Acromegaly: What Happens When Too Much Growth Hormone Is Produced

Acromegaly is a rare hormonal disorder caused by the pituitary gland producing too much growth hormone. Growth hormone is normally produced in the pituitary gland, a small gland located at the base of the brain. Growth hormone controls how tall you grow during childhood and adolescence, and it continues to affect metabolism and body composition throughout life. In acromegaly, the pituitary gland produces excessive amounts of growth hormone, usually due to a noncancerous tumor called an adenoma. The excessive growth hormone causes abnormal growth of bones and soft tissues, particularly in the hands, feet, and face. This excessive growth gives acromegaly its name, which comes from Greek words meaning “large extremities.” Acromegaly affects approximately five to ten people per million worldwide, making it a rare disorder. The disease typically develops slowly over years before symptoms are noticeable. Acromegaly most commonly develops in middle-aged adults, though it can occur at any age. In children, excessive growth hormone production causes excessive height and gigantism, whereas in adults, where growth plates have closed, it causes acromegaly with abnormal growth of hands, feet, and face. Acromegaly is often diagnosed late because the physical changes occur gradually and people may not recognize them as abnormal. Patients may be unaware of how much they have changed over years, and family members accustomed to the gradual changes may not notice them either. Early recognition and diagnosis are important because prolonged exposure to excess growth hormone causes serious complications and health problems. With proper treatment, growth hormone levels can be controlled and many complications can be prevented or reversed. However, some permanent changes from long-standing acromegaly may not resolve even after treatment successfully lowers growth hormone levels. Understanding acromegaly is important for recognizing symptoms early and obtaining appropriate treatment.

How Does Excess Growth Hormone Cause Acromegaly?

To understand acromegaly, we need to learn about growth hormone and how it normally works. Growth hormone is produced by cells in the pituitary gland called somatotroph cells. Growth hormone is released into the bloodstream and travels throughout the body where it has multiple effects. In childhood and adolescence, growth hormone stimulates linear growth, making you taller. Growth hormone also affects metabolism, bone density, muscle mass, and body fat distribution. In adults, growth hormone levels decrease but remain important for maintaining muscle mass, bone strength, and metabolism. Growth hormone is normally tightly controlled by the brain through a feedback system. The brain measures how much growth hormone is circulating and adjusts production accordingly. In acromegaly, a tumor in the pituitary gland causes excessive production of growth hormone. Most acromegaly cases are caused by a pituitary adenoma, a benign tumor that grows on the pituitary gland. The adenoma cells produce growth hormone continuously without responding to the normal feedback signals that would turn off production. This results in excessive growth hormone circulating in the blood. About ninety-five percent of acromegaly cases are caused by a pituitary adenoma. In rare cases, acromegaly is caused by excessive growth hormone-releasing hormone, or GHRH, produced by tumors in other parts of the body like the pancreas or lungs. These ectopic tumors stimulate the pituitary to produce excessive growth hormone. The excessive growth hormone causes abnormal effects throughout the body. In bones, growth hormone stimulates osteoblasts, which are cells that build bone. In the skull, excessive bone growth causes the forehead to protrude, the jawbone to enlarge, and the spacing between teeth to increase. In the hands and feet, bones become thicker and longer. In soft tissues, growth hormone stimulates growth of muscle and other tissues. The skin thickens and becomes oily. Organs like the heart, lungs, and kidneys enlarge. The tongue enlarges. Cartilage in joints thickens, causing joint problems. The prolonged exposure to excessive growth hormone over years causes serious health complications. Early recognition and treatment to lower growth hormone levels is important to prevent these complications.

What Are the Main Symptoms and Signs of Acromegaly?

Acromegaly causes a wide variety of physical, metabolic, and systemic changes due to the effects of excessive growth hormone on body tissues and metabolism. The physical changes are usually the first symptoms people notice, though these develop gradually over months and years. Enlargement of hands and feet is one of the most characteristic features. Hands become larger and broader, with thicker fingers. Feet increase in size. People may notice they need progressively larger shoe sizes over time. Enlargement of facial features is very noticeable. The forehead becomes prominent and protruding. The lower jaw becomes enlarged and protrudes forward, causing an underbite called prognathism. The nose becomes larger and broader. Lips become thicker. The spacing between the front teeth increases. The tongue enlarges, a condition called macroglossia. These changes happen gradually, and patients often don’t realize how much their appearance has changed. Family members accustomed to the gradual changes may not notice them either. Enlargement of other body parts occurs. The skull becomes thicker. The brow ridge becomes more prominent. Skin becomes thick, oily, and rough-textured. Skin tags may develop. Excessive sweating is very common. Patients may sweat profusely even without exertion. Hyperhidrosis, or excessive sweating, is very characteristic of acromegaly. Voice deepens due to enlargement of the vocal cords and larynx. Sleep apnea is common. Enlargement of soft tissues in the throat can obstruct breathing during sleep. Patients may snore loudly and stop breathing briefly during sleep. Sleep apnea contributes to fatigue and daytime sleepiness. Joint pain and arthritis develop due to abnormal cartilage growth and joint stress. Hands, knees, hips, and spine are commonly affected. Arthropathy, or joint disease, can become severely limiting. Muscle weakness may occur despite muscle enlargement. Paradoxical weakness can develop as acromegaly progresses. Carpal tunnel syndrome is very common, causing numbness and tingling in the hands. The enlarged carpal tunnel compresses the median nerve. Headaches are common and may be severe. The pituitary tumor itself can cause headaches. Visual disturbances may occur from the tumor pressing on the optic nerves. Bitemporal hemianopsia, loss of outer visual fields, occurs if the tumor extends upward into the optic chiasm. Erectile dysfunction occurs in men. Low libido occurs in both men and women. These result from growth hormone excess and sometimes from reduced gonadal hormone production. Menstrual irregularities occur in women. Galactorrhea, or inappropriate breast milk production, may occur from elevated prolactin. Fatigue and weakness are very common. These result from metabolic changes and complications like diabetes and sleep apnea. The fatigue can be profoundly limiting and affect quality of life.

How is Acromegaly Detected and Diagnosed?

Acromegaly is often diagnosed late because the physical changes occur gradually over years and people adapt to the gradual changes. Recognition of the characteristic physical features is important for suspecting acromegaly and ordering appropriate tests. Clinical examination reveals the characteristic facial features, enlarged hands and feet, and other physical signs of acromegaly. Comparison of old and recent photographs often shows the progressive changes in appearance. Old photos are helpful for documenting the gradual development of acromegaly. Growth hormone measurement is the key diagnostic test. A fasting growth hormone level is drawn. In acromegaly, growth hormone levels are elevated. However, a single elevated growth hormone level is not diagnostic because growth hormone pulses with variable levels throughout the day. Insulin-like growth factor 1, or IGF-1, is a more specific test for acromegaly. IGF-1 is a hormone produced by the liver in response to growth hormone. IGF-1 has a relatively constant level in blood and directly correlates with the average growth hormone level. IGF-1 is elevated in acromegaly. An elevated IGF-1 is highly suggestive of acromegaly. Growth hormone suppression test is done to confirm acromegaly. After oral glucose administration, growth hormone should suppress to low levels. In acromegaly, growth hormone fails to suppress to normal levels. Failure of growth hormone to suppress after glucose is diagnostic of acromegaly. Pituitary MRI is done to identify the adenoma. The tumor can usually be visualized on MRI. The size and location of the adenoma affect treatment planning. Vision assessment is important to check for visual field defects from tumor compression of optic nerves. Formal visual field testing helps determine if the tumor is compressing the optic chiasm. Other hormone testing may be done to check for other hormone abnormalities caused by the adenoma. Prolactin levels are often elevated. Thyroid function is checked. Cortisol and ACTH levels are assessed. Gonadal hormone levels may be low. Assessment of complications is important. Blood glucose is checked for diabetes. Blood pressure is measured. Echocardiography assesses heart enlargement and function. Sleep study may be ordered to evaluate sleep apnea. Metabolic panel checks kidney and liver function. Early diagnosis allows treatment to be started before serious complications develop.

What Health Complications Do People with Acromegaly Face?

People with acromegaly face serious health complications due to the prolonged effects of excessive growth hormone on body systems. Type 2 diabetes develops in about forty percent of people with acromegaly. Growth hormone is antagonistic to insulin, meaning it opposes insulin’s effects on blood sugar. The excessive growth hormone causes insulin resistance and diabetes. Diabetes increases risk of heart disease, kidney disease, and other complications. Blood pressure elevation occurs in about fifty percent of people with acromegaly. Hypertension from acromegaly results from both the direct effects of growth hormone and from associated metabolic abnormalities. Elevated blood pressure increases risk of heart attack and stroke. Cardiac disease is one of the major complications of acromegaly. The heart becomes enlarged, a condition called cardiomegaly. The enlarged heart muscle becomes stiff and cannot function properly. Cardiomyopathy, or heart muscle disease, develops. Coronary artery disease accelerates due to combined effects of growth hormone excess, diabetes, and hypertension. Heart failure can develop from the enlarged, weakened heart. Cardiac arrhythmias develop from the enlarged heart. Sudden cardiac death can occur from severe arrhythmias or hemodynamic compromise. Heart disease is a major cause of death in acromegaly. Sleep apnea affects breathing during sleep. Soft tissue enlargement in the throat obstructs airflow. Oxygen levels drop during sleep apnea episodes. Chronic sleep deprivation from interrupted sleep causes daytime fatigue and mental cloudiness. Sleep apnea contributes to hypertension and cardiac problems. Respiratory failure can occur in severe sleep apnea. Osteoarthritis develops from the abnormal cartilage growth and accelerated joint degeneration. Progressive joint pain and dysfunction limit mobility. Joint replacement may become necessary. Spinal problems develop from vertebral changes. Kyphosis, or excessive forward curvature, can develop. Spinal stenosis can compress spinal nerves. Thyroid disease occurs in about twenty percent of people with acromegaly. Goiter, or thyroid enlargement, develops. Thyroid cancer risk is increased. Malignant neoplasms have increased incidence in acromegaly. Colorectal cancer, thyroid cancer, and other cancers occur more frequently. Regular cancer screening is important. Visual field defects develop if the pituitary tumor compresses the optic nerves. Bitemporal hemianopsia, loss of outer visual fields, is characteristic. Vision may deteriorate if not treated. Pituitary dysfunction may develop. If the tumor damages the normal pituitary tissue, deficiency of other pituitary hormones can occur. Hypothyroidism, adrenal insufficiency, and gonadal hormone deficiency can develop. Hypopituitarism, deficiency of multiple pituitary hormones, may occur. Reproductive problems including infertility can result from gonadal hormone deficiency. Mortality from untreated acromegaly is increased. Cardiovascular complications are the leading cause of excess mortality. Prompt diagnosis and treatment significantly improves outcomes and reduces complications.

What Treatments Help People with Acromegaly?

Treatment for acromegaly aims to lower growth hormone levels, normalize IGF-1 levels, and shrink or remove the pituitary tumor. There is no cure for acromegaly once it develops, but appropriate treatment can control the disease and prevent or halt complications. Surgery is often the first-line treatment. Transsphenoidal surgery, where the tumor is removed through an opening in the sphenoid bone at the base of the skull, is the standard surgical approach. A neurosurgeon accesses the pituitary gland through the nose and removes the adenoma. Surgery can be curative if the entire tumor is removed and growth hormone levels normalize. Success rate depends on tumor size and surgeon expertise. Smaller, noninvasive tumors have better surgical outcomes. Larger invasive tumors may not be completely removable. Medical therapy is used if surgery is not feasible, is unsuccessful, or is declined. Somatostatin analogs are medications that inhibit growth hormone secretion. Octreotide and lanreotide are long-acting somatostatin analogs given by injection. These medications suppress growth hormone production effectively. IGF-1 levels normalize in most patients. However, these medications are expensive and require repeated injections. Growth hormone receptor antagonist pegvisomant blocks the effects of growth hormone on tissues. This medication effectively normalizes IGF-1 levels and controls acromegaly symptoms. Pegvisomant is given by injection. Dopamine agonists including bromocriptine can suppress growth hormone in some cases. These are oral medications that may help control disease, particularly in patients with prolactin-secreting tumors. Radiotherapy may be used if surgery and medical therapy are unsuccessful. Conventional radiotherapy involves multiple sessions of radiation directed at the pituitary. Gamma knife stereotactic radiotherapy delivers focused high-dose radiation in fewer sessions. Radiotherapy can lower growth hormone levels but takes weeks to months for effects to be apparent. Combination therapy using multiple medications from different classes may be necessary for optimal control. For example, a somatostatin analog combined with pegvisomant or a dopamine agonist may achieve better results than single-agent therapy. Management of complications is important. Diabetes is treated with antidiabetic medications and lifestyle modifications. Hypertension is managed with antihypertensive medications. Cardiac disease is managed with appropriate cardiac medications. Sleep apnea is treated with continuous positive airway pressure, or CPAP. Joint disease is managed with physical therapy and analgesics. Regular monitoring of growth hormone and IGF-1 levels guides treatment adjustments. Target is usually to normalize IGF-1 levels for age and gender. Growth hormone levels should be suppressed to less than one nanogram per milliliter after an oral glucose load. Monitoring for complications including diabetes, hypertension, and cardiac disease is important. Treatment success is measured by normalization of IGF-1, suppression of growth hormone, tumor shrinkage or removal, resolution of symptoms, and prevention of complications.

Living with Acromegaly

Living with acromegaly is challenging due to the physical changes, metabolic complications, and need for ongoing medical management. For people newly diagnosed with acromegaly, the diagnosis can be devastating. Learning that a pituitary tumor has caused permanent physical changes is difficult. However, understanding that the disease can be controlled with treatment offers hope. Patient education about acromegaly, treatment options, and expected outcomes helps people understand their condition and participate in decision-making. Physical appearance changes affect body image and self-esteem. The progressive enlargement of facial features, hands, and feet can cause embarrassment and social distress. People may feel they are unrecognizable compared to their younger selves. Accepting the physical changes while pursuing treatment is an important emotional process. Psychological support including counseling helps address emotional impacts. Work and social adjustments may be necessary. Coworkers and acquaintances may not recognize the person’s changing appearance and may make comments or ask questions. Explaining acromegaly to people who knew you before the changes develops is sometimes necessary. Social withdrawal may occur if the person is embarrassed by appearance changes. Maintaining relationships and social connections is important for mental health. Dating and romantic relationships may be affected. People may feel less attractive due to physical changes. Communication with partners about the condition helps maintain relationships. Sexual dysfunction from the disease and hormonal changes affects intimate relationships. Medical management requires regular doctor visits, blood tests, and imaging studies. Medications require careful adherence for optimal control. Treatment side effects require management. If surgery is chosen, recovery from transsphenoidal surgery takes several weeks. Time off work may be necessary. Post-operative monitoring ensures successful surgery and growth hormone control. Diabetes management becomes a significant part of daily life for those who develop diabetes. Regular blood glucose monitoring, dietary modifications, and possibly insulin or other medications are necessary. Hypertension management requires blood pressure monitoring and antihypertensive medications. Dietary modifications including sodium restriction help manage blood pressure. Cardiac monitoring including echocardiograms and EKGs assess heart function. Medication compliance for cardiac health is important. Sleep apnea management with CPAP therapy helps improve sleep quality and reduces fatigue. Regular CPAP use is necessary for effectiveness. Adjusting to sleeping with CPAP takes time for many people. Joint pain and arthritis require pain management and physical therapy. Range-of-motion exercises help maintain mobility. Activity modifications prevent excessive joint stress. Osteoarthritis may progressively worsen requiring eventual joint replacement. Growth hormone suppression may not reverse some permanent changes. Large hands and feet, facial features, and arthritis may remain despite successful treatment. Accepting permanent changes while acknowledging successful disease control helps optimize quality of life. Mental health challenges including depression and anxiety are common. Living with a chronic disease affecting appearance and causing multiple complications is emotionally challenging. Support groups for people with acromegaly provide community and practical advice. Counseling helps address emotional impacts. With appropriate treatment, blood sugar control, blood pressure management, cardiac monitoring, sleep apnea treatment, pain management, and psychological support, many people with acromegaly can stabilize their disease, prevent further complications, and maintain quality of life despite the permanent physical changes caused by prolonged excessive growth hormone exposure.

Frequently Asked Questions About Acromegaly

FAQ 1: Is acromegaly hereditary and does it run in families? Most cases of acromegaly are not hereditary. Acromegaly is caused by a pituitary adenoma that develops spontaneously during a person’s lifetime. The adenoma is not inherited. However, in rare cases, acromegaly can be part of hereditary syndromes. Multiple Endocrine Neoplasia type 1, or MEN1, is a hereditary condition where people develop multiple tumors including pituitary adenomas. People with MEN1 may develop growth hormone-secreting adenomas causing acromegaly. Carney complex is another rare hereditary syndrome that includes acromegaly. If you have acromegaly and a family history of adenomas or endocrine tumors, genetic testing for hereditary syndromes may be appropriate. Genetic counseling can help determine if genetic testing is recommended. Most family members of people with sporadic acromegaly do not have increased risk of developing acromegaly.

FAQ 2: Can acromegaly be cured? Acromegaly can be cured if the pituitary adenoma is completely removed surgically and growth hormone levels normalize. Surgical cure rates are highest for small, noninvasive tumors, with success rates of ninety percent or higher. For larger or invasive tumors, complete removal may not be possible, and cure is less likely. Medical therapy cannot cure acromegaly but can control growth hormone levels. With medication, growth hormone and IGF-1 can be suppressed to normal levels, achieving biochemical remission. However, if medication is stopped, growth hormone levels typically rise again. Radiotherapy can eventually lower growth hormone levels but is less likely to achieve complete cure than surgery. Many patients require long-term medical therapy to maintain growth hormone control. The earlier acromegaly is diagnosed and treated, the better the chance of cure or excellent disease control.

FAQ 3: How quickly does acromegaly develop and progress? Acromegaly develops and progresses slowly over years or even decades. The gradual development makes recognition difficult. Patients may not notice how much they have changed, and family members accustomed to the gradual changes may not notice them either. The adenoma typically grows very slowly. Most pituitary adenomas remain stable in size over many years. However, some tumors grow more aggressively. Without treatment, acromegaly continues to progress with worsening growth hormone levels and development of complications. With treatment, disease can be stabilized or reversed. Growth hormone levels typically drop within days to weeks of starting medical therapy or after successful surgery. Physical changes resolve more slowly. Soft tissue swelling may improve relatively quickly. Bone changes and some facial features are more permanent and may not fully resolve even after growth hormone normalization. Joint damage may be irreversible if not treated before damage becomes severe.

FAQ 4: What is the life expectancy for someone with acromegaly? Life expectancy is reduced in people with untreated acromegaly. The average survival without treatment is shorter than the general population due to complications including cardiovascular disease, diabetes, and cancer. With appropriate treatment that controls growth hormone levels, life expectancy improves significantly. Studies show that people with well-controlled acromegaly have survival approaching that of the general population. The key to good outcomes is early diagnosis, prompt treatment, and long-term management of complications including diabetes, hypertension, and cardiac disease. Cardiovascular complications are the leading cause of excess mortality in acromegaly. With proper treatment and management of these complications, survival and quality of life improve substantially.

FAQ 5: Are there new treatments being developed for acromegaly? Yes, there is ongoing research into new treatments for acromegaly. New somatostatin analogs with potentially better effects and fewer side effects are in development. New growth hormone receptor antagonists are being studied. Gene therapy approaches to treat the pituitary adenoma are being researched. Approaches to enhance apoptosis, or cell death, of adenoma cells are being studied. Understanding of the genetic mutations that cause adenoma growth is leading to targeted therapies. Clinical trials of new medications continue. Improved surgical techniques and radiotherapy approaches are being refined. As new treatments are developed and studied, outcomes for people with acromegaly will continue to improve.

References and Further Reading

For more information about Acromegaly, you can visit several trusted and authoritative sources that provide detailed information for patients and families dealing with this rare endocrine disorder. The World Health Organization at WHO.int provides comprehensive information about endocrine disorders and rare hormonal diseases including acromegaly. The Pituitary Foundation at PituitaryFoundation.org offers excellent patient education, family resources, support communities, information about treatments and research, and updates about new clinical trials and developments in acromegaly care. MedlinePlus, a service of the National Library of Medicine at MedlinePlus.gov, has detailed medical information about Acromegaly written in language that patients and families can easily understand without specialized medical knowledge. The National Institutes of Health at NIH.gov provides scientific information about acromegaly research, ongoing clinical trials seeking participants, and the latest discoveries being made by scientists studying pituitary disease and growth hormone regulation. The American Pituitary Society at PituitaryOnline.org provides resources for patients with pituitary disorders including acromegaly, information about specialists, and support for finding appropriate medical care. The five main reference links are: 1) WHO.int – Endocrine Disorders, 2) Pituitary Foundation, 3) MedlinePlus – Acromegaly, 4) National Institutes of Health, and 5) American Pituitary Society.

Disclaimer

This article adapts publicly available information from WHO’s Acromegaly and endocrine disorder information pages. This content is for informational and educational purposes only and does not constitute medical advice. ObserverVoice.com is a news and information platform — not a healthcare provider. If you or someone you know has been diagnosed with Acromegaly or shows signs of this condition including enlargement of hands and feet, facial feature changes, sleep apnea, excessive sweating, joint pain, or headaches with vision changes, please consult immediately with qualified healthcare professionals, endocrinologists, and pituitary specialists for proper diagnosis including growth hormone and IGF-1 testing, pituitary MRI, and appropriate treatment planning with surgery, medications, or other therapies. For more information, visit WHO.int and ObserverVoice.com.