The endocrine system includes glands and organs that make and release hormones throughout the body. Hormones control growth, sexual development, the body’s ability to use and store energy, and how the body responds to illness. Two important parts of the endocrine system, the hypothalamus and the pituitary gland, are located in or near the brain, which means they are susceptible to damage in cases of TBI.
The hypothalamus and the pituitary gland are critical to the endocrine system and the body’s health in general because they tell all the other endocrine glands when to make hormones. The hypothalamus is the part of the brain that controls the release of hormones made by the pituitary gland, and those hormones in turn signal other glands, such as the thyroid and adrenal glands, to make and release other kinds of hormones.
If the hypothalamus or pituitary gland is damaged because of a TBI, it can cause a number of problems in the endocrine system, including hyperthermia, adrenal insufficiency, diabetes insipidus, hyponatremia, hypothyroidism, hypogonadism, growth hormone deficiency, and hyperprolactinemia.
Hyperthermia: The hypothalamus is responsible for regulating body temperature. When the hypothalamus doesn’t work properly, called hypothalamic dysfunction, body temperature can rise to dangerous or even fatal levels.
Adrenal insufficiency: The adrenal glands don’t make enough hormones, which can cause fatigue, weight loss, low blood pressure, vomiting, and dehydration. Adrenal insufficiency can be life-threatening if it’s not treated with hormone therapy.
Diabetes insipidus: The pituitary gland can’t make enough antidiuretic hormone, or ADH, which helps control the amount of water in the body. A lack of ADH can cause frequent urination and extreme thirst.
Hyponatremia: Certain hormone problems can cause an imbalance of water and salt in the body, which can lead to headache, fatigue, vomiting, confusion, and convulsions.
Hypothyroidism: The thyroid gland doesn’t make enough thyroid hormone, which can cause fatigue, constipation, weight gain, irregular menstrual periods, and a constant feeling of being cold.
Hypogonadism: Not enough sex hormones are being made. In women, this can cause menstruation to stop and a loss of body hair. In men, it can mean sexual dysfunction, breast enlargement, loss of body hair, and muscle loss.
Growth hormone deficiency: The pituitary gland doesn’t make enough growth hormone, which can cause increased fat, loss of muscle and bone, and decreased energy in adults. In children, it can cause growth problems.
Hyperprolactinemia: The pituitary gland makes too much prolactin, the hormone that starts breast milk production after childbirth. This can cause irregular menstrual periods and nipple discharge in women and erectile dysfunction in men.