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You don’t even have to think about it. Breathing happens and is essential to life. When we breathe in oxygen, we expel or breathe out carbon dioxide.
Too much carbon dioxide in your bloodstream prevents oxygen from entering, causing hypoxia, a state of having low levels of oxygen in your tissues, preventing your organs from functioning properly. Your lungs are where this very important oxygen-carbon dioxide exchange occurs.
While breathing is completely second nature to us, many hormones, muscles, and body systems are involved. We will focus on one of these hormones, thyroid hormone, and see how it affects your breathing.
A small, butterfly-shaped gland called your thyroid gland sits at the bottom of your neck with its main role to release thyroid hormones. Once in your bloodstream, thyroid hormones travel to different organs where they can help with:
- Controlling your metabolism
- Maintaining mental, muscle, skin, and hair health
- Growth and development
- Producing heat
Every cell and organ in your body needs thyroid hormones to function. But your thyroid gland can release too much or too little. Too much thyroid hormone, or an overactive thyroid gland, called hyperthyroidism, causes your body functions to go faster. In contrast, hypothyroidism, too little thyroid hormone, slows down your body functions.
Some hypothyroidism symptoms include:
- Weight gain
- Feeling tired or weak
- Brittle hair and dry skin
- Cold intolerance
Short answer - yes, both hyperthyroidism and hypothyroidism can.
Hypothyroidism, an underactive thyroid gland, and the main symtpoms of autoimmune disorders such as Hashimoto's thyroiditis, can cause mild breathing problems to life-threatening respiratory failure. Here is how:
All your muscles need thyroid hormone to contract, a process where your muscles shorten, lengthen, or tighten to complete an activity. In the case of your lungs, contracting is the activity of us breathing.
Pulmonary function tests measure how well you are breathing, and your lungs are functioning. According to research, people with hypothyroidism or lower thyroid function tend to score lower on pulmonary function tests compared to those with normal or high levels of thyroid hormones. Because of this, those with hypothyroidism can experience exercise intolerance.
Inhaling and exhaling involve many muscles. Your diaphragm, located below your lungs, is one of the major muscles involved. Low levels of thyroid hormone reduce your muscle tone, causing muscle weakness and making it harder to breathe. Mild weakness of your diaphragm can cause exercise intolerance, while severe weakness can lead to shortness of breath at rest.
Your lungs contain tiny air sacs called alveoli that allow oxygen to enter your blood. Specific lipids and proteins make up a substance called pulmonary surfactant which covers your alveoli to help:
- Protect your lungs from infections and injuries
- Keep alveoli open
- Remove extra fluid from the lungs
Since your lungs need thyroid hormones for growth, development and for making pulmonary surfactant, any changes in the makeup or amount of pulmonary surfactant can affect the amount of oxygen entering your blood.
Both hypothyroidism and hyperthyroidism can cause a goiter, an enlargement of your thyroid gland. As your thyroid gland gets bigger, the amount of air moving through your trachea, also known as your windpipe, to your lungs decreases. Because of this, you can have the following:
- Trouble breathing
- A high-pitched breathing sound (stridor)
Sleep apnea is condition when your breathing stops and restarts while you are sleeping and can affect how much oxygen your are getting into your lungs throughout the night. Snoring or gasping for air while sleeping are common conditions and signs of sleep apnea.
About 25% of people with hypothyroidism, or autoimmune conditions like Hashimoto's also have obstructive sleep apnea, a type of sleep apnea caused by blockage of the upper airway. Risk factors for obstructive sleep apnea include being overweight or changes in hormone levels. Low levels of thyroid hormone may contribute to sleep apnea by causing:
- Weight gain
- Obstruction due to deposits of proteins and sugars in your upper airway
- Decrease in oxygen-carbon dioxide exchange
A pleural effusion is when fluid builds up in the layers of tissue between your lungs and chest wall (pleural space).
People with hypothyroidism can develop pleural effusions. Usually, the volume of extra fluid in the pleural space is small - less than ⅓ of your pleural cavity. But, larger amounts of fluid can build up, especially in the setting of pneumonia, cardiac failure, or other medical conditions associated with hypothyroidism.
Small amounts of fluid that build up in your pleural space usually won’t cause symptoms. But large amounts can cause:
- Fast breathing
- Shortness of breath
- Chest pain
While the exact reason this occurs is unknown, hypothyroidism makes it easier for fluid to move from your small blood vessels (capillaries) into the pleural space.
While uncommon, those with untreated or undiagnosed hypothyroidism can develop a life-threatening condition called myxedema coma. Very low levels of thyroid hormone as seen in myxedema coma can lead to respiratory failure, making it hard to breathe on your own. Because of this, carbon dioxide levels in your body increase while oxygen levels will decrease.
Myxedema coma is a medical emergency that requires treatment in a hospital. Symptoms include:
- Decreased breathing
- Low blood pressure or blood sugar
- Changes in mood
- Below normal body temperature
Hypothyroidism is manageable by taking thyroid hormone replacement, usually thyroxine (T4). If hypothyroidism is the cause of your breathing problems, overtime a thyroxine treatment plan can help:
- Improve lung weakness
- Decrease the amount of fluid in your pleural space
- Reduce the size of your goiter (won’t completely go away)
People with obstructive sleep apnea may see symptom improvement with thyroid hormone replacement medications. But sleep apnea usually won’t go away completely. This is because other factors like being overweight also contribute to sleep apnea.
Knowing your thyroid levels is the first step to making sure your thyroid is functioning correctly and preventing breathing complications. A finger prick blood sample blood test is all it takes with our at-home testing kit.
If you lab results come back elevated, Paloma Health has a team thyroid doctors available to help you understand your results and create the optimal treatment plan for you. Book an appointment and receive quality care from the comfort of your own home today.