|
Abstract
|
Drugs affecting driving ability (DADAs) directly1-4 or by indicating at-risk diseases5 are classified in a 4-level standardized classification associated with a graded pictogram.6 A study in the French police database of crashes and in the national health care database showed an increased risk of being responsible in drivers exposed to level 2 or level 3 drugs7 but did not include information on sleepiness, the use of illicit drugs, or other occupational factors.
Our objective was to describe the factors associated with being responsible for a serious road crash and patient-reported use of labeled medicines.
Methods
All adult drivers hospitalized at least 24 hours (ie, a serious crash) in Limoges, Bordeaux, or Toulouse, France, in 2007 through 2009 were queried using structured questionnaires8,9 about the circumstances of the crash, use of medicines and drugs, and other risk factors (eg, alcohol, sleepiness at the wheel, sleep apnea, or concomitant diseases). Blood alcohol content was abstracted from patient files. Police reports provided responsibility for the crash. Exposure to risk factors, including medication, was compared between responsible and nonresponsible drivers. The Regional Committee for the Protection of Persons and the National Committee on Informatics and Liberties approved the study. All patients gave informed consent.
Results
A total of 679 patients was included; their mean (SD) age was 36.5 (14.7) years, 85.0% were younger than 55 years, and 83.0% were male. Of these, 53.3% were driving a motorcycle vs a car for 33.1% and a bicycle for 10.3%. Seventy-seven percent of crashes occurred between 6:00 AM and 8:00 PM. Night crashes were 4 times more common in those who were 18 to 29 years old (28.1%) and twice more common in those who were 30 to 54 years old (14.6%) than those 55 years or older (7.1%; P < .05). A total of 49.0% had used at least 1 medication during the previous week, and 31.5% had done so during the previous 24 hours (11.0% had used a central nervous system drug, and 9% had used a cardiovascular drug). Of these, half took at least 1 DADA. Of 352 patients with blood alcohol concentrations (BAC), 68.5% had a BAC of less than 0.5 g/L, 1.7% had a BAC of 0.5 to 0.8 g/L, and 29.8% had a BAC greater than 0.8 g/L. A total of 28.9% of drivers admitted drinking alcohol on the day of the crash, and 20.2% had done so in the 6 hours preceding the crash. Concordance between reporting alcohol use on the day of the crash and a BAC of at least 0.5 g/L was good (κ = 0.63). More men reported alcohol use on the day of the crash (31.7%) than women (14.8%); 2.5% of drivers reported use of controlled substances within 6 hours before the crash, mostly cannabis; and 7% reported concomitant use of medicines, substances, and/or alcohol within 24 hours before the crash.
Almost 50% of drivers had slept over 7 hours every night during the week before the crash, and 59.5% had slept 7 to 9 hours the night before the crash. The risk of sleepiness at the wheel was high in 3.8%, with high or medium risk of sleepiness more common in men (27.7%) than in women (17.4%; P = .02), and in younger drivers (29.5% in those who were 18-29 years old vs 26.3% in those 30-54 years old and 14.3% in those ≥55 years; P = .01). Most drivers reported being perfectly alert immediately before the crash; 11.8% were alert, 6.5% slightly drowsy, 1.8% were fighting to stay awake, and 1.0% were no longer fighting or were asleep. Twenty-two of 524 patients had a high risk of sleep apnea on the Berlin Sleep Questionnaire.
Responsibility was established in 355 drivers (52.3%). There were no differences for sex, age, time of crash, delay between crash and admission to hospital, inclusion in the study, or data acquisition between patients with or without a police report, but there were fewer bicycle crashes (6.2% vs 14.9%), single-vehicle crashes (28.0% vs 69.0%) reported, and crashes on roundabouts and intersections (17.0% vs 28.0%). Information on BAC at admission was more often found (59.5% vs 44.7%; P < .001); 207 drivers were considered responsible. Multivariate analysis found that age 18 to 29 years, driving a car, drinking alcohol, and sleepiness at the wheel were independent predictors of being responsible for the crash (Table). Use of any medication was associated with a lower risk of being responsible. Compared with non-DADAs, the use of DADAs was associated with a slightly increased risk (hazard ratio, 1.24; 95% CI, 0.56-2.77).
Comment
In conclusion, the main factors associated with being responsible for a crash resulting in serious injury were younger age and driving cars, but more important were alcohol ingestion and sleepiness at the wheel, which are synergic.9 We found no clear effect of DADAs. Sleepiness carried almost as much risk as alcohol ingestion. If alcohol use while driving can be reduced by legal interdictions and punishment correlated with BAC, the fight against sleepiness at the wheel can be addressed only by information and education. Coercion might be difficult to implement: could, for instance, a Stanford sleepiness test be administered by police forces and drivers fined or forbidden to drive if they fail?
Keywords: Cannabis impaired driving; DUID; Ethanol impaired driving
Language: en |