The 10-year risk of verified motor vehicle crashes in relation to physiologic sleepiness.
OBJECTIVE
The purpose of this study was to determine the risk of DMV documented crashes as a function of physiological sleepiness in a population-based sample.


METHODS
24-hour laboratory assessment (nocturnal polysomnogram and daytime MSLT) and 10-year crash rate based on DMV obtained accident records.


METHODS
618 individuals (mean age = 41.6 +/- 12.8; 48.5% male) were recruited from the general population of southeastern Michigan using random-digit dialing techniques.


RESULTS
Subjects were divided into 3 groups based on their average MSLT latency (in minutes) as follows: excessively sleepy, 0.0 to < or = 5.0 (n = 69); moderately sleepy, 5.0 to < or = 10.0 (n = 204); and alert, > 10 (n = 345). Main outcome measures were DMV data on accidents from 1995-2005. Rates for all accidents in the 3 MSLT groups were: excessively sleepy = 59.4%, moderately sleepy = 52.5%, alert = 47.3%. Excessively sleepy subjects were at significantly greater risk of an accident over the 10-year period compared to alert subjects. A similar relation was observed when we limited the database to those accident victims with severe injury (excessively sleepy = 4.3%, moderately sleepy = 0.5%, alert = 0.6%; P = 0.028). When the victim was the only occupant of the car, subjects in the lowest MSLT group (highest sleepiness) had the greatest crash rate compared with alert individuals (excessively sleepy = 52.2%, moderately sleepy = 42.2%, alert = 37.4%; P = 0.022).


METHODS
N/A.


CONCLUSIONS
These data demonstrate that the MSLT, a physiological measure of sleepiness, is predictive of an increased risk of DMV documented automotive crashes in the general population.
Drake
Christopher
C
Sleep Disorders and Research Center, Henry Ford Hospital, 2799 West Grand Blvd, CFP3, Detroit, MI 48202, USA. cdrake1@hfhs.org
Roehrs
Timothy
T
Breslau
Naomi
N
Johnson
Eric
E
Jefferson
Catherine
C
Scofield
Holly
H
Roth
Thomas
T
D000063:Accidents, Traffic / Q000706:statistics & numerical data*; D000293:Adolescent; D000328:Adult; D006970:Disorders of Excessive Somnolence / Q000175:diagnosis* / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D008824:Michigan / Q000453:epidemiology; D008875:Middle Aged; D017286:Polysomnography / Q000379:methods / Q000706:statistics & numerical data; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012307:Risk Factors; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D055815:Young Adult