Blog #90: Which Patients with Epilepsy Can Safely Drive?

 

            The perennial question from our patients is, “Can I drive, Doctor?” Only California, Delaware, New Jersey, Nevada, Oregon and Pennsylvania throw this decision to the state’s Department of Motor Vehicles (DMV). These states’ laws make it mandatory for physicians to report persons who are diagnosed with epilepsy to the state DMV; however, it is the DMV that decides if the patient may drive, not the physician. Failure to report an epilepsy diagnosis opens the physician to liability if car accidents occur. The other 44 states request patients to report themselves to the DMV. Facing loss of jobs, income and losing their driving privilege makes it very tempting not to report their epilepsy diagnosis. But, this compromises their own safety, the safety of their passengers and of the public. I have had patients who had their driving licenses revoked for a period of observation of six to twenty-four months. If they were seizure-free the DMV returned their driving privilege. In my follow-up, I would query, “Have you had any seizures or spells?” Some had responded, “Would you have to report anything to the DMV?” When I affirmed that I would, they then told me, “No, I’m doing fine, Doctor.”

            The patient’s doctor, usually a neurologist, is asked on the DMV’s forms whether the patient is safe to drive: “yes, no or unsure.” Physicians base their judgement on the patient’s and observer’s histories if loss of awareness has occurred. The DMV’s medical consultant committee, however, makes the ultimate driving decision.  

            The EEG is normal in up to 50% of epilepsy patients on any one test. Abnormalities may not appear except during seizure activity in the brain. EEG abnormalities of other types are not always diagnostic. Brain scans and blood and cerebrospinal fluid testing are commonly normal, too. So, a normal EEG does not rule out epilepsy. The clinical history is how the diagnosis of epilepsy is made.

            Petit Mal, or Absence, seizure patients usually have no warning-prodrome or post-ictal (after the seizure stops) confusion state or any obvious physical changes during their seizure. Also, these patients are oblivious of their loss of awareness which usually last just 10-15 seconds. Observers who are unfamiliar with epilepsy―often their juvenile friends—commonly miss the brief seizure; they consider the patient “weird” and “different.” Complex partial seizures can be hard to identify because the person does not convulse but just seems to be confused and to have lost contact with their environment.

            The lack of data about driving performance during seizures, and during the post-ictal period, makes it difficult to determine driving safety. A study of patients who performed a driving simulation test during inpatient video-EEG monitoring was recently reviewed.¹ Hal Blumenfeld, MD, PhD and colleagues studied 20 patients during simulated driving in the Yale New Haven Hospital Epilepsy Monitoring Unit. Patients “drove” an average of three hours. Some seizures showed obvious impairment and others showed none. Several of the patients’ seizures resulted in “crashes.” Seizures lasted an average of 75 seconds in those patients who crashed, compared with an average of 30 seconds in patients who did not crash. Blumenthal concluded that “…more data is required to learn if there are people with epilepsy who are driving who shouldn’t be driving, as well as those who are not driving who can safely drive.”

            Another similar study also questions the long-held belief of a protective role of reliable auras against motor vehicle accidents in people with epilepsy.² 

1.      “Which Patients with Epilepsy Can Safely Drive” Neurology Reviews: January 2017, page 8.

2.       Punia V, Farooque P, Chen W, et. al. Epileptic auras and their role in driving safety in people with epilepsy. Epilepsia. 2015 Nov; 56(11): e182–e185. Free at Epilepsia.

 

Lance Fogan, M.D. is Clinical Professor of Neurology at the David Geffen School of Medicine at UCLA. “DINGS” is his first novel. It is a mother’s dramatic story that teaches epilepsy, now available in eBook, audiobook and soft cover editions.