Road traffic crash risk associated with benzodiazepine and z-hypnotic use after implementation of a colour-graded pictogram: a responsibility study

Nonbenzodiazepine hypnotics and police-reported motor vehicle crash risk among older adults: a sequential target trial emulation

Nonbenzodiazepine hypnotics ("Z-drugs") are prescribed for insomnia but might increase the risk of motor vehicle crash (MVC) among older adults through prolonged drowsiness and delayed reaction times. We estimated the effect of initiating Z-drug treatment on the 12-week risk of MVC in a sequential target trial emulation. After linking New Jersey driver licensing and police-reported MVC data to Medicare claims, we emulated a new target trial each week (July 1, 2007, to October 7, 2017) in which Medicare fee-for-service beneficiaries were classified as Z-drug-treated or untreated at baseline and followed for an MVC. We used inverse probability of treatment and censoring-weighted pooled logistic regression models to estimate risk ratios (RRs) and risk differences with 95% bootstrap confidence limits (CLs). There were 257 554 person-trials, of which 103 371 were Z-drug-treated and 154 183 untreated, giving rise to 976 and 1249 MVCs, respectively. The intention-to-treat RR was 1.06 (95% CL, 0.95-1.16). For the per-protocol estimand, there were 800 MVCs and 1241 MVCs among treated and untreated person-trials, respectively, suggesting a reduced MVC risk (RR, 0.83; 95% CL, 0.74-0.92) with sustained Z-drug treatment. Z-drugs should be prescribed to older patients judiciously but not withheld entirely over concerns about MVC risk. This article is part of a Special Collection on Pharmacoepidemiology.

Do crashed drivers need more drug testing? A retrospective analysis of blood samples from hospitalised post-crash drivers in New Zealand

Driving under the influence of alcohol and other drugs is a prominent safety concern in New Zealand and across the world. While alcohol testing is routinely performed for drivers involved in hospitalisation crashes, testing for other drugs is often not undertaken. The present study refers to 530 traffic crashes that occurred from October 2019 to January 2020 on New Zealand roads. The blood samples from 550 drivers who were injured in a crash and were admitted to a hospital (66% of all drivers involved in these crashes), previously tested for drugs and/or alcohol, were retested for a wider range of drugs. Alcohol above the applicable limit was found to be present in 38% of hospitalised drivers, while other drugs of interest were found in 47% of hospitalised drivers. Binary logistic regression was used to predict the presence of drugs of interest for a crashed driver using previous offence data. A driver having at least one prior drink and drug driving offence is 61% more likely to be positive for a drug of interest when involved in a crash. Similarly, a driver having at least one prior non-traffic drug offence is 4.7 times more likely to be positive for at least a drug of interest when involved in a crash. While the presence of a drug or drugs cannot be presumed to have played a role in the occurrence of the crash, this study has provided a unique and comprehensive picture of the presence of various drugs present in New Zealand drivers' blood. It is recommended to consider standardising drug testing on all blood specimens taken in relation to a serious injury or fatal crash. This procedure is not only of interest for information purposes but may importantly inform appropriate charging decisions.

Trajectories of Benzodiazepine Use among Older Adults from a Concordance-with-Guidelines Perspective: A Nationwide Cohort Study

BACKGROUND AND OBJECTIVE

Benzodiazepines (including zolpidem and zopiclone) are often associated with higher-than-recommended intake and durations of use, especially in older adults. The objective of this study was to characterize trajectories of benzodiazepine use according to recommended patterns in older adults, and to assess predictors of the risk of developing each of these trajectories.

METHODS

Using the French Health Insurance database, we constituted a cohort of adults aged ≥ 65 years who initiated benzodiazepines in 2007 and were followed for up to 8 years. Concordance with benzodiazepine use guidelines was assessed on a quarterly basis according to a "concordance-with-guideline score" with values 1-5. Group-based trajectory modeling was then applied as implemented in the Proc Traj procedure in SAS to define guideline-concordant trajectories based on seven baseline patient-centered characteristics: sex, complementary health insurance coverage, treated alcohol and tobacco use disorder, polypharmacy, hospital stay, and registered chronic diseases.

RESULTS

Among 5080 new users (64.1% women, median age 74 years), six trajectories of benzodiazepine use were identified. Three, representing 70% of users, were concordant with guidelines, whereas three implied non-concordant benzodiazepine use for part or all of the benzodiazepine use follow-up. Polymedicated patients were more prone to develop chronic non-guideline-concordant initially guideline-concordant use, whereas those with a history of long-term disease and hospitalization were more likely to develop chronic non-guideline-concordant use. The number of prescribers during the first quarter, number of daily defined doses, use of loperamide, and use of psychostimulants were associated with a higher risk of developing an initial and persistent non-guideline-concordant use. Treatment initiation by a psychiatrist, initial use of World Health Organization (WHO) step-2 opioids and non-benzodiazepine anxiolytics or sedatives were associated with a higher risk of late non-guideline-concordant use.

CONCLUSIONS

Concordance with guidelines varied over time during benzodiazepine use in older adults. A third of these adults will hypothetically follow one of the identified non-guideline-concordant trajectories, consisting of initial and/or late non-guideline concordance. This was associated with modifiable and nonmodifiable factors that clinicians should be aware of for tailoring the monitoring of patients.

Driving anxiety and anxiolytics while driving: Their impacts on behaviour and cognition behind the wheel

Introduction

The interaction between road safety and drivers' mental health is an important issue to take into consideration on transportation and safety research. The present review deals specifically with the link between anxiety and driving activity from two complementary points of view.

Method

A systematic review into primary studies, following the PRISMA statement, was carried out in four databases: Scopus, Web of Science, Transport Research International Documentation and Pubmed. A total of 29 papers were retained. On the one hand, we present a systematic review of research articles exploring the cognitive and behavioural effects of driving anxiety, regardless its onset, when concerned people have to drive. The second goal of the review is to compile the available literature on the influence of legal drugs, which are used to fight against anxiety, on actual driving tasks.

Results

Eighteen papers have been retained for the first question, whose main findings show that exaggerated cautious driving, negative feelings and avoidance are associated with driving anxiety. Most of the conclusions were drawn from self-reported questionnaires and little is known about the effects in situ. Concerning the second question, benzodiazepines are the most studied legal drugs. They affect different attentional processes and could slow reaction times down depending on the population and treatment features.

Conclusions

The two standpoints included in the present work allow us to propose some possible lines of research to study certain aspects that have not been explored in depth about people who either feel apprehensive about driving or who drive under the effects of anxiolytics.

Practical applications

The study on driving anxiety may be crucial to estimate the consequences for traffic safety. Furthermore, it is relevant to design effective campaigns to raise awareness about the issues discussed. To propose standard evaluations of driving anxiety and exhaustive research works to find out the extent of anxiolytics use are also important to be considered for traffic policies.

Categorization and labeling systems concerning driving-impairing medicines: A scoping review

OBJECTIVE

Classification systems concerning driving-impairing medicines can help healthcare providers identify medicinal drugs with no or the least impairing effects and inform patients of the potential risks of certain medicines to safe driving. This study aimed to comprehensively assess the characteristics of classifications and labeling systems regarding driving-impairing medicines.

METHODS

Google Scholar and several databases, including PubMed, Scopus, Web of Science, EMBASE, safetylit.org, and TRID were searched to identify the relevant published material. The retrieved material was assessed for eligibility. Data extraction was done to compare the categorization/labeling systems concerning driving-impairing medicines in terms of characteristics such as the number of categories, description of each category, and description of pictograms.

RESULTS

After screening 5,852 records, 20 studies were selected for inclusion in the review. This review identified 22 categorization/labeling systems regarding medicines and driving. Classification systems had different characteristics, but most of them were designed based on the graded categorization system described by Wolschrijn. Initially, categorization systems had seven levels, but later the medicine impacts were summarized into 3 or 4 levels.

CONCLUSIONS

Although different categorization/labeling systems regarding driving-impairing medicines are available, the most effective systems in changing driver's behavior are the simple and understandable ones. Besides, health care providers should consider patient's socio-demographic features when informing them about driving under the influence.

Association between road traffic accidents and drugs belonging to the antiseizure medications class: A pharmacovigilance analysis in VigiBase

AIMS

Due to their central mechanism of action, antiseizure medications (ASMs) could lead to adverse effects likely to impair driving skills. Their extended use to neuropsychiatric disorders makes it a class of drugs to monitor for their road traffic accidental (RTA) potential. We aimed to assess the reporting association between ASMs and RTAs using the World Health Organization pharmacovigilance database (VigiBase).

METHODS

We performed a disproportionality analysis to compute adjusted reporting odds ratios to evaluate the strength of reporting association between ASMs and RTAs. A univariate analysis using the reporting odds-ratio was used to assess drug-drug interactions between ASMs and RTAs.

RESULTS

There were 1 341 509 reports associated with at least 1 ASM in VigiBase of whom 2.91‰ were RTAs reports. Eight ASMs were associated with higher reporting of RTAs compared to others (ranging from 1.35 [95% confidence interval 1.11-1.64] for lamotrigine to 4.36 [95% confidence interval 3.56-5.32] for cannabis). Eight significant drug-drug interactions were found between ASMs and the onset of RTA, mainly involving CYP450 induction.

CONCLUSION

A significant safety signal between RTAs and some ASMs was identified. Association of several ASMs might further increase the occurrence of RTA. ASMs prescription in patients with identified risk factors of RTA should be considered with caution. Study number: ClinicalTrials.gov, NCT04480996.

Use of psychotropic medication and risk of road traffic crashes: a registry-based case-control study in Denmark, 1996-2018

RATIONALE

Use of psychotropics is relatively prevalent amongst motor vehicle drivers because mobility is also important for persons suffering from psychiatric illness. However, medication side effects may increase the likelihood of being involved in traffic crashes.

OBJECTIVES

This study aimed to assess the association between the use of four types of medication (antipsychotics, benzodiazepines and z-hypnotics, antidepressants and stimulants of ADHD treatment) and the risk of traffic crashes, in general, and single crashes subsequently.

METHOD

We conducted a case-control study of data from 130,000 drivers involved in traffic crashes with personal injury and prescription data from all of Denmark during the period 1996-2018.

RESULTS

For antipsychotics, we found odds ratios of 0.86 and 1.29 for traffic crashes and single crashes, respectively; for benzodiazepines and z-hypnotics, 1.29 and 2.49, respectively; for antidepressants, 1.30 and 2.25, respectively; and for stimulants of ADHD treatment, 1.62 and 1.95, respectively. All p values were below 0.001.

CONCLUSIONS

Based on our results on twofold increased risks of single crashes and moderately increased risks in persons with ADHD, it might seem tempting to ban psychotropic medication in traffic. Conversely, we accept increased risks of traffic crashes in young drivers and in the physically disabled with special aids and, to some extent, with exposure to alcohol. In the end, it is the authorities who must review the evidence and decide whether to prohibit (some types of) psychotropic medication in traffic. Finally, underlying disease and not the drug may increase the risk of being involved in a traffic crash.

Trends in the prescription of drugs used for insomnia: an open-cohort study in Australian general practice, 2011-2018

BACKGROUND

Despite an increase in the prevalence of sleep problems, few studies have investigated changes in the prescribing of drugs that are often used to manage insomnia.

AIM

To explore changes in the pattern of benzodiazepine (BZD), Z-drug (zolpidem, zopiclone), and non-BZD prescriptions.

DESIGN AND SETTING

Open-cohort study comprising 1 773 525 patients (55 903 294 consultations) who attended one of 404 Australian general practices at least three times in two consecutive years between 2011 and 2018.

METHOD

Data were extracted from MedicineInsight, a database of 662 general practices in Australia. Prescription rates per 1000 consultations, the proportion of repeat prescriptions above recommendations, and the proportion of prescriptions for patients with a recent (within 2 years) recorded diagnosis of insomnia were analysed using adjusted regression models.

RESULTS

Rates of BZD, Z-drug, and non-BZD prescriptions were 56.6, 4.4, and 15.5 per 1000 consultations in 2011 and 41.8, 3.5, and 21.5 per 1000 consultations in 2018, respectively. Over the whole study period, temazepam represented 25.3% of the prescriptions and diazepam 21.9%. All BZD and zolpidem prescriptions declined over the whole study period (annual change varying from -1.4% to -10.8%), but non-BZD and zopiclone prescriptions increased in the same period (annual change 5.0% to 22.6%). Repeat prescriptions that exceeded recommended levels remained at <10% for all medications, except melatonin (64.5%), zolpidem (63.3%), zopiclone (31.4%), and alprazolam (13.3%). In 2018, >50% of Z-drug and melatonin prescriptions were for patients with insomnia. There was an annual increase of 0.8-5.9% in the proportion of prescriptions associated with a recently recorded diagnosis of insomnia.

CONCLUSION

Overall, BZD prescriptions in Australia declined between 2011 and 2018. However, the prescription of some of these drugs increased for patients with a recently recorded diagnosis of insomnia. This is concerning because of the potential adverse effects of these medications and the risk of dependence.

Patterns of Benzodiazepine Use and Excess Risk of All-Cause Mortality in the Elderly: A Nationwide Cohort Study

INTRODUCTION

Despite the risks associated with their use, benzodiazepines remain used more widely than wisely. In this context, a better understanding of how their patterns of use can be associated with an increased risk of death appears essential. Indeed, the studies that investigated this association so far are inconsistent and question the influence of potential biases.

OBJECTIVE

The objective of this study was to investigate the association of various patterns of benzodiazepine use with all-cause mortality.

METHODS

A nationwide cohort of non-prevalent benzodiazepine users aged ≥ 65 years was identified using French healthcare insurance system claims databases. Exposure to benzodiazepines considered short-term, chronic (defined as a cumulated ≥ 6-month period over the previous 12 months), ongoing, and discontinued use. Using a Cox model, adjusted hazard ratios for all-cause mortality were estimated according to benzodiazepine patterns of use; exposure and confounders were treated as time-dependent variables.

RESULTS

In the cohort of 54,958 individuals aged ≥ 65 years, adjusted hazard ratios for all-cause mortality and benzodiazepines were 2.26 (95% confidence interval 1.96-2.61) for short-term use, 3.86 (3.04-4.90) for chronic use-discontinued, and 3.05 (2.17-4.29) for chronic use-ongoing. At age 80 years, these were 1.62 (1.48-1.79), 2.00 (1.82-2.19) and 1.13 (1.02-1.26), respectively. Adjusted hazard ratios show similar decreases with age for all patterns of benzodiazepine use.

CONCLUSIONS

These findings confirm the existence of an excess risk of mortality associated with benzodiazepine use and provide pattern- and age-specific estimates. Higher risks were observed for patients aged < 80 years, short-term use, or chronic use recently interrupted. If the two latter can relate to an indication bias, the associations found for ongoing chronic use and short-term use conversely support a potential causal hypothesis.

Road traffic crash characteristics of drivers who take prescription medicines that carry a risk to driving

BACKGROUND

The specific features of crashes involving an alcohol-intoxicated driver have been extensively characterized, but no such data are available for crashes involving a driver who has used a prescription medicine, which could help to plan and target prevention and control initiatives. This study aimed to describe the characteristics of crashes involving drivers under the influence of prescription medicines.

METHODS

We took advantage of CESIR, a French record linkage study for which data were extracted and matched from three French national databases: police reports, the national police database of injurious crashes and the national health care insurance database (HCI database). The drivers included in the study were those involved in an injurious road crash in France from July 1, 2005 to December 31, 2015, whose national identity number, date of birth and sex allowed matching. Prescription medicines considered were those with the two highest levels of warning.

RESULTS

Similar crash profiles were found when drivers used alcohol or medicines, particularly with respect to injury severity, type of vehicle, type of collision, type of road and cross-track profile. Alcohol-related crashes were over-represented during weekends and in low-density areas and medicine-related crashes were over-represented during weekdays and in cities of fewer than 300 000 inhabitants. While a much higher strength of association with responsibility was found for alcohol than for medicines, the proportion of crashes with drivers using medicines was twice as high as crashes with drivers using alcohol.

CONCLUSION

The lower risk carried by medicines is therefore in part compensated by a higher prevalence of use, making medicines one of the hidden factors of road risk. Characterizing these crashes will therefore be useful to better focus road safety intervention on the prevention of driving under the influence of psychotropic medicines.

Do hypnotics increase the risk of driving accidents or near miss accidents due to hypovigilance? The effects of sex, chronic sleepiness, sleep habits and sleep pathology

Driving accidents due to hypovigilance are common but the role of hypnotics is unclear in patients suffering from sleep disorders. Our study examined factors influencing accidents and near miss accidents attributed to sleepiness at the wheel (ANMAS). Using data from an online questionnaire aimed at patients with sleep disorders, we analysed the associations between ANMAS, sociodemographic data, symptoms of sleep disorders, severity of insomnia (Insomnia Severity Index (ISI)) symptoms of anxiety and depression (Hospital Anxiety and Depression scale with depression (HADD) and anxiety (HADA) subscales), chronic sleepiness (Epworth sleepiness scale ESS), hypnotic use and information about sleep habits. Hypnotics were hierarchically grouped into Z-drugs, sedative medication, melatonin and over the counter (OTC) alternative treatments. Of 10802 participants; 9.1% reported ANMAS (Men 11.1% women 8.3%) and 24.4% took hypnotics (Z-drugs 8.5%, sedative medication 8%, melatonin 5.6% and alternative treatments 2.5%). Logistic regression analysis identified the following risk factors for ANMAS: moderate (OR 2.4; CI: 2.10-2.79) and severe sleepiness (ESS OR 5.66; CI: 4.74-6.77), depression (HADD OR 1.2; CI: 1.03-1.47), anxiety (HADA OR 1.2;CI: 1.01-1.47), and insufficient sleep (OR1.4; CI: 1.2-1.7). Hypnotics were not associated with an increased risk of ANMAS in patients suffering from insomnia. Risk factors varied according to sex: in females, sex (OR 0.; CI: 0.55-0.74), mild insomnia (OR 0.5; CI: 0.3-0.8) and use of alternative treatments (OR 0.455, CI:0.23-0.89) were protective factors and risk was increased by sleepiness, sleep debt, social jetlag, caffeine use, anxiety and depression. In men no protective factors were identified: sleepiness, sleep debt, and severe insomnia were associated with an increased risk of ANMAS. In clinical practice, all patients with daytime sleepiness and men with severe insomnia should be counselled concerning driving risk and encouraged to avoid sleep debt.

Factors associated with serious vehicular accidents: A cross-sectional study in hospital emergency rooms

AIMS

Pictograms on medicine boxes warn of potential drug-related driving hazard; we studied their association with serious accidents.

METHODS

Prospective study in emergency departments of the hospitals in Bordeaux and Périgueux (France), of drivers with serious (admitted at least 24 hours) or nonserious vehicular accidents. Minors, passengers, pedestrians or subjects incapable of answering an interview were excluded. Interviews ascertained driver and accident characteristics, use of drugs with or without pictograms, use of alcohol and abuse substances, sleepiness, distractions, and mind wandering at the time of the accident, RESULTS: Between 18 October 2016 and 26 December 2018, 1200 of the 6212 drivers admitted to the hospital emergency rooms, 741 nonserious, 459 serious, were interviewed. Serious accidents were associated with male sex (odds ratio 1.89, 95% confidence interval [1.36-2.64]), age above 60 years (3.64 [2.21-6.00]), driving on local roads (3.34 [2.34-4.76]), driving a motorcycle (3.39 [2.29-5.00]), having drunk alcohol within 6 hours (2.89 [1.85-4.51]) and using a drug with a pictogram during the 24 hours previous to the accident (1.57 [1.06-2.32]). From 207 police reports, 101 drivers were not responsible, and 106 were responsible, associated with age below 40 years, driving in overcast or rainy weather (2.62 [1.29-5.33]), on local roads (3.89 [1.90-7.95]), and use of at least 1 pictogram drug in the previous week (3.12 [1.31-7.41]).

CONCLUSION

The known risks of alcohol and pictogram drugs, of riding motorcycles and using local roads were confirmed. As measured, behavioural sleepiness did not predict accidents.

Trends in benzodiazepine anxiolytics and z-hypnotics use among French drivers involved in road traffic crashes from 2005 to 2015: a responsibility case-control study

Background

In France, benzodiazepine anxiolytics and z-hypnotics (zolpidem and zopiclone) account for the largest share of road traffic crash risk attributable to exposure to prescription drugs. The aim of this study was to monitor the evolution of the use of these prescription drugs and their association with crash risk over a period that began before the implementation of a color-graded pictogram system printed on prescription drug boxes.

Methods

Data from three French national databases were extracted and linked: the national health care insurance database, police reports, and the national police database of injurious crashes. Drivers involved in an injurious crash in France, from July 2005 to December 2015, and identified by their national identifier were included. The association with crash risk was estimated using a responsibility analysis comparing the use of benzodiazepines and z-hypnotics among drivers responsible or not for the crash.

Results

A total of 97,936 responsible and 103,522 non-responsible drivers involved in an injurious crash were included. The proportion of drivers exposed to benzodiazepine anxiolytics or z-hypnotics remained stable among responsible and non-responsible drivers. Among controls from the general population, the proportion of exposed individuals tended to increase. The association with crash risk remained almost constant over the study period. The odds-ratio for benzodiazepines ranged between 1.42 [1.24–1.62] at the beginning of the study period and 1.27 [1.09–1.47] at the end.

Conclusion

Given the increase in exposure in the control group from the general population, the stability of exposure for responsible and non-responsible drivers can be interpreted as a relative effectiveness of the pictogram on driver exposure levels. On the other hand, while the intrinsic effect of a prescription drug cannot be modified, a decrease in risk could have been expected if drivers adapted their behavior as promoted by the pictogram. Our results therefore suggest that no significant change occurred in driving behaviors or consumption patterns.

Cannabis, alcohol and fatal road accidents

Introduction

This research aims to estimate the relative risks of responsibility for a fatal accident linked to driving under the influence of cannabis or alcohol, the prevalence of these influences among drivers and the corresponding attributable risk ratios. A secondary goal is to estimate the same items for three other groups of illicit drugs (amphetamines, cocaine and opiates), and to compare the results to a similar study carried out in France between 2001 and 2003.

Methodology

Police procedures for fatal accidents in Metropolitan France during 2011 were analyzed and 300 characteristics encoded to provide a database of 4,059 drivers. Information on alcohol and four groups of illicit drugs derived from tests for positivity and potential confirmation through blood analysis. The study compares drivers responsible for causing the accident, that is to say having directly contributed to its occurrence, to drivers involved in an accident for which they were not responsible, and who can be assimilated to drivers in general.

Results

The proportion of persons driving under the influence of alcohol is estimated at 2.1% (95% CI: 1.4–2.8) and under the influence of cannabis at 3.4% (2.9%-3.9%). Drivers under the influence of alcohol are 17.8 times (12.1–26.1) more likely to be responsible for a fatal accident, and the proportion of fatal accidents which would be prevented if no drivers ever exceeded the legal limit for alcohol is estimated at 27.7% (26.0%-29.4%). Drivers under the influence of cannabis multiply their risk of being responsible for causing a fatal accident by 1.65 (1.16–2.34), and the proportion of fatal accidents which would be prevented if no drivers ever drove under the influence of cannabis is estimated at 4.2% (3.7%-4.8%). An increased risk linked to opiate use has also been found to be significant, but with low prevalence, requiring caution in interpreting this finding. Other groups of narcotics have even lower prevalence, and the associated extra risks cannot be assessed.

Conclusion

Almost a decade separates the present study from a similar one previously conducted in France, and there have been numerous developments in the intervening years. Even so, the prevalence of drivers responsible for causing fatal accidents under the influence of alcohol or narcotics has stayed remarkably stable, as have the proportion of fatal accidents which could in theory be prevented if no drivers ever exceeded the legal limits. The overall number of deaths from traffic accidents has dropped sharply during this period, and the number of victims attributable to alcohol and/or cannabis declined proportionally. Alcohol remains the main problem in France. It is just as important to note that one in two drivers considered to be under the influence of cannabis was also under the influence of alcohol. With risks cumulating between the two, it is particularly important to point out the danger of consuming them together.

Prescription medicine use by pedestrians and the risk of injurious road traffic crashes: A case-crossover study

BACKGROUND

While some medicinal drugs have been found to affect driving ability, no study has investigated whether a relationship exists between these medicines and crashes involving pedestrians. The aim of this study was to explore the association between the use of medicinal drugs and the risk of being involved in a road traffic crash as a pedestrian.

METHODS AND FINDINGS

Data from 3 French nationwide databases were matched. We used the case-crossover design to control for time-invariant factors by using each case as its own control. To perform multivariable analysis and limit false-positive results, we implemented a bootstrap version of Lasso. To avoid the effect of unmeasured time-varying factors, we varied the length of the washout period from 30 to 119 days before the crash. The matching procedure led to the inclusion of 16,458 pedestrians involved in an injurious road traffic crash from 1 July 2005 to 31 December 2011. We found 48 medicine classes with a positive association with the risk of crash, with median odds ratios ranging from 1.12 to 2.98. Among these, benzodiazepines and benzodiazepine-related drugs, antihistamines, and anti-inflammatory and antirheumatic drugs were among the 10 medicines most consumed by the 16,458 pedestrians. Study limitations included slight overrepresentation of pedestrians injured in more severe crashes, lack of information about self-medication and the use of over-the-counter drugs, and lack of data on amount of walking.

CONCLUSIONS

Therapeutic classes already identified as impacting the ability to drive, such as benzodiazepines and antihistamines, are also associated with an increased risk of pedestrians being involved in a road traffic crash. This study on pedestrians highlights the necessity of improving awareness of the effect of these medicines on this category of road user.

Road traffic crash risk associated with benzodiazepine and z-hypnotic use after implementation of a colour-graded pictogram: a responsibility study

AIMS

To assess potential change in medicine exposure and association with the risk of road traffic crash across a time period that started before the implementation of a grading system warning of the effect of medicine on driving performance.

METHODS

Data from three French national databases were extracted and matched: the national health care insurance database, police reports and the national police database of injurious crashes. Drivers involved in such crashes in France, from July 2005 to December 2011 and identified by their national identifier, were included. Association with the risk of crash was estimated using a case-control analysis comparing benzodiazepine and z-hypnotic use among drivers responsible or not responsible for the crash.

RESULTS

Totals of 69 353 responsible and 73 410 non-responsible drivers involved in an injurious crash were included. Exposure to benzodiazepine anxiolytics was associated with an increased risk of being responsible for a road traffic crash during the pre-intervention period (OR = 1.42 [1.24-1.62]). The association disappeared in the post-intervention period, but became significant again thereafter. The risk of being responsible for a crash increased in users of z-hypnotics across the study period.

CONCLUSIONS

Our results question the efficacy of the measures implemented to promote awareness about the effects of medicines on driving abilities. Prevention policies relating to the general driving population, but also to healthcare professionals, should be reviewed.