Vasovagal Syncope and Salt Supplementation

Abstract

Syncope is defined as a sudden and brief loss of consciousness and postural tonus due to cerebral hypoperfusion. Vasovagal syncope is the most common cause of syncope among all etiologies. The incidence may range from 21 to 35% and this condition usually affects young, healthy people. Its pathophysiology has not been elucidated yet, and it may due to vasodilation and reflex-mediated bradycardia. Some studies have been carried out as an attempt to find better therapeutic approaches for this dysautonomy which is often resistant to the treatments suggested. Pharmacological agents have been used, but the efficacy has not been fully proven and adverse effects are common. Currently, there are few randomized studies and most of them involve small samples. Therapeutic measures have been suggested to prevent relapses, including general non-pharmacological approaches such as recognizing the symptoms and the triggering factors, programs of physical and postural training, increase in the water and salt intake. Some findings suggest there is an influence of salt supplementation in the clinical parameters of vasovagal syncope. The mechanism that prevents syncope using salt administration has not been completely understood, although its efficacy is attributed to the expansion of the extracellular volume. Salt supplementation can increase body weight, plasma volume, orthostatic tolerance and blood pressure in the upright posture. However, a specific subgroup of people who presents with symptoms that are not appropriately controlled need intervention pharmacological and non pharmacology. In general, good therapeutic results are achieved with changes in diet and behavior.