The Link of Clinical Risk Factors for Epilepsy Patients in Motor Vehicle Accidents

abstract & commentary

Source: Krauss GL, et al. Risk factors for seizure-related motor vehicle crashes in patients with epilepsy. Neurology 1999;52:1324-1329.

A variety of social and economic problems face persons with epilepsy, one being the capacity to drive an automobile to work or fulfill various other daily necessities. This report describes factors that influence the probability of some of these patients having automobile crashes. Krauss and associates identified from their large clinic 61 epileptic patients aged 21-70 who had crashed while driving. Eleven of the 61 crashed during their first seizure and were deleted from the study, leaving 50 "crashers" for analysis. The 50 crashers (mean age 38.5 years) were matched against 50 other epileptic "control" patients (mean age 39.8 years) from the same clinic. There were 41 males and 9 females populating both groups. None of the controls had ever crashed, but all had undergone two or more seizures and were taking medication. Neither type of seizure, years of driving, purposes of driving, nor type of roads differed between the two groups. Crashers, however, differed in several ways from controls. Seizure frequency was 2.9 per month in the crash group compared to 0.6 per month in the controls. The 50 crashers accumulated 74 seizure-related accidents, many causing severe injury and two being fatal. The controls had none. Major injury accompanied 17 crashers, nine others were injured, and two died. Among the crashers, 14 had more than one seizure-related accident. Additional items associated with a high accident rate included: short seizure-free intervals between attacks, a seizure incidence of 2.6 ± 1.2 per month compared to controls with 0.59 ± 0.17 episodes per month.

Favorable items associated with control patients consisted of: 1) long seizure-free intervals lasting 145 ± 29 weeks; 2) possessing reliable auras that always preceded major seizures; 3) having few prior crashes not related to seizures; and 4) having antiepileptic drugs changed, reduced, or withdrawn by their physician (the last point implies satisfactory improvement in the disease, or possible uncertainty of the diagnosis).

It should be mentioned that approximately one-third of all patients, well-controlled or not, were noncompliant in following medication, and about another third initially failed to report their seizures to the state’s motor vehicle department.


Krauss et al relate the bad-good outcomes in these 100 epileptic patients. Not surprisingly, they find that the more difficult to control the primary disease, the greater becomes the risk of automobile crashes or other injuries. They quote evidence that epilepsy increases standard accident rates by "only" 1.3-1.9 times. Your editor regrets even these low figures, thinking how sad it is for a person to suffer an embarrassing physiological disease, but also to be ashamed to drive or announce his or her disease to others. New pharmacology is only temporizing present therapy. Hopefully, new, brain-delivered medication or stimulation can completely repair some of these unfortunate epileptic patients. —fp

Which of the following is true about the crashers in the study of epilepsy patients in motor vehicle accidents?

a. Seizure frequency was 2.9 per month.

b. Some crashers had more than one seizure-related accident.

c. Crashers had 74 seizure-related accidents, with two being fatal.

d. All of the above