Damage to the hypothalamus after brain injury can lead to serious endocrine disorders.
These disorders cause symptoms that look similar to other types of brain injury. However, they require a unique treatment approach.
Today you will learn more about the role the hypothalamus plays in the brain plus the symptoms of hypothalamus damage after brain injury.
Functions of the Hypothalamus in the Brain
The hypothalamus is a structure that lies deep in the center of the brain. It acts as a link between the central nervous system and the endocrine system.
The endocrine system is a network of glands that release chemical messengers, also known as hormones, into the bloodstream. These hormones help the various organs throughout the body function properly.
The primary role of the hypothalamus is to keep the body in homeostasis, i.e. a balanced state necessary for survival.
To attain homeostasis, the body must maintain steady levels of certain vital functions, such as:
- Body temperature
- Blood pressure
- Digestive juices
If any of these systems become unbalanced, the body sends signals to the hypothalamus. The hypothalamus, in turn, releases hormones that will balance the body.
Some of the most important hormones released by the hypothalamus include:
- Corticotropin-releasing hormone (CRH). CRH helps the body produce cortisol, a critical stress hormone.
- Thyrotropin-releasing hormone (TRH). TRH stimulates thyroid function. The thyroid plays a crucial role in the function of many organs, such as the intestines and muscles.
- Antidiuretic hormone. ADH helps regulate water levels in the body by causing the kidneys to absorb water.
The hypothalamus is vulnerable to damage. This means after an injury, it can be difficult, if not impossible, for the brain to produce these hormones in proper amounts.
Effects of Hypothalamus Damage After Brain Injury
Traumatic brain injury can cause direct injury to the hypothalamus. The anterior hypothalamus is particularly vulnerable to injury.
In fact, according to studies, almost 60% of brain injuries result in hypothalamic problems.
Despite this relatively high number, hypothalamus damage is often overlooked during brain injury treatment. That’s why it’s important to know the signs of hypothalamus injury so you can seek the correct form of treatment.
The symptoms of hypothalamus damage after brain injury include:
Extreme body temperature changes
The hypothalamus plays a critical role in stabilizing the body’s core temperature. For example, if the body’s temperature goes above 98.6 degrees Fahrenheit, the hypothalamus will cause the body to sweat until it cools down.
However, when the hypothalamus becomes injured, it can no longer control your temperature. Therefore, you may experience frequent hot or cold flashes.
A prolonged increase in core body temperature can lead to further brain damage. That’s why it is important to seek treatment as soon as possible.
The hypothalamus instructs the adrenal glands to release adrenaline and cortisol into the bloodstream. If the hypothalamus is not functioning properly, the adrenal glands will also stop functioning. This can lead to adrenal insufficiency, which causes:
- Weight loss
- Muscle weakness
- Low blood pressure
This is a life-threatening condition if left untreated, so if you suspect you might have this, talk to your doctor immediately.
Hypothalamus damage after brain injury can also lead to low thyroid function.
The thyroid is a butterfly-shaped gland on the front of your neck. It produces several thyroid hormones that are critical for functions such as metabolism, growth, body temperature, and several others.
If the thyroid does not receive stimulation from the hypothalamus, however, it cannot produce these critical hormones. This leads to hypothyroidism, which can cause the following problems:
- Concentration and memory problems
- Unexplained weight gain
- Extreme fatigue
- Infertility and/or irregular periods
Finally, if your hypothalamus does not produce enough ADH, your body will not retain enough water. This can cause a condition known as diabetes insipidus.
Unlike other forms of diabetes after brain injury, diabetes insipidus does not affect the body’s ability to use glucose. Rather it causes symptoms such as:
- Extreme thirst
- Excessive urination
- Dry skin
- Muscle weakness
Diabetes insipidus can cause serious, life-threatening problems if left untreated. Fortunately, it can be effectively treated with vasopressin infusions.
Diagnosing Hypothalamus Damage
The best way to diagnose hypothalamic dysfunction after brain injury is by measuring heart rate variability (HRV).
To do this, a doctor will give you a Holter monitor that records heart function for 24 hours. The device is attached to your chest via electrodes, which allows you to continue with normal daily activities.
If you do not have hypothalamus damage, your heart rate will fluctuate. This indicates that the endocrine system is functioning well and keeping the body regulated.
However, if hypothalamus dysfunction is present, your heart rate will not show as many changes; it will either be consistently high or low.
That’s because there is no longer any back and forth between the body’s sympathetic and parasympathetic responses, which are controlled by the hypothalamus.
Other ways to test for hypothalamus damage include:
- Blood or saliva tests for cortisol, estrogen, and other hormone levels
- Eyeball pressure tests
Once you have been diagnosed with hypothalamus damage, your doctor will most likely start you on hormone therapy to replace your deficiencies.
Hypothalamus Damage Recovery
For most types of brain injury, the symptoms are caused by damage to the axons or to the brain cells themselves.
To treat these symptoms, patients must activate their brain’s neuroplasticity. This helps the brain rewire nerve cells and regain function.
With hypothalamus damage, however, this approach does not work, because the symptoms are caused by hormonal imbalances. Instead, treatment for hypothalamus damage involves replacing the lost hormones.
Therefore, it is critical for all brain injury patients to have their hormone function tested by an endocrinologist. Some hormones your doctor might treat you with include:
- Vasopressin, which helps the body absorb more water.
- Growth hormone, which keeps muscles and bones healthy
- Hydrocortisone to replace cortisol
- Progesterone to help with the menstrual cycle
Most of these hormones will need to be taken at the same time daily to help keep the body regulated.
Hypothalamus Brain Injury: Key Points
The hypothalamus controls many crucial bodily functions that can be lost after a brain injury. Fortunately, most of those issues can be solved with hormonal therapy.
If your brain injury symptoms do not seem to be improving from traditional therapy, ask your doctor to check your hypothalamus function. It’s possible that your problems are actually being caused by hormonal imbalances.
The sooner you can get your hypothalamus damage under control, the sooner you can get back to making progress on your recovery.
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