Published May 14 2018
There are numerous symptoms associated with hyperthyroid and hypothyroid conditions. Some of the more common symptoms people with hypothyroidism experience include fatigue, weight gain, brain fog, cold hands and feet, and constipation. As for those with hyperthyroid conditions, common symptoms include an increased resting pulse rate, heart palpitations, tremors, weight loss, an increased appetite, and loose stools. You don’t hear much about how thyroid hormone imbalances affect the respiratory system, thus playing a role in conditions such as air hunger and sleep apnea, but in this article I’m going to discuss this relationship.
Before I discuss some of the imbalances associated with the respiratory system, let’s take a brief look at the physiology of respiration. First of all, the respiratory tract is the path of air from the nose to the lungs. It helps to pull oxygen into our body, and is responsible for the excretion of carbon dioxide. But I want to focus on something called cellular respiration. This involves the mitochondria, which is an organelle found in almost all cells, and the primary function of the mitochondria is to produce something called adenosine triphosphate (ATP).
It is actually in the mitochondria where oxygen is consumed and carbon dioxide is produced. What’s important to understand is that these mitochondria are nutrient-dependent. In other words, the mitochondria uses these nutrients to help form ATP. As a result, if you have nutrient deficiencies, this can have a negative effect on cellular respiration.
What is Dyspnea?
Dyspnea is also known as “shortness of breath”. According to the American Thoracic Society, dyspnea is defined as “a subjective experience of breathing discomfort that consists of qualitatively distinct sensations that vary in intensity.” (1). Some also describe this as “air hunger”, or the feeling of not getting enough oxygen. As you can imagine, there are different causes of dyspnea/air hunger, and just because you have a thyroid or autoimmune thyroid condition doesn’t mean that this is the main cause. This is why it’s important to get evaluated by a competent healthcare practitioner.
There is also a difference between acute and chronic dyspnea. Chronic dyspnea is when the person has had shortness of breath for longer than four weeks. While a thyroid hormone imbalance can be a factor in some cases, other potential causes of chronic dyspnea include bronchial asthma, COPD, congestive heart failure, interstitial lung disease, pneumonia, and mental disorders (2).
As for acute dyspnea, if this is accompanied by confusion, marked cyanosis (blue discoloration of the skin), shortness of breath while speaking, and insufficient respiratory effort or respiratory exhaustion, then this needs to be evaluated at once, as in some cases it can be due to a life-threatening condition, such as a thyroid storm. It’s also common for emotional factors to worsen the dyspnea. For example, the dyspnea itself can make the person more anxious, which can exacerbate the symptoms.
In addition to measuring the vital signs, along with the oxygen saturation of the blood, other diagnostic methods may be used. For example, a chest x-ray might be recommended to see if there is any pulmonary congestion, pneumonia, or pneumothorax. An ECG might also be recommended. Spiroergometry might also be used to distinguish cardiac from pulmonary causes of dyspnea.
Dyspnea and Hyperthyroidism
Although some people with hypothyroidism and Hashimoto’s experience dyspnea, shortness of breath is more common in those with hyperthyroidism and Graves’ disease. One study showed that increased breathing effort may lead to dyspnea during hyperthyroidism, but the good news is that there was a significant reduction in dyspnea once the thyroid hormone levels were normalized (3). Another study confirmed that dyspnea is more common in hyperthyroid patients than controls (4).
Dyspnea and Hypothyroidism
As I just mentioned, dyspnea is more common in hyperthyroid conditions, although it can also occur in some people with hypothyroidism. The author of a journal article mentioned that when dyspnea occurs in hypothyroidism it is most likely related to a limited ventilator and cardiac reserve, in addition to decreased inspiratory and expiratory muscle strength (5). However, they also added that respiratory manifestations usually aren’t present initially in those with hypothyroidism. Another study mentioned how some patients with hypothyroidism have expiratory dyspnea caused by partial upper airway obstruction through edema and mucopolysaccharide infiltration (6).
What is Sleep Apnea?
Sleep apnea is when your breathing repeatedly stops and starts during sleep. Obstructive sleep apnea syndrome (OSAS) is a common disorder characterized by repetitive episodes of nocturnal breathing cessation due to upper airway obstruction (7). There is also something called central sleep apnea, which occurs because your brain doesn’t send proper signals to the muscles that control your breathing.
Although I’ll talk about the relationship between sleep apnea and thyroid health shortly, there can be other causes. Some of the causes of central sleep apnea include having a stroke, severe obesity, conditions of the cervical spine, and certain medications (i.e. narcotic painkillers) (8). Some of the causes and risk factors of obstructive sleep apnea include excess weight and obesity, a narrowed airway caused by enlarged tonsils or adenoids, high blood pressure, chronic nasal congestion, smoking, asthma, and diabetes (9).
Hypothyroidism and Sleep Apnea
One case study revealed that a 45-year old male patient developed central sleep apnea syndrome due to hypothyroidism, and upon taking thyroid hormone replacement reversed the condition (10). Another study looked at the relationship between obstructive sleep apnea syndrome and hypothyroidism (11). The study found that only two out of 65 patients with obstructive sleep apnea syndrome had hypothyroidism. The study also looked at 20 hypothyroid patients, and found that two of them showed moderate to severe OSAS and three had mild OSAS. The study concluded that thyroid hormone replacement is effective for OSAS, and that age and body weight are related to the development of OSAS.
A systematic review looked to identify the prevalence and underlying mechanisms of respiratory problems in those patients with hypothyroidism (12). The study showed that OSAS was found among 30% of newly diagnosed patients with overt hypothyroidism, and demonstrated reversibility following treatment.
Hyperthyroidism and Sleep Apnea
I wasn’t able to find a direct correlation between hyperthyroidism and sleep apnea. One study I came across looked at the prevalence of thyroid disease in patients with OSAS (13). In this study there were no cases of overt or subclinical hyperthyroidism. This of course doesn’t mean that people with hyperthyroidism can’t have sleep apnea, but the hyperthyroid state doesn’t seem to be an underlying case.
Other Respiratory Conditions Associated With Thyroid Health
Pulmonary hypertension. Pulmonary hypertension is a type of high blood pressure which involves narrowing of the arteries that carry blood from the heart to the lungs. Symptoms can include shortness of breath, fatigue, chest pain, and an increased resting heart rate. With regards to thyroid health, pulmonary hypertension is more commonly associated with hyperthyroidism (14) (15), and treating the hyperthyroidism can help to improve the pulmonary hypertension.
Chronic obstructive pulmonary disease (COPD). A few studies demonstrate a link between COPD and thyroid health. One study assessed the impact of thyroid dysfunction in patients with COPD (16). The study evaluated pulmonary function tests, arterial blood gases, maximal inspiratory pressure, maximal expiratory pressure, and thyroid function in patients with COPD, and the results showed that patients with overt hypothyroidism have a greater impairment of maximal inspiratory pressure and maximal expiratory pressure. Another study evaluated the effects of thyroid function on quality of life and exacerbation frequency in COPD patients (17). The results of the study suggested that thyroid function can exacerbate the frequency of COPD.
Asthma. Although there isn’t much in the research regarding asthma and Graves’ disease, one thing these two conditions have in common is that they seem to be characterized by a predominance of Th2 cytokines (18) (19) (20). This might suggest that improving the health of the immune system in someone with Graves’ disease would potentially improve their asthma as well. However, it’s worth mentioning that some studies consider Graves’ disease to include a combination of Th1 and Th2 cytokines (21). It’s also important to know that in some cases hyperthyroidism can worsen asthma (22), and so if someone who has both hyperthyroidism and asthma experiences shortness of breath, it can be due to the hyperthyroidism, exacerbation of asthma, or a combination of these two factors.
Respiratory infection. Not surprisingly, respiratory infections can lead to symptoms such as shortness of breath. This is especially true in severe respiratory infections, such as pneumonia. Some reading this are familiar with thyroid storm, which can be a life-threatening condition, and systemic pulmonary infections can be one potential cause (23) (24).
Goiter-induced upper airway obstruction. Very large goiters can cause upper airway obstruction, and lead to symptoms such as shortness of breath, as well as difficulty in swallowing. Fortunately this isn’t too common, but when upper airway obstruction does occur in the presence of a very large goiter, it’s usually due to compression of the trachea. However, sometimes the airway obstruction isn’t due to the goiter itself, but instead is caused by edema of the upper airway (25).
What Are Some Natural Treatment Options?
The treatment options for the different respiratory conditions described in this article depend on the cause of the problem. For example, if shortness of breath is a consequence of hyperthyroidism or hypothyroidism, then of course the goal should be to address the thyroid hormone imbalance. If the condition is autoimmune in nature (Graves’ disease or Hashimoto’s thyroiditis) then reversing the autoimmune component is necessary in order to permanently balance the thyroid hormone levels, but in the meantime the person might need to take antithyroid medication (for hyperthyroidism) or thyroid hormone replacement (for hypothyroidism) to balance their thyroid hormones.
Similarly, if someone has sleep apnea due to a thyroid hormone imbalance, then the thyroid hormone levels need to be balanced to help with this. Correcting the thyroid hormone imbalance can at times also help with other conditions I discussed in this article, including pulmonary hypertension and COPD.
I also spoke specifically about large goiters causing airway obstruction, thus causing shortness of breath. While an increase or decrease in thyroid hormone can cause a goiter, there can be other factors in the formation of a goiter, including an iodine deficiency. A few years ago I wrote an article about shrinking goiters through supplements and herbs that you might want to check out.
Of course there can be other areas unrelated to the thyroid gland that need to be addressed. Earlier I mentioned the role of the mitochondria in cellular respiration, and I also discussed how mitochondria are nutrient dependent. And so correcting certain nutrient deficiencies is required to have properly functioning mitochondria, which in turn is important for healthy respiration. Some of the nutrients which play an important role in the health of the mitochondria include coenzyme Q10, magnesium, carnitine, and the B vitamins. In fact, a few studies have shown that taking at least 200mg/day of CoQ10 can help with some cases of dyspnea (26) (27). There is also evidence that taking 500 to 1,500mg of L-carnitine per day can help to improve dyspnea (28) (29).
If someone has a respiratory infection that is causing shortness of breath then it goes without saying that this needs to be addressed. And we also can’t overlook the psychosomatic component involved when someone experiences air hunger. This isn’t to suggest that most cases of dyspnea are psychological in nature, but as I briefly mentioned earlier, when someone experiences air hunger they frequently will experience anxiety, which will only exacerbate the symptoms.
In summary, some of the respiratory symptoms and conditions in those with thyroid and autoimmune thyroid conditions include shortness of breath, sleep apnea, pulmonary hypertension, COPD, asthma, and goiter-induced upper airway obstruction. Respiratory infections and mitochondrial dysfunction are other factors to consider. If a thyroid hormone imbalance is responsible for symptoms such as air hunger or sleep apnea, then of course it is necessary to correct this imbalance. On the other hand, if someone is having respiratory symptoms due to other factors mentioned in this article, then this obviously needs to be addressed.