Depression and Thyroid Disease

Patient Expert

Did you know that Linda Ronstadt, Mary-Louise Parker, Oprah, Kim Cattrall and George and Barbara Bush have thyroid disease? Probably not. Thyroid problems don't make the news, at least not as often as mental health issues do. But if you believe that you have clinical depression, or have been diagnosed with clinical depression, you should make sure that your doctor rules out thyroid disease as a cause or contributing factor.

We are all taught how our brain and the nerves in our body act as an electrical control system for everything we do, but we rarely learn about how our endocrine system controls all of the biological processes in our bodies. The endocrine system consists of a series of glands scattered throughout the body. These glands include the pituitary, the pineal, the hypothalamus, the thyroid, the parathyroid, the pancreas, the testes and ovaries, the liver, the adrenal glands and a host of lesser known glands. Each of these glands release hormones into our blood that send chemical signals throughout our body to regulate all of the complex biological processes that keep us alive and functioning. We often think of ourselves as electrically operated beings, when in fact, we are one huge system of chemical factories communicating through our blood system and not our nerves.

Most of the antidepressants available today work by manipulating the levels of a specific class of hormones in our body called monoamines. These are neurotransmitters like dopamine, norepinephrine, and serotonin which exist in the synaptic cleft between the neurons in our brains. That's the connection between the electrical cells that make up the brain and the biological entity that makes its existence possible.

Today, the primary focus is on treating depression by directly managing the levels of neurotransmitters in our brains. However, what if that imbalance in neurotransmitters was specifically created by an imbalance in one of the endocrine glands, like the thyroid? It just so happens that a malfunctioning thyroid can cause depression. In most case, however, a single inexpensive pill taken once a day can often restore proper thyroid function with few if any side effects.

The thyroid is a complex organ and it controls how energetic we are, how fast our body makes proteins, and the sensitivity we have to other hormones. Thyroid problems are also more common amongst women and can be related to childbirth, radiation exposure, menopause, smoking, aging and host of environmental exposures.

One often overlooked cause of thyroid disease is a medical treatment popular from the late 30's until the early 1970's. During this period as many as 2.6 million children and adults had radium rods inserted into their nose to relieve sinus congestion and other respiratory problems. While the treatment had some positive results, it exposed the pituitary and thyroid to unacceptable levels of radium irradiation that resulted in many cases of thyroid disease. [ At a December 1993 news conference, Secretary of Energy, Hazel O'Leary, revealed that nasal radium irradiation was the single largest radiation exposure to the US population.]

Generally, a thyroid function test is part of the diagnostic procedure when evaluating a person suffering from depression. However, the thyroid is a complex organ and there are more than a dozen different tests for thyroid function. It can be a difficult diagnosis to make and one that should be performed by an endocrinologist. A thyroid may be overactive or underactive, but it is usually the under or hypoactive thyroid that causes problems with depression. The primary symptom of a hypoactive thyroid is lethargy and a lack of energy similar to that often associated with depression.

Even if your antidepressants are working it may make sense to have your thyroid checked if you are suffering from any of the symptoms associated with thyroid disease. If you are no longer depressed, but you still feel like you have less energy than anyone else, have had a child, or are going through menopause, ask your doctor to consider the detailed thyroid panel with your next blood test.