Syncope while driving: clinical characteristics, causes, and prognosis.

Abstract

The risk of syncope occurring while driving has obvious implications for personal and public safety. We aimed to define the clinical characteristics, causes, and prognosis of syncope while driving. In this case-control study of consecutive patients evaluated for syncope from 1996 through 1998 at an academic medical center, we documented causes, clinical characteristics, and recurrence of syncope while driving. Of 3877 patients identified, 381 (9.8%) had syncope while driving (driving group). Compared with the 3496 patients (90.2%) who did not have syncope while driving, the driving group was younger (P=0.01) and had higher percentages of male patients (P<0.001) and patients with a history of any cardiovascular disease (P=0.01) and stroke (P=0.02). Syncope while driving was commonly caused by neurally mediated syncope (37.3%) and cardiac arrhythmias (11.8%). Long-term survival in the driving group was comparable to that of an age- and sex-matched cohort from the Minnesota population (P=0.15). Among the driving group, syncope recurred in 72 patients, 35 of whom (48.6%) had recurrence >6 months after the initial evaluation. Recurrences during driving happened in 10 patients in the driving group, 7 of which (70%) were >12 months after the initial evaluation. In our study, neurally mediated syncope was the most common type of syncope while driving. The causes of syncope, the late recurrences of syncope (during > or =6 months of follow-up), and the overall low incidence of recurrent syncope while driving provide useful information to supplement current recommendations on driving for these patients.