What is growth hormone?
Growth hormone is produced from the pituitary gland located in the base of our brain. The main purpose of growth hormone is to fuel childhood growth and help to maintain tissues and organs. As we grow older, the pituitary gland gradually reduces the amount of growth hormone it produces. This natural slowdown in the release of growth hormone affects humans regarding the changes linked to aging, and decreases muscle and bone mass.
Even after we have stopped growing, adults will still need some amount of growth hormone in our system. Growth hormone is a protein that is made by our pituitary gland and is released into the blood. Growth hormone plays a vital role in the growth and maintenance of healthy muscle, how our bodies collect fat, the ratio of high density to low density lipoproteins in our cholesterol levels and bone density. Growth hormone also plays a vital role in maintaining regular brain functions.
What are the symptoms of low levels of growth hormone, or growth hormone deficiency?
- High levels of body fat, especially around the waits
- You may have anxiety and depression
- A decreased libido (sexual function and interest)
- You may become easily fatigued
- You may feel isolated from other peers
- Unable to tolerate heat or cold
- Very lean body mass and difficulty in growing muscles.
- Less strength, stamina and ability to exercise
- Reduced bone density, or history of frequent bone fractures
- Abnormal cholesterol levels
In adults with growth hormone deficiency, patients may have higher than normal levels of low density lipoproteins in comparison to their high density lipoproteins. Patients also tend to have higher triglyceride levels. A high triglycerides level in the blood contributes to block blood vessels that lead to heart attacks.
What are the common causes and risk factors for adult growth hormone deficiency?
A reduced or lack of growth hormone is most commonly caused by damage to the pituitary gland or the hypothalamus, a part of the brain that controls the pituitary gland. Damage is commonly caused by a tumor, or a history of surgery that has been done previously that has caused damage to the gland, or problems with the blood supply to the pituitary gland. Lack of growth hormone can happen anytime either during childhood or in adulthood.
How do we diagnose?
Your doctor will obtain a complete medical history, and previous surgical history related to the pituitary gland. Your doctor will investigate via blood investigations to see growth hormone levels in the body. Other common investigations that are done are MRI (Magnetic resonance imaging) to rule out tumors of the brain prior to initiation of therapy. This allows the doctor to diagnose and treat accordingly if a tumor is present.
Is there any available treatment?
Once a diagnosis of growth hormone deficiency has been confirmed, with a normal MRI of the brain and a laboratory investigation that shows a low level in growth hormone, your doctor will prescribe a daily dose of growth hormone. The hormones are injected to the patient’s body, and recurrent tests will be performed every 2-3 months to monitor the levels of growth hormone and to adjust the dosage that is injected to the patients.
The common side effect of too high levels of growth hormones in the bloodstream includes muscle or joint pain, swelling, pain or numbness in the hands. If these symptoms appear, your doctor will perform blood tests and lower the amount of growth hormone given.
If the cause of the deficiency of growth hormone is due to a pituitary tumor, your doctor will monitor the tumor with recurrent MRIs.
Lastly, routine blood cholesterol and a bone density examination will be performed and the levels will be monitored. With the correct dosage of treatment, generally patients will show signs of improvement and a higher quality of life.
When do we avoid treating growth hormone deficiency?
Growth hormone therapy should be avoided to patients who have active cancer or tumors. It also should be avoided for patients that are ill as a result of complications from an open heart or abdominal surgery, patients that have multiple injuries following an accident, or patients that have breathing difficulties.
Taking growth hormone can affect the way the body uses insulin, so it is important for anyone who has diabetes to keep their doctors informed and to be vigilant about monitoring blood sugar levels.