Abstract

The endocrine system comprises multiple organs/glands/tissues producing various hormones. The central nervous system has receptors for multiple hormones (e.g., growth, thyroid, and sex hormones). Several hormones play an essential role in the cell development of the central nervous system and brain connectivity. Dysfunctions of the endocrine system can adversely impact the central nervous system either directly or through the consequences of the endocrine dysfunctions. This presentation reviews the neuropsychiatric manifestations of excess or deficiency of hormones produced by the hypothalamus, pituitary, thyroid, parathyroids, adrenals, pancreas, testes, and ovaries. The syndrome of inappropriate antidiuretic hormone (arginine vasopressin) secretion, observed in a variety of medical conditions (e.g., tumors and drugs), is responsible for hyponatremia. Hyponatremia causes headache, nausea, drowsiness, and disorientation.

Severe and rapidly evolving hyponatremia can lead to seizures, coma, and death. Excess growth hormone, commonly due to a pituitary adenoma and responsible for acromegaly, is associated with anxiety and depression. Excess thyroid hormones (hyperthyroidism), a medical condition caused by autoimmunity (Graves’ disease) or toxic adenoma, are responsible for irritability, nervousness, agitation, tremors, insomnia, anxiety, depression, and psychosis. Thyroid hormone deficiency (hypothyroidism), due to a variety of causes, including autoimmunity (Hashimoto’s thyroiditis), surgery, and radiation therapy, is associated with cognitive impairment, anxiety, depression, and psychosis. Excess parathyroid hormone (hyperparathyroidism), mainly caused by a parathyroid adenoma or hyperplasia and responsible for hypercalcemia, can induce cognitive impairment, insomnia, anxiety, depression, and psychosis. Parathyroid hormone deficiency (hypoparathyroidism), due to different causes such as surgery and autoimmunity and responsible for hypocalcemia, is associated with cognitive impairment, depression, and seizures. Excess cortisol (hypercortisolism), mainly due to an adrenocorticotropic-secreting pituitary adenoma (Cushing’s disease) or adrenal adenoma (Cushing’s syndrome), is causing anxiety, depression, and psychosis. Aldosterone and cortisol deficiencies (adrenal insufficiency) of peripheral or central origin can induce cognitive impairment, depression, and psychosis. Excess catecholamines, observed in a variety of medical conditions, especially a tumor of the adrenal gland (pheochromocytoma), are responsible for anxiety.

Excess insulin produced by a pancreatic tumor (insulinoma) causes hypoglycemia. Hypoglycemia can be associated with tremors, confusion, seizures, and coma. With type 1 and type 2 diabetes, disorders resulting from deficiency of insulin secretion and action, subjects may develop depression. Testosterone deficiency in men (male hypogonadism), a hereditary/congenital or acquired medical condition, is responsible for low libido, anxiety, and depression. Estrogen deficiency in women (female hypogonadism/menopause), a medical condition that can be hereditary/congenital or acquired, is associated with hot flashes, decreased sexual desire, sleep and mood disorders, learning and memory impairments, and depression. Progesterone deficiency during the luteal phase of the menstrual cycle is responsible for premenstrual syndrome (irritability, mood swings, anxiety, and depression). Most of the above neuropsychiatric manifestations can be reversed with the appropriate treatment of the endocrine dysfunctions.