Dec 15, 1999 (Baltimore) -- A new study finds that people with syncope, or fainting spells, can drive safely with minimal or no risk of passing out while driving.
"Estimates of syncope indicate that the condition is extremely common, accounting for about 1-6% of all hospital admissions and 3% of all emergency room visits," says Atul Bhatia, MD, a fellow in cardioelectrophysiology at the University of Wisconsin in Madison and lead author of a paper on syncope and driving.
"About 30% or so of those people have what we call neurocardiogenic or vasovagal syncope. We studied these people to see if the condition occurred while they were driving." The paper appears in the November issue of the journal PACE.
Neurocardiogenic syncope occurs when blood flow to the brain is decreased due to reduced blood flow from the heart and falling blood pressure. The exact cause is often unknown and syncope can occur with little forewarning. Therefore, physicians have traditionally discouraged patients with this type of syncope from driving.
The condition can be diagnosed by use of a tilt-table test. During this test, patients lie flat on a table that is put into various positions, and patients are monitored to see whether they experience feelings of faintness or have abnormal changes in blood pressure and heart rate with the changing position of the table.
Bhatia and colleagues studied 155 people who had reported syncope in the past and who experienced the condition while they were being tested with a tilt-table test. Study participants were also asked to fill out a questionnaire about their driving habits and any previous injuries or accidents. They were then put on medications to reduce the episodes of syncope and periodically asked to fill out the driving questionnaire again.
The researchers found out that in patients who took medications to reduce their episodes of syncope no one had syncope while driving. People who stopped taking medications did experience episodes of syncope but not while driving. "We think that there may be something about the posture while driving that may protect even those who do have syncope from experiencing an episode then," says Bhatia. Syncope is less likely to occur while someone is sitting, as blood flow is able to reach the brain more easily.
Most people in the study began driving much more and driving on the highway more often than before their condition was identified and treated. Says Bhatia, "One of the first questions patients have is, 'Can I drive safely?'" Our study allows us to reassure them that they can."
William Herzog, MD, associate professor of cardiology at the University of Maryland School of Medicine, reviewed the study for WebMD. He says, "This is a very important contribution to the literature on this topic. It helps to guide us when patients ask if it is safe for them to drive."
However, consensus among the medical community is needed in order to provide specific guidelines regarding driving in patients with syncope, according to Bhatia and colleagues.