Do drivers with epilepsy have higher rates of motor vehicle accidents than those without epilepsy?

OBJECTIVE We sought to understand the magnitude of the risk that drivers with epilepsy (DWE) contribute to motor vehicle accidents (MVAs) compared to other drivers. METHODS We performed an evidence-based, systematic review using the American Academy of Neurology (AAN) guideline methodology. RESULTS Contributory evidence consisted of six Class II studies and one Class III study. Two articles reported a trend toward a decreased rate of overall MVA rates for DWE when compared with the general population with a relative risk (RR) of 0.86 (95% CI: 0.65-1.14) (Class III) and a RR of 1.00 (95% CI: 0.95-1.06) (Class II); both studies used patient report to ascertain MVA rates. Three Class II studies reported either a trend toward or an increased risk of MVA rates for DWE when compared with the general population with a RR of 1.62 (95% confidence interval (CI): 0.95-2.76), as ascertained by insurance, emergency department, and physician reporting databases, a RR of 1.73 (95% CI 1.58-1.90), as ascertained by police reports, and a RR of 7.01 (95% CI 2.18-26.13), as ascertained by casualty department visits. One Class II study showed that, compared to fatal crashes with DWE, fatal crashes were 26 times more likely to occur because of other medical conditions and 156 times more likely to occur because of alcohol abuse. Motor vehicle accident crashes due to seizures in DWE occurred in one out of every 2800 MVAs, as reported in another Class II study. CONCLUSIONS The evidence for the difference in MVA rates in DWE compared to the general population is inconsistent, and no conclusion can be made. Important methodological differences across the studies contribute to the imprecision. Future research should be performed using objective measures rather than self-reporting of MVAs by DWE and "miles driven" as the denominator to calculate MVA rates.