By Dr Ananya Mandal, MD
Hyponatremia or a low blood sodium level is associated with several complications. In cases of chronic or long-term hyponatremia, the level of sodium in the blood drops gradually over days or weeks symptoms may therefore develop gradually and be of moderate severity.
In cases of acute hyponatremia on the other hand, the risk of developing potentially life-threatening complications is higher. The symptoms develop rapidly, over a very short period of time and may lead to a medical emergency. For example, acute hyponatremia can cause the brain to swell. This is a particularly dangerous condition called cerebral edema that can lead to coma and death within a matter of hours if left untreated.
Brain damage caused by hyponatremia appears to pose a greater risk among premenopausal women, possibly due to the influence of female sex hormones on the body’s ability to regulate sodium levels.
Some of the complications associated with hyponatremia are described below:
Chronic hyponatremia can lead to neurological complications that affect a person’s gait or walk as well as their ability to pay attention. Together, these effects lead to a reduced reaction time and an increased susceptibility to falls and injuries. Hyponatremia may also lead to the development of osteoporosis, which can increase the risk of bone fracture. One study showed that the odds of developing osteoporosis were almost three time greater among adults who had mild hyponatremia than among those who had normal blood sodium levels.
Acute hyponatremia can lead to much more severe complications such as cerebral edema, brain disease, herniation of the brain, cardiopulmonary arrest, seizure, coma and even death.
Reviewed by Sally Robertson, BSc
Last Updated: May 14, 2014