Sleep Apnea and Thyroid Health - Fighting the Fatigue

By Admin

While gold standard treatments such as PAP therapy are highly effective in reducing or eliminating the symptoms of sleep apnea, no treatment is 100 percent in its outcomes. Even when treated, sleep apnea can still cause recurrent episodes of apnea or hypopnea during sleep, resulting in low blood-oxygen levels (hypoxemia) or high amounts of carbon dioxide (hypercapnia) when airflow is disrupted. Arousals can still occur as well, causing fragmented sleep and insufficient rest. In some cases, these symptoms are directly related to problems of the thyroid, the gland responsible for many of the body’s metabolic functions. Thyroid problems can be particularly important for the sleep-wake cycle, as it influences the metabolic rate of the body’s energy. While the estimates vary, approximately 10 million Americans have some form of thyroid hormone deficiency, and 40 percent will also have sleep apnea. This relationship has important treatment implications, and remains the focus of numerous studies looking to improve our understanding of these extremely common health conditions.

Hypothyroidism

The most common problem with the thyroid gland is hypothyroidism, or an underactive thyroid, which limits the production of hormones that the body needs for important metabolic functions. Getting improper sleep can have similar effects, and apnea events in particular can compound the symptoms and limit the thyroid’s ability to recover. Sleep apnea and thyroid problems are reciprocal in their influence, making it difficult to determine the root cause of their comorbidities, but it is always important to address both concerns in any treatment plan. In one study, nocturnal angina and heart arrhythmias developed in some patients undergoing treatment for hypothyroidism, despite the use of low doses of thyroxine to reverse the deficit. This was highly relevant because the treatment choice, known as thyroxine replacement, has shown positive results across the board, even decreasing overall Apnea-Hypopnea Index (AHI) results among patients with sleep apnea. In this case, the initiation of PAP therapy eventually reduced these complications, but still fell short of treating the thyroid issue itself. Thus, a combination of PAP therapy and mild thyroxine treatment was needed to address the concerns. This is why treatment plans must take every potential outcome into account and proceed with caution. From a medical perspective, every patient is unique and must be treated accordingly. Since patients with sleep apnea are at greater risk for developing hypothyroidism, the reverse is equally true. Due to multiple factors involved with respiration problems, such as a decreased ability to respond to chemical changes in the blood, the long-term effects of apnea events can damage the nerve systems that the thyroid and other endocrine functions depend upon. On the other hand, hypothyroidism can contribute to sleep apnea through the alteration of oral structures (macroglossia, for example) or by disruption of the muscles that control the upper airway. And both of these health concerns are highly linked to weight issues such as obesity, one of the biggest health problems in the world affecting one in ten human beings on the planet.

Shared Symptoms

Many symptoms of thyroid conditions are shared with those of sleep apnea, such as fatigue, weakness, weight gain, depression, decreased libido, and memory problems. But other symptoms are more clearly related to the thyroid, for example, changes in skin tone, hair, or nails are common signs of thyroid problems. The skin becomes rough or pale, hair falls out or becomes coarse, and nails become brittle or split from the base. Muscle cramps and intolerance to cold are also common, as the lack of proper metabolic hormones causes aches and sensitivity issues in different areas of the body. Studies have shown up to an 80 percent prevalence of sleep apnea diagnoses among patients with hypothyroidism, and this relationship is bi-directional. Either condition can result in the development of the other, and both can lead to cardiovascular complications. If left untreated, Hypothyroidism can result in decreased cardiac output and other heart problems, but in combination with sleep apnea, the risk of congestive heart failure is as high as 140 percent. In general, the link between sleep problems, metabolic dysfunctions, and heart conditions is growing stronger as studies uncover more about the interrelations of these comorbid conditions. What we know for sure is that sleep disorders such as central or obstructive sleep apnea can have deep-rooted metabolic and cardiovascular implications, whether it is the result or the cause of a problematic thyroid.

Hashimoto’s Disease

The most common causes of hypothyroidism are forms of inflammation that damage the thyroid cells. Hashimoto’s Thyroidititis, sometimes called autoimmune thyroiditis is a common form of thyroid inflammation caused by immune system dysfunction. Hashimoto’s has been to cause obstructive sleep apnea when the throat becomes swollen and breathing is inhibited. The thyroid becomes bigger, creating what is known as a goiter on the side of the neck, and the throat’s airway is narrowed as a result. About 4 in 10 patients with this form of thyroiditis will also develop sleep apnea. The good news is that treatments are improving for both sleep apnea and thyroid conditions. With proper health management, lifestyle adjustments, and treatment compliance, both sleep apnea and thyroid conditions can be reduced and normal energy levels can be restored.

Sleep Apnea and the Endocrine System

Sleep apnea is important to endocrinologists for a number of reasons. Most importantly, endocrine and metabolic disorders such as obesity and hypothyroidism are associated with a high rate of sleep apnea, and particularly high rate of obstructive sleep apnea. In some cases, treatment of the underlying endocrine disorder can improve and even cure the OSA. In other cases, both conditions can increase the risk of cardiovascular complications. In these cases, proper treatment is critical to the preservation of the patient, and immediate reduction of the risk becomes an urgent concern. Our understanding of the endocrine system’s role in sleep and sleep disorders is advancing with current research, but there is still a lot to learn. For those with sleep apnea, it is important to understand the risks of noncompliance with treatment. And for doctors and sleep specialists, the increased availability of hormonal tests and tools to diagnose sleep disorders has the additional benefit of detecting these coexisting endocrinal conditions early. This gives clinicians a chance for improved treatment recommendations at early stages of the disorders, allowing patients to receive the best possible care at pivotal moments in their life and health.