Abstract & Commentary
Synopsis: The rate of seizure-related crashes did not significantly increase in the state of Arizona after the seizure-free interval was reduced from 12 to 3 months.
Source: Drazkowski JF, et al. Mayo Clin Proc. 2003;78:819-825.
When is it safe to sit behind the wheel if you’ve just had a seizure? Specific seizure-free intervals vary from state to state. In this time-trend study, an analysis was undertaken to determine if lowering the interval from 12 months to 3, as was done in Arizona, increased motor vehicle accident (MVA) frequency. Seizure-related MVAs were defined as such if the patient self-reported a seizure at the time of the accident, was witnessed to have a seizure or was confused at the scene in the absence of head trauma, or had low anti-epileptic drug levels as reported by hospital personnel. Non seizure-related MVAs included cardiac-related crashes due to arrhythmia or myocardial infarction and diabetes-related MVAs as documented by hypoglycemia, altered consciousness, or response to intravenous glucose at the scene. Psychiatric conditions, medication effects, stroke, visual impairment, dementia, and migraine comprised other medically related MVAs. Crash incidence rates were obtained by dividing the number of MVAs by the number of miles driven, as estimated from the Arizona State Motor Vehicle Department annual report.
Approximately 614,000 MVAs were reported during the 6-year study period, 859 of which were medically related. Comparing 1991-1993, when a 12-month seizure-free interval was required, to 1994-1996, when the interval was lowered to 3 months, the number of seizure-related MVAs increased slightly from 125 to 136. Based on incidence rate, however, seizure-related MVAs dropped by 2%, not a significant difference, despite an 8% increase in MVAs overall. Fatality incidence dropped by 64%, but injuries associated with seizure-related MVAs increased 31%. No significant change was evident in mean age of driver (37 vs 38 years of age), percentage of urban accidents, or percentage of single- vs multiple-car MVAs. Arizona’s excellent weather patterns and road conditions precluded inclement weather or road surface from playing a role in any crash. MVAs related to other medical conditions similarly showed no significant change. Common sense must always prevail, but limiting driving restriction to 3 months following a seizure appears safe and reasonable.
Comment by Michael Rubin, MD
This report supports the consensus developed at a symposium held in Quebec City in November 1998, regarding epilepsy and driving.1 Attendees included an invited international group of neurologists from Canada, the United States, and Europe; Canadian licensing representatives; and delegates from the Canadian Council of Motor Transport, the Canadian Medical Protective Association, and the Canadian Medical Association. Among the medical experts, abolition of mandatory reporting of epilepsy to the Motor Vehicle Department (as is the law in Canada) was felt to be desirable. Most patients, it was felt, could return to driving private automobiles within 6-12 months of seizure freedom. First and foremost, observance of local laws remains paramount until changes are appropriately legislated.
Dr. Rubin is Professor of Clinical Neurology, New York Presbyterian Hospital-Cornell Campus.
1. Remillard GM, et al. Can J Neurol Sci. 2002;29: 315-325.