Health conditions and the risk of home injury in French adults: results from a prospective study of the MAVIE cohort.

BACKGROUND: Home injury (HI) is a significant cause of mortality and morbidity in adults of all ages. Health conditions significantly impact HI among old adults, but little is known for other adults. STUDY DESIGN: Prospective cohort study. OBJECTIVE: We assessed the associations between health-related factors and HI's risk in a French study, the MAVIE (Mutualistes pour la recherche contre les Accidents de la VIE courante) cohort. METHODS: Poisson mixed models were fitted using health-related data information (diseases, treatments and disabilities) at baseline and the number of injuries prospectively recorded during the follow-up, adjusting for significant sociodemographics and exposure to a range of home activities. Attributable fractions were estimated based on risk ratio (RR) estimations measured in the fully adjusted models. RESULTS: A total of 6146 dwelling adults aged 15 or older were followed up for 5.1 years on average. Vertigo or dizziness (RR=2.36, 95% CI 1.06 to 5.01) and sciatica or back pain (RR=1.49, 95% CI 1.08 to 2.05) were independently associated with an increased risk of HI. These two groups of conditions showed the most significant associations among people aged 15-49, whereas musculoskeletal diseases other than rachialgias and arthropathies were the most significant health-related risk factor in people aged 50 and older. Sciatica or back pain represented the highest burden of HIs in overall adults (8%) and among people aged 15-49 (12%). CONCLUSION: Our results suggest that adults with musculoskeletal disorders and vertigo or dizziness symptoms have a higher risk of HI, regardless of age.

Chronic medical conditions and their association with crash risk and changes in driving habits: a prospective study of the GAZEL cohort.

OBJECTIVES: To assess crash risk and driving habits associated with chronic medical conditions among drivers entering old age. DESIGN: Prospective cohort study. SETTING: French cohort GAZEL. PARTICIPANTS: 12 460 drivers in the analysis of road traffic crash, among whom 11 670 completed the follow-up period (2007-2014). We assessed driving cessation among 11 633 participants over the same period, and mileage and driving avoidance among the 4973 participants who returned a road safety questionnaire in 2015. MAIN OUTCOME MEASURES: Yearly occurrence of at least one road crash as a driver; time to driving cessation; mileage; driving avoidance: at night, with bad weather, in heavy traffic, with glare conditions, over long distances. RESULTS: Several potentially risky conditions (angina, myocardial infarction, coronary disease; stroke; nephritic colic, urinary stones; glaucoma) were associated with lower mileage and/or driving avoidance and did not increase crash risk. Neither driving avoidance nor lower mileage was found for other conditions associated with an increased crash risk: hearing difficulties (adjusted OR 1.19, 95% CI 1.06 to 1.34); joint disorders (1.17, 95% CI 1.06 to 1.30). Depression, anxiety and stress was associated with an increased crash risk (1.23, 95% CI 1.01 to 1.49) despite increased driving avoidance. Parkinson's disease was associated with driving cessation (adjusted HR 32.61, 95% CI 14.21 to 65.17). CONCLUSIONS: Depending on their condition, and probably on the associated risk perception, drivers entering old age report diverse driving habits. For example, hearing difficulties is a frequent condition, rarely considered a threat to road safety, and nonetheless associated with an increased crash risk.

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.

Sparse conditional logistic regression for analyzing large-scale matched data from epidemiological studies: a simple algorithm.

This paper considers the problem of estimation and variable selection for large high-dimensional data (high number of predictors p and large sample size N, without excluding the possibility that N < p) resulting from an individually matched case-control study. We develop a simple algorithm for the adaptation of the Lasso and related methods to the conditional logistic regression model. Our proposal relies on the simplification of the calculations involved in the likelihood function. Then, the proposed algorithm iteratively solves reweighted Lasso problems using cyclical coordinate descent, computed along a regularization path. This method can handle large problems and deal with sparse features efficiently. We discuss benefits and drawbacks with respect to the existing available implementations. We also illustrate the interest and use of these techniques on a pharmacoepidemiological study of medication use and traffic safety.

Variable selection on large case-crossover data: application to a registry-based study of prescription drugs and road traffic crashes.

PURPOSE: In exploratory analyses of pharmacoepidemiological data from large populations with large number of exposures, both a conceptual and computational problem is how to screen hypotheses using probabilistic reasoning, selecting drug classes or individual drugs that most warrant further hypothesis testing. METHODS: We report the use of a shrinkage technique, the Lasso, in the exploratory analysis of the data on prescription drugs and road traffic crashes, resulting from the case-crossover matched-pair interval approach described by Orriols and colleagues (PLoS Med 2010; 7:e1000366). To prevent false-positive results, we consider a bootstrap-enhanced version of the Lasso. To highlight the most stable results, we extensively examine sensitivity to the choice of referent window. RESULTS: Antiepileptics, benzodiazepine hypnotics, anxiolytics, antidepressants, antithrombotic agents, mineral supplements, drugs used in diabetes, antiparkinsonian treatment, and several cardiovascular drugs showed suspected associations with road traffic accident involvement or accident responsibility. CONCLUSION: These results, in relation to other findings in the literature, provide new insight and may generate new hypotheses on the association between prescription drugs use and impaired driving ability.

Comparing responsible and non-responsible drivers to assess determinants of road traffic collisions: time to standardise and revisit.

OBJECTIVES: In 1994, Robertson and Drummer formalised the responsibility analysis as an alternative to case-control studies in the study of road traffic crashes. Our objective was to assess whether published responsibility studies respected standards defining adequate case-control studies. SETTING: Using Web of Science, Scopus and Google Scholar, we identified responsibility studies indexed until October 2013, which cited Robertson and Drummer's paper. After reviewing titles, abstracts and reference lists, we selected original studies comparing responsible and non-responsible drivers, published in peer-reviewed journals or proceedings. DATA AND ANALYSIS: We applied a grid to judge the conformity of the responsibility assessment to the original definition, and whether methods addressing representativeness of selection, accuracy of measures of exposures, confounding variables, and power met standards defining adequate case-control studies. RESULTS: Of 205 titles, we identified 20 papers. Methods of responsibility assessment were the original in three papers. Variations across studies concerned the number of mitigating factors included, or the use of questionnaires rather than police data (n=3). The ratio responsible/non-responsible drivers varied from 0.90 to 5.31, due to major variations in sampling methods, threshold selection, and data completeness. Selection or measurement issues were discussed in 13 papers, but seldom addressed in the design. A comparison of confounding factors in responsible and non-responsible drivers was presented in five papers. CONCLUSIONS: Basic requirements of case-control studies are often not or not clearly met in responsibility studies. There is a need to revisit the method and to adapt existing publication standards to the way responsibility studies are reported.

Prescription of antidepressants and the risk of road traffic crash in the elderly: a case-crossover study.

AIM: To investigate the impact of antidepressants on the risk of road traffic crash in the elderly. METHODS: Reports from the Universal Quebec Automobile Insurance Agency database were matched with data on antidepressant prescription from the Quebec Health Insurance Agency. The case-crossover analysis consisted in comparing exposure during a period immediately before the crash with exposure during earlier periods, for the same subject. RESULTS: One hundred and nine thousand four hundred and six drivers between 66 and 84 years of age involved in a traffic crash between 1988 and 2000 were included. Two thousand nine hundred and nineteen (2.7%) were exposed to an antidepressant on the day of the crash. Case-crossover analysis found an increased risk of crash in drivers with a prescription of antidepressants before their crash when compared with a prescription of antidepressants 4 to 8 months before the crash (OR = 1.19, 95% CI 1.08, 1.30 to 1.42. 95% CI 1.30, 1.55). With the most recent control periods, results were not significant. CONCLUSION: A patient's mental state is probably more similar between two periods that are close to each other than up to 8 months before. Consequently, the risk of crash is likely to be linked to symptoms of depression.

Prescription-drug-related risk in driving: comparing conventional and lasso shrinkage logistic regressions.

BACKGROUND: Large data sets with many variables provide particular challenges when constructing analytic models. Lasso-related methods provide a useful tool, although one that remains unfamiliar to most epidemiologists. METHODS: We illustrate the application of lasso methods in an analysis of the impact of prescribed drugs on the risk of a road traffic crash, using a large French nationwide database (PLoS Med 2010;7:e1000366). In the original case-control study, the authors analyzed each exposure separately. We use the lasso method, which can simultaneously perform estimation and variable selection in a single model. We compare point estimates and confidence intervals using (1) a separate logistic regression model for each drug with a Bonferroni correction and (2) lasso shrinkage logistic regression analysis. RESULTS: Shrinkage regression had little effect on (bias corrected) point estimates, but led to less conservative results, noticeably for drugs with moderate levels of exposure. Carbamates, carboxamide derivative and fatty acid derivative antiepileptics, drugs used in opioid dependence, and mineral supplements of potassium showed stronger associations. CONCLUSION: Lasso is a relevant method in the analysis of databases with large number of exposures and can be recommended as an alternative to conventional strategies.

Analysis of multiple exposures in the case-crossover design via sparse conditional likelihood.

We adapt the least absolute shrinkage and selection operator (lasso) and other sparse methods (elastic net and bootstrapped versions of lasso) to the conditional logistic regression model and provide a full R implementation. These variable selection procedures are applied in the context of case-crossover studies. We study the performances of conventional and sparse modelling strategies by simulations, then empirically compare results of these methods on the analysis of the association between exposure to medicinal drugs and the risk of causing an injurious road traffic crash in elderly drivers. Controlling the false discovery rate of lasso-type methods is still problematic, but this problem is also present in conventional methods. The sparse methods have the ability to provide a global analysis of dependencies, and we conclude that some of the variants compared here are valuable tools in the context of case-crossover studies with a large number of variables.

A web-based prospective cohort study of home, leisure, school and sports injuries in France: a descriptive analysis.

BACKGROUND: Home and leisure injuries (HLIs) are a major public health problem. Cohort studies among general population are needed for targeted preventive actions but remain scarce. We quantify and qualify the HLIs collected prospectively in the MAVIE (Mutualists against Home and Leisure Injuries) observatory, a web-based cohort among volunteers of the French general population. METHODS: Participants reported HLIs from November 2014 to December 2019. We calculated crude and standardized incidence rates (SIRs) on the entire cohort, for each of the selected socio-demographic variables and each of the injury circumstances (place and activity), mechanisms, and injury severity levels. We also described other HLIs characteristics and consequences. RESULTS: Out of the 29,931 household members enrolled in the cohort, 12,419 participants completed the questionnaires. Among them, 8640 participants provided follow-up data, leading to a follow-up of 6302 persons for 5.2 years and 2483 HLIs were reported. We obtained a SIR of 85.0 HLIs per 1000 persons-years. Most reported injuries did not require emergency department attendance or hospitalization (64%). SIRs were higher in children (< 15 years of age) (109.1 HLIs per 1000 persons-years; 95% CI, 78.2-140.1) and adults aged 70 years and older (123.7 HLIs per 1000 persons-years; 95% CI, 79.2-168.3). Struck or hit by fall was the most frequent injury mechanism (52%) and also among the most severe injuries (73% of Struck or hit by fall HLIs ending with hospitalization). Sport (without contact with nature), and leisure and play activities were the injury circumstances with higher SIRs, 15.2 HLIs per 1000 persons-years (95% CI, 14.6-15.8) and 11.2 HLIs per 1000 persons-years (95% CI, 10.7-11.6), respectively. Outdoor sport activity (in contact with nature) was the circumstance with the highest proportion of hospitalizations (18% of outdoor sports HLIs ending with hospitalization). CONCLUSION: The incidences, causes, and consequences of HLI differ by age group and are mainly related to the performance of certain activities. Although the participants in the MAVIE cohort were not representative of the French population. Our study identified potential sub-populations and specific types of HLIs that should be targeted by future studies concerning risk factors and prevention programs.

Cohort profile: MAVIE a web-based prospective cohort study of home, leisure, and sports injuries in France.

MAVIE is a web-based prospective cohort study of Home, Leisure, and Sports Injuries with a longitudinal follow-up of French general population volunteers. MAVIE participants are voluntary members of French households, including overseas territories. Participation in the cohort involves answering individual and household questionnaires and relevant exposures and prospectively reporting injury events during the follow-up. Recruitment and data collection have been in progress since 2014. The number of participants as of the end of the year 2019 was 12,419 from 9,483 households. A total of 8,640 participants provided data during follow-up. Respondents to follow-up were composed of 763 children aged 0-14, 655 teenagers and young adults aged 15-29, 6,845 adults, and 377 people aged 75 or more. At the end of the year 2019, 1,698 participants had reported 2,483 injury events. Children, people aged 50 and more, people with poor self-perceived physical and mental health, people who engage in sports activities, and people with a history of injury during the year before recruitment were more likely to report new injuries. An interactive mobile/web application (MAVIE-Lab) was developed to help volunteers decide on personalized measures to prevent their risks of HLIs. The available data provides an opportunity to analyse multiple exposures at both the individual and household levels that may be associated with an increased risk of trauma. The ongoing analysis includes HLI incidence estimates, the determination of health-related risk factors, a specific study on the risk of home injury, another on sports injuries, and an analysis of the role of cognitive skills and mind wandering. Volunteers form a community that constitutes a population laboratory for preventative initiatives.

Prescription medicines and the risk of road traffic crashes: a French registry-based study.

BACKGROUND: In recent decades, increased attention has been focused on the impact of disabilities and medicinal drug use on road safety. The aim of our study was to investigate the association between prescription medicines and the risk of road traffic crashes, and estimate the attributable fraction. METHODS AND FINDINGS: We extracted and matched data from three French nationwide databases: the national health care insurance database, police reports, and the national police database of injurious crashes. Drivers identified by their national health care number involved in an injurious crash in France, between July 2005 and May 2008, were included in the study. Medicines were grouped according to the four risk levels of the French classification system (from 0 [no risk] to 3 [high risk]). We included 72,685 drivers involved in injurious crashes. Users of level 2 (odds ratio [OR]  = 1.31 [1.24-1.40]) and level 3 (OR  = 1.25 [1.12-1.40]) prescription medicines were at higher risk of being responsible for a crash. The association remained after adjustment for the presence of a long-term chronic disease. The fraction of road traffic crashes attributable to levels 2 and 3 medications was 3.3% [2.7%-3.9%]. A within-person case-crossover analysis showed that drivers were more likely to be exposed to level 3 medications on the crash day than on a control day, 30 days earlier (OR  = 1.15 [1.05-1.27]). CONCLUSION: The use of prescription medicines is associated with a substantial number of road traffic crashes in France. In light of the results, warning messages appear to be relevant for level 2 and 3 medications and questionable for level 1 medications. A follow-up study is needed to evaluate the impact of the warning labeling system on road traffic crash prevention.

The impact of medicinal drugs on traffic safety: a systematic review of epidemiological studies.

PURPOSE: To evaluate the quality of epidemiological research into effects of medicinal drugs on traffic safety and the current knowledge in this area. DATA SOURCES: 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. CONCLUSION: There is a need for large studies, investigating the role of individual substances in the risk of road traffic crashes.

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.

Road safety and distraction, results from a responsibility case-control study among a sample of road users interviewed at the emergency room.

Despite the complexities of the driving task, more and more drivers engage in non-driving secondary tasks that take their hands (manual distraction), their eyes (visual distraction) and/or their mind (cognitive distraction) away from their primary task. Inattention arising from external distractions has received much less consideration beyond the impact of mobile phone use. We aimed to investigate the association between distraction behind the wheel and risk of being responsible for a road traffic crash in a responsibility case-control study. The study population included 1912 drivers injured in a road traffic crash recruited in two rounds of recruitment (from April 2010 to August 2011 and from March 2013 to January 2015) in the adult emergency department of Bordeaux University Hospital (France). Responsibility levels were estimated using a standardized method. Self-reported activities among a pre-established list of potential distractions were combined into four external distraction variables: visual distraction, manual distraction, auditory distraction, and verbal interaction. A significantly increased risk of being responsible for a road traffic crash was associated with the exposure to activities that take drivers' eyes off the road (adjusted odds ratio 2.99, 95% confidence interval 1.42-6.28) and activities that take drivers' hands off the wheel (adjusted odds ratio 2.12, 95% confidence interval 1.20-3.75). No significant associations were found for verbal interaction and listening to the radio and/or singing. This study suggests that beyond the use of mobile phone, particular attention must be paid to activities that involve visual and/or manual distraction.

Road traffic crash risk associated with prescription of hydroxyzine and other sedating H1-antihistamines: A responsibility and case-crossover study.

BACKGROUND: H1 antihistamines differ from each other by their ability to cross the blood-brain barrier. The resulting sedating effect can be sought in therapy but may be a driving hazard. The aim of this study was to estimate the impact of sedating H1-antihistamines on the risk of road traffic crash, with a particular focus on hydroxyzine which is also indicated as an anxiolytic in France. METHODS: The study consisted in extracting and matching data from three French nationwide databases: the national healthcare insurance database, police reports and the police national database of injurious crashes. All sedating H1-antihistamines, including hydroxyzine, were considered in the study. A case-control analysis, in which responsible drivers were cases and non-responsible were controls was performed. A case-crossover analysis, comparing for the same subject exposure during a period immediately before the crash with exposure during an earlier period, was also conducted. RESULTS: The extraction and matching procedures over the July 2005-December 2011 period led to the inclusion of 142,771 drivers involved in an injurious road traffic crash. The responsibility study found an increased risk of being responsible for an injurious road traffic crash in hydroxyzine users who were registered with a long-term chronic disease (mostly psychiatric disorders) on the day of the crash (OR=1.67 [1.22-2.30]). Among them, the risk was even higher in drivers with highest exposure levels (OR=2.60 [1.23-5.50]). There was no impact of sedating H1 antihistamine treatment initiation on the risk of crash. CONCLUSION: Even if it is difficult to disentangle the part of the increased risk that would be causally related to hydroxyzine and the part related to behaviours of patients with a heavy psychiatric disorder, our study raises the alarm on the crash risk linked to hydroxyzine utilization in countries in which the anxiolytic indication is widespread.

The distracted mind on the wheel: Overall propensity to mind wandering is associated with road crash responsibility.

The role of distractions on attentional lapses that place road users in higher risk of crash remains poorly understood. We aimed to assess the respective impact of (i) mind wandering trait (propensity to mind wander in the everyday life as measured with a set of 4 questions on the proportion of time spent mind wandering in 4 different situations) and (ii) mind wandering state (disturbing thoughts just before the crash) on road crash risk using a comparison between responsible and non-responsible drivers. 954 drivers injured in a road crash were interviewed at the adult emergency department of the Bordeaux university hospital in France (2013-2015). Responsibility for the crash, mind wandering (trait/state), external distraction, alcohol use, psychotropic drug use, and sleep deprivation were evaluated. Based on questionnaire reports, 39% of respondents were classified with a mind wandering trait and 13% reported a disturbing thought just before the crash. While strongly correlated, mind wandering state and trait were independently associated with responsibility for a traffic crash (State: OR = 2.51, 95% CI: 1.64-3.83 and Trait: OR = 1.62, 95% CI: 1.22-2.16 respectively). Self-report of distracting thoughts therefore did not capture the entire risk associated with the propensity of the mind to wander, either because of under-reported thoughts and/or other deleterious mechanisms to be further explored.

The increased risk of road crashes in attention deficit hyperactivity disorder (ADHD) adult drivers: driven by distraction? Results from a responsibility case-control study.

BACKGROUND AND OBJECTIVE: Both distractions (external and internal) and attention-deficit/hyperactivity disorder (ADHD) are serious risk factors for traffic crashes and injuries. However, it is still unknown if ADHD (a chronic condition) modifies the effect of distractions (irregular hazards) on traffic crashes. The objective of this study was to assess the effects of distractions and ADHD on traffic crash responsibility. METHODS: A responsibility case-control study was conducted in the adult emergency department of Bordeaux University Hospital, France. Subjects were recruited among drivers injured in a motor vehicle crash between April 2010 and August 2011. Responsibility levels were estimated using a standardized method. Frequencies of exposures were compared between drivers responsible and drivers not responsible for the crash. Independent risk factors were identified using a multivariate logistic regression including test interactions between distractions and ADHD. RESULTS: A total of 777 subjects were included in the analysis. Factors associated with responsibility were distraction induced by an external event (adjusted OR (aOR) = 1.47; 95% confidence interval (CI) [1.06-2.05]), distraction induced by an internal thought (aOR = 2.38; CI: [1.50-3.77]) and ADHD (aOR = 2.18 CI: [1.22-3.88]). The combined effect of ADHD and external distractions was strongly associated with responsibility for the crash (aOR = 5.79 CI: [2.06-16.32]). Interaction assessment showed that the attributable proportion due to the interaction among participants with both exposures was 68%. DISCUSSION: Adults with ADHD are a population at higher risk of being responsible for a road traffic crash when exposed to external distractions. This result reinforces the need to diagnose adult ADHD and to include road safety awareness messages delivered by the physician. Developing advanced driver assistance systems devoted to the management of attention lapses is also increasingly relevant for these drivers.

Long-term chronic diseases and crash responsibility: a record linkage study.

OBJECTIVE: To assess the population impact of chronic conditions on the risk of road traffic crashes. 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. Exposure to chronic conditions were compared between responsible and nonresponsible drivers. Analysis was performed using the Lasso (least absolute shrinkage and selection operator) method. RESULTS: 69,630 drivers involved in an injurious crash in France between 2005 and 2008, were included. 6210 (8.9%) were suffering from at least one long-term disease. When adjusted for prescription of medicines, blood alcohol, demographic driver characteristics and crash characteristics, increased risk of being responsible for a crash was found in drivers registered in the French healthcare database with the following long-term diseases: epilepsy (odds ratio [OR]=2.53 [1.53-4.20]), type 1 diabetes (OR=1.47) [1.12-1.92], alcoholic liver disease (OR=3.37 [1.40-8.13]), asthma (OR=1.72 [1.13-2.60]) and specific personality disorders (OR=1.35 [1.05-1.74]). No association was found for cardiovascular diseases or Alzheimer's disease. CONCLUSION: The results update the list of medical conditions that may impair driving skills. However, results should be considered cautiously with regards to potential regulatory driving judgments that could have a negative impact on patients' social life.