Low Blood Sodium in Older Adults

What is low blood sodium?

Low blood sodium, medically known as hyponatremia occurs when an abnormally low amount of the mineral sodium is found in the blood. This condition exists when sodium concentration in the blood falls below 135 mmo/L.

Low sodium in the blood commonly happens to older people, especially those who have been hospitalized of a long period of time or those who have undergone long term care. 

Causes of low blood sodium

Blood sodium level can be affected by a lot of factors in older people. One of them can be an excessive water intake and less frequent urination. Changes in the kidneys brought about by age such as decreased mass or blood flow to the organ may also be a factor that will bring about hyponatremia.

Aside from factors relating to how age may affect the body in metabolizing water, there are other factors that may contribute to low sodium in the blood. Taking certain medications may also help affect sodium levels in the body. Taking diuretics, pain medications as well as antidepressants may help bring down sodium levels.

Hypothyroidism or an under active thyroid gland may also affect how the body may be able to maintain normal sodium levels. The body’s failure to produce sufficient steroid hormones in the adrenal glands such as those afflicted with Addison’s disease may also be a factor in low sodium levels in the blood.

A disorder that may cause the overproduction of the antidiuretic hormone in the body may also affect low sodium levels in the blood. Other conditions that may help bring about low sodium levels in the blood include severe vomiting and diarrhea. Other diseases such as cirrhosis of the liver, kidney and heart failure may also contribute to lowering the level of sodium in the blood in due time.

Symptoms of low blood sodium

Old people having low blood sodium levels usually show no outward symptoms or signs that may tell that the condition occurs. The symptoms that do show may be more related to what caused the condition in the first place.

Some of the general symptoms that may be considered for people with hyponatremia include nausea, vomiting and headaches. As the hyponatremia becomes worse, patients may experience confusion as well as diminished reflexes. A worsening condition might further lead to convulsions and even stupor or coma.

How to treat low blood sodium?

Severe hyponatremia can lead to a shift of water content in the blood to go to the brain cells. Severe hyponatremia may lead to a fatal swelling of the brain if not addressed or treated immediately. Treating the condition may depend of the underlying cause of hyponatremia in patients.  

Electrolyte supplements such as hypertonic saline may be given in order to rapidly increase sodium levels in people with hyponatremia. Another type of drug used to treat low blood sodium is an Arginine vasopressin antagonist. This drug allows the body to undergo aquaresis or the excretion of free water.