Fainting may be hereditary, but the triggers usually aren't

Study shows that the propensity for fainting may be genetic.
Thinkstock photo
Story by Jamie Lampros
Wed, May 8, 2013
Share this

Prone to fainting? It might be in your genes.

New research suggests that fainting might run in families, and a single gene may be the culprit. However, a predisposition to certain triggers might not be inherited.

The study, published April 16 in Neurology, included interviews with 44 families with a history of fainting. Of those, six families had a large number of people affected, suggesting that one gene was running through the family.

The first family included 30 affected people in three generations, with an average fainting onset at 8 to 9 years of age. The other families were made up of four to 14 affected family members.

Family members reported typical triggers, such as the sight of blood, injury, medical procedures, prolonged standing, pain and frightening thoughts, but the triggers varied widely within the families.

Genotyping of the largest family showed significant links to a specific region on chromosome 15, known as 15q26, according to the study.

“Our study strengthens the evidence that fainting may be commonly genetic,” said Dr. Samuel F. Berkovic, the study’s author. “Our hope is to uncover the mystery of this phenomenon so that we can recognize the risk or reduce the occurrence in people, as fainting may be a safety issue.”

Fainting refers to a sudden loss of consciousness, followed by a rapid and complete recovery, said Dr. Hans Jenkins, an Ogden family-practice physician.

Warning signs can include dizziness, nausea, pale skin, tunnel-like vision and profuse sweating, Jenkins said.

“I have several patients who have fainting episodes that also have family members with similar symptoms,” Jenkins said. “These patients have a type of fainting known as vasovagal or neurocardiogenic syncope. This type of fainting is caused by overstimulation of the vagal nervous system that causes the heart to slow down and thus decrease blood pressure to the brain and then fainting.”

A person who feels like he/she is going to faint, Jenkins said, should sit or lie down as quickly as possible and put their head between their knees. Also, a cool, wet cloth on the forehead will help.

Witnesses should remain calm and support the patient, Jenkins said. If that’s not possible, call 911 and start resuscitation measures.

“Patients who suffer from fainting can have tremendous amounts of stress from the disorder,” Jenkins said. “Fear of fainting in public can lead to social anxiety and even panic attacks. There are many causes of fainting and you should speak to your physician about it to see if it may be something serious.”

blog comments powered by Disqus