The impact of medicinal drugs on traffic safety: a systematic review of epidemiological studies.
OBJECTIVE
To evaluate the quality of epidemiological research into effects of medicinal drugs on traffic safety and the current knowledge in this area.


METHODS
The bibliographic search was done in Medline electronic database using the keywords: ((accident* or crash*) and traffic and drug*) leading to 1141 references. Additional references were retrieved from the Safetylit website and the reference lists of selected studies. Original articles published in English or French, between 1 April 1979 and 31 July 2008, were considered for inclusion. We excluded descriptive studies, studies limited to alcohol or illicit drug involvement and investigations of injuries other than from traffic crashes. Studies based on laboratory tests, driving simulators or on-the-road driving tests were also excluded. Eligible studies had to evaluate the causal relationship between the use of medicinal drugs and the risk of traffic crashes. Study quality was assessed by two independent experts, according to a grid adapted from the strengthening the reporting of observational studies in epidemiology (STROBE) statement.


RESULTS
Twenty two studies of variable methodological quality were included. Definition of drug exposure varied across studies and depended on the data sources. Potential confounding due to the interaction between the effects of the medicinal drug and disease-related symptoms was often not controlled. The risk of motor-vehicle crashes related to benzodiazepines has been amply studied and demonstrated. Results for other medicinal drugs remain controversial.


CONCLUSIONS
There is a need for large studies, investigating the role of individual substances in the risk of road traffic crashes.
Equipe Avenir prévention et prise en charge des traumatismes, Centre de recherche INSERM U897 Epidémiologie et Biostatistiques, Université Victor Segalen Bordeaux 2, France. ludivine.orriols@isped.u-bordeaux2.fr
Ludivine
L
Orriols
Louis-Rachid
LR
Salmi
Pierre
P
Philip
Nicholas
N
Moore
Bernard
B
Delorme
Anne
A
Castot
Emmanuel
E
Lagarde
D000063:Accidents, Traffic / Q000706:statistics & numerical data*; D001569:Benzodiazepines / Q000009:adverse effects; D015982:Bias; D064420:Drug-Related Side Effects and Adverse Reactions; D015340:Epidemiologic Research Design; D006801:Humans; D016017:Odds Ratio; D018570:Risk Assessment; D012307:Risk Factors
D001569:Benzodiazepines