Hypothyroidism and hyponatremia – what are they and what is their relationship?
To function properly the human body requires specific levels of electrolytes to be present in our blood. Sodium is one these electrolytes and if the concentration of blood sodium drops to abnormal levels it causes a condition called hyponatremia. Therefore hyponatremia essentially means that your water and sodium levels are unbalanced and it can be caused by excessive fluid intake, insufficient sodium intake or abnormal sodium loss.
Sodium is crucial because it controls water levels in and around our cells. When there is too much water present and not enough sodium to regulate it cells start swelling, causing a range of symptoms and health issues:
- Low energy
- Muscle cramps or spasms
- Muscle weakness
- Restlessness and irritability
If the condition becomes severe enough it can bring on seizures or coma and may also be fatal.
Causes Of Hyponatremia
Hyponatremia can be caused by a number of things:
- excessive consumption of fluids, which dilutes blood sodium levels
- heart failure
- kidney failure
- cirrhosis of the liver
- pain medications and antidepressants
- Addison’s disease
- SIADH – syndrome of inappropriate anti-diuretic hormone
It should also be noted that it is possible to develop temporary low blood sodium levels through a number of causes such as chronic vomiting or diarrhea, dehydration, ecstasy use etc. However, taking the appropriate actions to restore normal sodium levels, either through drinking more fluids or taking electrolytes, will usually reverse this situation relatively quickly.
Are Hypothyroidism And Hyponatremia Linked?
Hypothyroidism is a condition in which the thyroid gland doesn’t produce enough thyroid hormone. Is it linked with hyponatremia? Historically it has been, not the least because some patients with hypothyroidism have an impaired glomerular filtration rate (GFR). This is usually corrected with thyroid replacement therapy.
More recent research though is emerging to challenge the idea that hypothyroidism and hyponatremia are associated. A study of the available literature in fact suggests that there is not enough consistent evidence to prove the low levels of GFR impairment in patients with mild to moderate hypothyroidism are sufficient to cause hyponatremia.
Furthermore, studies that have looked at the relationship between hypothyroidism and hyponatremia have often focused on patients with myxedema coma, a condition that has repeatedly been linked with hyponatremia. Certainly myxedeme coma is able to cause a big enough drop in GFR to impair kidney function to the point where hyponatremia can develop. However, multi-organ failure generally is very common in myxedema patients so this may also contribute to the development of hyponatremia in these patients.
Interesting Questions about Thyroid:
If you or a blood relative has Hashimoto’s thyroiditis or Graves’ disease, there is a chance that your children will inherit the problem. These diseases are also linked to other autoimmune conditions, such as premature gray hair, diabetes mellitus, arthritis, and patchy loss of skin pigment (vitiligo). You should tell your child’s doctor, so that the appropriate examinations can be performed.
Also, one out of every 4,000 infants is born without a working thyroid gland. If the problem is not corrected, the child will become mentally and physically retarded. Therefore, all newborns in the United States are tested for the disease. Once the problem is discovered and corrected, the child can grow up normally.
When are beta-blocking drugs used?
Beta-blocking drugs, also called beta blockers, treat the symptoms of hyperthyroidism. They do not significantly affect the gland or the levels of thyroid hormones in the blood. Instead, they “block” the effects of thyroid hormones.
Beta blockers are most useful for patients whose hyperthyroidism makes them uncomfortable. High hormone levels can cause a faster heart rate and trembling. Beta-blocking drugs help control these symptoms.
Beta-blocking drugs should not be used by patients with asthma.
Between one and two million Americans received radiation treatments in childhood or adolescence between 1920 and 1960. The most common reasons for these treatments were:
- enlarged thymus gland
- enlarged tonsils and adenoids
- various chest conditions
The risk factor for developing thyroid cancer if you had childhood radiation treatments is between 2% and 7% as compared to .004% in the general population.
There have been cases of side effects from radiation treatments (not radioactive iodine treatments) reported as long as 45 years after treatment.
Most physicians agree that the thyroid gland of these patients should be checked annually.
Some physicians rely solely on physical (manual) examination of patients treated as children with radiation. Others prefer to perform scans or ultrasounds for nodules too small to detect manually that might be cancerous.
A person treated as a child with radiation can request that their medical records be sent to them by writing the hospital or clinic where they had the treatments. Ask for a record of how much each dose of radiation was as well as how often and over what period of time treatments were given.
Have more questions? Need more answers? Check our Full Thyroid FAQ
Who Is Most At Risk Of Developing Hyponatremia
The elderly, simply because as we age we’re more likely to
- develop age related health conditions that affect our ability to remove excess water from our system and/or affect sodium levels
- require medications that likewise affect our ability to remove excess water
People who require some types of drugs, notably
- pain relief medications
People with diseases that reduce the effective of our renal system like
- kidney disease
- heart disease
- liver disease
- Addison’s disease
Athletes and anyone who is involved in rigorous physical activities such as
- marathon runners and other long distance sports
- hard manual work in hot temperatures
People who take Ecstasy, a recreational drug that is on record has having caused multiple fatal incidents of hyponatremia.
Diagnosis And Treatment Options For Hyponatremia
As always with health conditions like hypothyroidism and hyponatremia, it’s best to seek medical advice and follow the instructions given to you by those with the training and qualifications to provide such advice. If you suspect you may have this condition based on some of the above symptoms and you’re in one of the high risk categories, your doctor will order urine and blood tests to determine your blood levels of sodium. High levels of sodium in urine and low levels in blood is a sign that you’re losing more sodium than you’re retaining.
Treatment for hyponatremia in most cases usually focuses on rectifying or preventing the underlying condition that is causing the hyponatremia. For mild hyponatremia, ensuring that you are well hydrated but not excessively so, and getting enough dietary sodium is usually sufficient to reverse this condition. If you’re sweating, drink only enough to replace those fluids – thirst is a good gauge of how much you need to drink. When you’re no longer thirsty, stop drinking and consider using electrolyte drinks instead of just plain water.
If you know you have a health condition that predisposes you to developing hyponatremia be vigilant. Know what the symptoms of low sodium levels are and be prepared to take preventative action as per medical instructions when you experience them. If you do also have hypothyroidism you may, as we’ve noted, also have a degree of impaired glomerular filtration rate. However, taking your thyroid medications regularly should reverse this situation.
Drink enough water to remain hydrated. Your urine should be pale yellow and clear. Your thirst levels will also tell you when you need to take in more fluids.
Severe hyponatremia may require hospitalization and IV fluids.