VIGILANCE AND AUTOMOBILE ACCIDENTS IN PATIENTS WITH SLEEP-APNEA OR NARCOLEPSY

Patients with obstructive sleep apnea or narcolepsy report difficulty remaining alert and attentive, To detect impaired vigilance, me design ed Steer Clear, a computer program simulating a long and monotonous hi ghway drive that presents 780 obstacles in 30 min. Sixty-two patients with sleep apnea hit a higher percentage of obstacles (4.3+/-0.6% [SEM ]) than 12 age- and sex-matched subjects without sleep apnea (1.4+/-0. 3%; p<0.05) and 10 age- and sex-matched volunteers (1.4+/-0.3%; p<0.05 ). Ten patients with untreated narcolepsy hit a higher percentage of o bstacles while performing on Steer Clear (7.7+/-3.2%) than 10 age- and sex-matched subjects without narcolepsy (1.2+/-0.3%; p<0.05), Poor pe rformance on Steer Clear was associated with a higher auto accident ra te in the patients with sleep apnea or narcolepsy (p<0.01). Twenty-one patients who performed normally on Steer Clear had 1 accident in 5 ye ars (0.05 accident/driver/5 yr), and in none of these accidents were t hey at fault as drivers, Twenty-five patients who performed poorly on Steer Clear had 5 auto accidents in 5 years (0.20 accident/driver/5 yr ), and in 20% of these accidents they were at fault as drivers, Twenty -one patients who narcolepsy. performed very poorly on Steer Clear had 8 auto accidents in 5 years (0.38 accident/driver/5 yr), and in 38% o f these accidents they were at fault as drivers. These 21 patients who performed very poorly on Steer Clear (hitting>4.5% of obstacles) had a significantly higher auto accident rate than the patients who perfor med normally (hitting<1.8%), We conclude: (1) Patients with sleep apne a or narcolepsy performed more poorly on a test of vigilance, Steer Cl ear, than did control subjects; (2) Impaired vigilance as measured by Steer Clear is associated with a high automobile accident rate in pati ents with either sleep apnea or narcolepsy.