk may need to be assessed even at a young age |
| Infections | More frequent infections | Excess cortisol can affect immune responses |
| Mental health | Depressed mood, anxiety, reduced concentration, memory decline | Should be viewed together with physical symptoms, not only as simple stress or depression |
| Women's health | Irregular menstruation, amenorrhea, hirsutism | Differentiation from conditions such as polycystic ovary syndrome may be needed |
| Men's health | Decreased libido, reduced reproductive function | May be related to broader hormonal changes |
Signs That Should Be Viewed Differently From Simple Obesity
Rather than weight gain alone, “distribution and accompanying symptoms” are important.
If fat accumulates in the abdomen and behind the neck while the arms and legs become thinner, and purple stretch marks, bruising, decreased muscle strength, high blood pressure, and high blood sugar occur together, it is difficult to explain this as simple weight gain alone. In particular, if you have a history of long-term steroid medication use, you must tell your doctor during consultation.
Diagnostic Process: Why Symptoms Alone Do Not Confirm It
Cushing's syndrome can have noticeable outward symptoms, but it is not diagnosed based on symptoms alone. This is because it overlaps in many ways with obesity, depression and anxiety, diabetes, high blood pressure, polycystic ovary syndrome, and metabolic syndrome. Therefore, medication history is checked first, and tests are used to confirm whether cortisol excess is actually present.
| Step | Test | Purpose | Interpretation point |
|---|---|---|---|
| Step 1 | Check steroid use history | Exclude or confirm an exogenous cause | It may be necessary to check not only oral medicines but also injections, inhalers, ointments, and ingredients in herbal medicines or supplements |
| Step 1 | 24-hour urinary free cortisol | Check the amount of cortisol excreted over one day | Repeated measurements may usually be needed |
| Step 1 | Late-night salivary cortisol | Check whether cortisol normally falls at night | In Cushing's syndrome, cortisol may remain high even at night |
| Step 1 | Low-dose dexamethasone suppression test | Check whether cortisol is suppressed after dexamethasone administration | If normal, cortisol falls; if it is not suppressed, further evaluation is needed |
| Step 2 | ACTH test | Distinguish whether the cause is adrenal or ACTH-dependent | If ACTH is low, an adrenal cause is considered; if normal or high, a pituitary or ectopic cause is considered |
| Step 3 | Imaging tests such as MRI and CT | Identify the location of a pituitary, adrenal, or ectopic tumor | Test results and hormone levels must be interpreted together |
If the Testing Flow Is Organized in Order
- First, medications and injection history are checked.
Steroid medications are known as the most common cause of Cushing's syndrome. In addition to oral medicines, joint injections, inhalers, and skin ointments may also need to be checked. - Confirm whether cortisol is actually excessive.
Depending on the patient's situation, tests such as 24-hour urinary free cortisol, late-night salivary cortisol, or the low-dose dexamethasone suppression test are performed. - It is not concluded from a single test.
Cortisol can be affected by stress, sleep, medications, alcohol, and disease status. Repeated tests and combinations of different tests are often needed. - ACTH levels help divide the likely cause.
If ACTH is low, doctors look for direct overproduction of cortisol by the adrenal glands. If ACTH is normal or high, pituitary or ectopic ACTH secretion is suspected. - Imaging tests are used to find the causative site.
Pituitary MRI, adrenal CT, and chest or abdominal imaging are used to check the location and size of tumors. More detailed tests may be added if needed.
Treatment Process: It Depends on the Cause
| Cause | Treatment direction | Key caution |
|---|---|---|
| Steroid medications | Gradual tapering under a specialist's guidance within the range in which the original disease remains controlled | Abrupt discontinuation is prohibited because of the risk of adrenal insufficiency |
| Pituitary tumor, Cushing's disease | Transsphenoidal removal of the pituitary tumor is considered as first-line treatment | Follow-up with an experienced pituitary surgery team and endocrinology is important |
| Adrenal tumor | Surgical removal of the causative adrenal lesion is considered | Temporary steroid replacement after surgery and evaluation of adrenal function recovery may be needed |
| Ectopic ACTH tumor | Treatment tailored to the cause, such as removal of the causative tumor, chemotherapy, radiation therapy, or medication | Identifying the tumor location and evaluating overall condition are important |
| When surgery is difficult or the condition recurs | Individually determined options such as medications to reduce cortisol production, radiation therapy, repeat surgery, or bilateral adrenalectomy | Treatment effects and side effects must be checked regularly |
Caution about stopping steroid medications: Even if Cushing's syndrome is suspected, abruptly stopping steroids you are taking can be dangerous. Steroids used for a long time can suppress the body's adrenal function, so tapering must be done according to the prescribing doctor's plan.
Why Management Is Needed Even After Treatment
Cushing's syndrome may improve once the cause is removed, but not all symptoms disappear immediately after treatment. Weight, muscle strength, blood pressure, blood sugar, bone density, skin changes, and mood changes may take time to recover. In particular, after surgery, cortisol levels can drop sharply, so temporary steroid replacement and regular tests may be needed.
Blood pressure and blood sugar management
High blood pressure and high blood sugar may need management for a certain period even after treatment. Medication adjustment and lifestyle management are carried out together.
Checking bone density
Excess cortisol can affect bone health. If there is a risk of osteoporosis or fractures, bone density testing and treatment are needed.
Recovery of muscle strength
Weakness in the muscles around the thighs and shoulders may recover slowly. Stepwise exercise discussed with the medical team is safer than strenuous exercise.
Monitoring for recurrence
If the cause is a tumor, hormone tests and imaging tests may be needed to check for recurrence.
When to Consult a Hospital
It is advisable to consider medical care if the following changes appear together.
- If the face suddenly becomes round and weight increases mainly around the abdomen
- If the arms and legs become thinner while fat accumulates in the abdomen, chest, and back of the neck
- If wide, purplish stretch marks appear
- If you bruise easily and wounds heal slowly
- If high blood pressure or high blood sugar newly appears or becomes difficult to control
- If symptoms suggestive of Cushing's syndrome develop while you are using steroid medications for a long time
- If decreased muscle strength, fatigue, depressed mood, sleep problems, and similar issues worsen together
Frequently Asked Questions
Q. Is Cushing's syndrome a disease that makes you gain weight?
A. It is difficult to view it simply as a disease that causes weight gain. It is an endocrine disorder in which excess cortisol can affect fat distribution, muscles, skin, blood pressure, blood sugar, and bone health.
Q. Are Cushing's syndrome and Cushing's disease the same thing?
A. Strictly speaking, they are different. Cushing's syndrome refers to the overall state of excess cortisol, while Cushing's disease means cases caused by a pituitary ACTH-secreting tumor.
Q. Can steroid ointments or injections also be a cause?
A. It is possible. The common cause is long-term, high-dose systemic steroid use, but injections, inhalers, and topical skin preparations can also have an effect depending on the amount used and the duration. You should tell your doctor about all medications you have used.
Q. Is Cushing's syndrome diagnosed with a single blood test?
A. Usually, it is not concluded from a single test. Among tests such as 24-hour urine, late-night saliva, and the dexamethasone suppression test, those suited to the patient's situation are performed, and repeated tests and cause-differentiating tests are done if needed.
Q. Can it get completely better with treatment?
A. Treatment effects vary depending on the cause. If medication is the cause, safe tapering is key; if a tumor is the cause, surgery may be considered as first-line treatment. Even after treatment, blood pressure, blood sugar, bone density, and recurrence must be checked over the long term.
Q. If Cushing's syndrome is suspected, which hospital department should I visit?
A. Because cortisol and ACTH evaluation is needed, endocrinology care is appropriate. Depending on the cause, coordinated care with neurosurgery, surgery, medical oncology, and radiology may be needed.
Closing
Cushing's syndrome may look outwardly like weight gain or facial changes, but in reality it is an endocrine disorder in which excess cortisol affects the whole body. If central obesity, a round face, fat behind the neck, purple stretch marks, bruising, decreased muscle strength, and high blood pressure or high blood sugar appear together, it is better not to dismiss it as simple obesity.
The most important thing is to accurately distinguish the cause. The treatment direction differs completely depending on whether it is due to steroid medication or to a pituitary, adrenal, or ectopic tumor. In particular, if you are taking steroids, avoid stopping them on your own, and it is safer to organize your symptoms and medication history and consult medical professionals.