Schizophrenia, antipsychotic treatment adherence and driver responsibility for motor vehicle crash: a population-based retrospective study in British Columbia, Canada.

OBJECTIVE: To examine the relationship between schizophrenia, antipsychotic medication adherence and driver responsibility for motor vehicle crash. DESIGN: Retrospective observational cohort study using 20 years of population-based administrative health and driving data. SETTING: British Columbia, Canada. PARTICIPANTS: Licensed drivers who were involved in a police-attended motor vehicle crash in British Columbia over a 17-year study interval (2000-16). EXPOSURES: Incident schizophrenia was identified using hospitalisation and physician services data. Antipsychotic adherence was estimated using prescription fill data to calculate the 'medication possession ratio' (MPR) in the 30 days prior to crash. PRIMARY OUTCOME MEASURES: We deemed drivers 'responsible' or 'non-responsible' for their crash by applying a validated scoring tool to police-reported crash data. We used logistic regression to evaluate the association between crash responsibility and exposures of interest. RESULTS: Our cohort included 808 432 drivers involved in a police-attended crash and for whom crash responsibility could be established. In total, 1689 of the 2551 drivers with schizophrenia and 432 430 of the 805 881 drivers without schizophrenia were deemed responsible for their crash, corresponding to a significant association between schizophrenia and crash responsibility (66.2% vs 53.7%; adjusted OR (aOR), 1.67; 95% CI, 1.53 to 1.82; p<0.001). The magnitude of this association was modest relative to established crash risk factors (eg, learner license, age ≥65 years, impairment at time of crash). Among the 1833 drivers with schizophrenia, near-optimal antipsychotic adherence (MPR ≥0.8) in the 30 days prior to crash was not associated with lower crash responsibility (aOR, 1.04; 95% CI, 0.83 to 1.30; p=0.55). CONCLUSIONS: Crash-involved drivers with schizophrenia are more likely to be responsible for their crash, but the magnitude of risk is similar to socially acceptable risk factors such as older age or possession of a learner license. Contemporary driving restrictions for individuals with schizophrenia appear to adequately mitigate road risks, suggesting more stringent driving restrictions are not warranted.

Trajectories of health-related quality of life following road trauma: Latent growth mixture modeling across a 12-month cohort study.

INTRODUCTION: Health-related quality of life (HRQoL) should be considered when evaluating the burden of road trauma (RT) injuries. This study aimed to identify distinct HRQoL trajectories following minor to severe RT injury and determine characteristics of trajectory membership. METHODS: This prospective inception cohort study recruited 1480 RT survivors from three emergency departments in British Columbia, Canada (July 2018 - March 2020). HRQoL outcome was measured with the Short Form 12 survey (SF-12) and the 5-level version of the EuroQol instrument (EQ-5D-5L) at baseline (pre-injury) and at 2, 4, 6, and 12 months post-injury. Potential predictors of outcome trajectory included sociodemographic, psychological, medical, crash, and injury factors collected at baseline. We used a latent growth mixture model to identify distinct recovery trajectories and multinomial logistic regression to determine predictors of trajectory membership. RESULTS: Three distinct HRQoL trajectories were identified for SF-12 subscales and EQ-5D-5L measures: Low/Moderate-Stable, High-Large decline, and High-Slight decline. Participants in the Low/Moderate-Stable trajectory had persistent low to moderate HRQoL before and after the injury. Those in the High-Large decline trajectory had good pre-injury HRQoL followed by persistently decreased HRQoL afterwards. The High-Slight decline trajectory was characterized by good pre-injury HRQoL and only a slight decline afterwards. Participants in the Low/Moderate-Stable and High-Large decline trajectories were considered at risk of permanently poor HRQoL following RT injury given their low HRQoL over a long period of time. Characteristics that placed participants in the Low/Moderate-Stable trajectory were older age, female gender, poor pre-injury health (medical comorbidity, prescribed medication use, complaints in the injured body area(s)), pre-injury somatic symptoms, pain catastrophizing or psychological distress, injury severity (ISS) and injury pain. Patients with head injury were less likely to be in the Low/Moderate-Stable trajectory. Risk factors for membership in the High-Large decline trajectory included older age (for physical HRQoL), younger age (for mental HRQoL), female gender, living alone, pre-injury psychological distress, ISS, injury pain, no expectations for a fast recovery, as well as head injuries, spine/back injuries or lower extremity injuries. CONCLUSIONS: This study highlighted the heterogeneity of HRQoL trajectories following RT injury and the importance of considering differences between characteristics of survivors. In addition to injury type and severity, outcome is related to demographic factors, pre-injury health and pre-injury psychological factors.

Twelve-month recovery following road trauma: Results from an inception cohort in Vancouver, Canada.

BACKGROUND: Injury-related disability following road trauma is a major public health concern. Unfortunately, outcome following road trauma and risk factors for poor recovery are inadequately studied, especially for road trauma survivors with minor injuries that do not require hospitalization. OBJECTIVES: This manuscript reports 12-month recovery outcomes for a large cohort of road trauma survivors. METHODS: This was a prospective, observational inception cohort study of 1,480 road trauma survivors recruited between July 2018 and March 2020 from 3 trauma centres in British Columbia, Canada. Participants were aged ≥16 years and arrived in a participating emergency department within 24 h of a motor vehicle collision. Data on baseline health and injury severity were collected from structured interviews and medical records. Outcome measures, including the SF-12, were collected during follow-up interviews at 2, 4, 6 and 12 months. Predictors of recovery outcomes were identified using Cox proportional hazards models and summarized using hazard ratios. RESULTS: Only 42 % of participants self-reported full recovery and only 66 % reported a return to usual daily activities. Females, older individuals, pedestrians, and those who required hospital admission had a poorer recovery than other groups. Similar patterns were observed for the SF-12 physical component. For the SF-12 mental component, no significant differences were observed between participants admitted to hospital and those discharged home from the ED. Return to work was reported by 77 % of participants who had a paying job at baseline, with no significant differences between sex and age groups. CONCLUSIONS: In a large cohort of road trauma survivors, under half self-reported full recovery one year after the injury. Poor mental health recovery was observed in both participants admitted to hospital and those discharged home from the ED. This finding may indicate a need for early intervention and continued mental health monitoring for all injured individuals, including for those with less serious injuries.

Health-related quality of life in the year following road trauma: Longitudinal analysis using piecewise latent curve modeling.

BACKGROUND: Road trauma (RT) survivors have reduced health-related quality of life (HRQoL). We identified phases and predictors of HRQoL change following RT injury. METHODS: In a prospective cohort study of 1480 Canadian RT survivors aged 16 to 103 years (July 2018 - March 2020), physical component (PCS) and mental component (MCS) summary scores from the SF-12v2 were measured pre-injury and 2, 4, 6, and 12 months post-injury and their trajectories were analyzed with piecewise latent growth curve modeling. Potential predictors of HRQoL changes included sociodemographic, psychological, medical, and trauma-related factors. RESULTS: PCS and MCS scores worsened from pre-injury to 2-months (phase 1) and then improved (phase 2), but never regained baseline values. Older age, somatic symptoms and pain catastrophizing were associated with lower preinjury PCS and MCS scores. Psychological distress was associated with lower preinjury MCS scores and higher preinjury PCS scores. Phase 1 PCS scores decreased most in females, participants with fewer pre-injury somatic symptoms and those without expectations for fast recovery. Phase 1 MCS decreases were associated with younger age, female sex, living alone, lower psychological distress, lack of expectation for fast recovery and higher injury pain. In phase 2, MCS improved most in participants not using recreational drugs; PCS improved most in participants with higher education and longer recovery expectations. LIMITATIONS: There may be recall bias with reporting pre-injury HRQoL. Selection bias is possible. CONCLUSIONS: Many factors influence HRQoL following RT. These findings may inform measures to minimize HRQoL reduction following RT and speed up subsequent recovery.

Off-road vehicle crashes: dangers of alcohol and drug impairment.

BACKGROUND: Impaired driving is a public health issue, yet little is known concerning the prevalence of substance use in drivers involved in off-road vehicle crashes. The goal of the present study was to describe the demographics and prevalence of alcohol and drug use in drivers of off-road vehicle crashes. METHODS: In this observational substudy, we collected clinical and toxicological data on all moderately or severely injured off-road vehicle drivers who had blood samples obtained within 6 h of the crash. Clinical data were extracted from patients' medical charts and toxicology analyses were performed for blood alcohol, cannabinoids, recreational drugs, and impairing medications. RESULTS: Thirty-three injured drivers met the inclusion criteria. The mean age was 37.6 ± 13.4 years and 79% were male. Blood alcohol was detected in 58% of drivers and 42% of these were above the legal limit. Tetrahydrocannabinol was positive in 12% of drivers, and 18% were positive for recreational drugs. Opiates were detected in 21% of drivers. Overall, 85% were positive for at least one substance and 39% tested positive for multiple substances. CONCLUSION: This study presents the first evidence of alcohol and drug use in off-road vehicle drivers after cannabis legalization in Canada. Our results show that over half of drivers in off-road vehicle crashes test positive for alcohol and 30% tested positive for THC, cocaine, or amphetamines. Opiates are also commonly detected in off-road vehicle drivers. Emergency department (ED) visits resulting from drug driving of off-road vehicles serve as an opportunity for screening, initiating treatment, and connecting patients to interventions for substance use disorders.

ABSTRAIT: CONTEXTE: La conduite avec facultés affaiblies est un problème de santé publique, mais on sait peu de choses sur la prévalence de la toxicomanie chez les conducteurs impliqués dans des accidents de la route. L'objectif de la présente étude était de décrire la démographie et la prévalence de la consommation d'alcool et de drogues chez les conducteurs de véhicules hors route. MéTHODES: Dans le cadre de cette sous-étude observationnelle, nous avons recueilli des données cliniques et toxicologiques sur tous les conducteurs de véhicules hors route ayant subi des blessures modérées ou graves qui avaient reçu des échantillons de sang dans les 6 heures suivant l'accident. Les données cliniques ont été extraites des dossiers médicaux des patients et des analyses toxicologiques ont été effectuées pour l'alcool dans le sang, les cannabinoïdes, les drogues récréatives et les médicaments pour les facultés affaiblies. RéSULTATS: Trente-trois conducteurs blessés répondaient aux critères d'inclusion. L'âge moyen était de 37,6 13,4 ans et 79 % étaient des hommes. L'alcool dans le sang a été détecté chez 58 % des conducteurs et 42 % d'entre eux dépassaient la limite légale. Le tétrahydrocannabinol était positif chez 12 % des conducteurs et 18 % étaient positifs aux drogues récréatives. Des opiacés ont été détectés chez 21 % des conducteurs. Dans l'ensemble, 85 % étaient positifs pour au moins une substance et 39 % étaient positifs pour plusieurs substances. CONCLUSION: Cette étude présente les premières preuves de la consommation d'alcool et de drogues chez les conducteurs de véhicules hors route après la légalisation du cannabis au Canada. Nos résultats montrent que plus de la moitié des conducteurs de véhicules hors route ont un résultat positif au test de dépistage de l'alcool et 30 % ont un résultat positif au test de dépistage du THC, de la cocaïne ou des amphétamines. Les opiacés sont également couramment détectés chez les conducteurs de véhicules hors route. Les visites aux services d'urgence (SU) découlant de la conduite de véhicules hors route avec facultés affaiblies par la drogue constituent une occasion de dépistage, d'amorcer un traitement et de mettre les patients en contact avec des interventions pour les troubles liés à la consommation de substances.

Syncope While Driving and the Risk of a Subsequent Motor Vehicle Crash.

STUDY OBJECTIVE: Syncope that occurs while driving can result in a motor vehicle crash. Whether individuals with a prior syncope-related crash exhibit an exceptional risk of subsequent crash remains uncertain. METHODS: We performed a population-based retrospective observational study of patients diagnosed with 'syncope and collapse' at any of 6 emergency departments in British Columbia, Canada (2010 to 2015). Data were obtained from chart abstraction, administrative health records, insurance claims and police crash reports. We compared crash-free survival among individuals with crash-associated syncope (a crash and an emergency visit for syncope on the same date) to that among controls with syncope alone (no crash on date of emergency visit for syncope). RESULTS: In the year following their index emergency visit, 13 of 63 drivers with crash-associated syncope and 852 of 9,160 controls with syncope alone experienced a subsequent crash as a driver (crash risk 21% versus 9%). After accounting for censoring and potential confounders, crash-associated syncope was not associated with a significant increase in the risk of subsequent crash (adjusted hazard ratio [aHR] 1.38, 95% confidence interval [CI] 0.78 to 2.47). Individuals with crash-associated syncope were 31-fold more likely to have physician driving advice documented during their index visit (prevalence ratio 31.0, 95% CI, 21.3 to 45.1). In the subgroup without documented driving advice, crash-associated syncope was associated with a significant increase in subsequent crash risk (aHR 1.88, 95% CI 1.06 to 3.36). CONCLUSIONS: Crash risk after crash-associated syncope appears similar to crash risk after syncope alone.

Syncope and Traffic Crash: A Population-Based Case-Crossover Analysis.

BACKGROUND: Among individuals with recent syncope, recurrence of syncope while driving might incapacitate a driver and cause a motor vehicle crash. Current driving restrictions assume that some forms of syncope transiently increase crash risk. We evaluated whether syncope is associated with a transient increase in crash risk. METHODS: We performed a case-crossover analysis of linked administrative health and driving data from British Columbia, Canada (2010 to 2015). We included licensed drivers who visited an emergency department with "syncope and collapse" and who were involved as a driver in an eligible motor vehicle crash, both within the study interval. Using conditional logistic regression, we compared the rate of emergency visits for syncope in the 28 days before crash (the "pre-crash interval") with the rate of emergency visits for syncope in 3 self-matched 28-day control intervals (ending 6, 12, and 18 months before the crash). RESULTS: Among eligible crash-involved drivers, 47 of 3026 pre-crash intervals and 112 of 9078 control intervals had emergency visits for syncope, indicating syncope was not significantly associated with subsequent crash (1.6% vs 1.2%; adjusted odds ratio [OR], 1.27; 95% confidence interval [CI], 0.90-1.79; P = 0.18). There was no significant association between syncope and crash in subgroups at higher risk for adverse outcomes after syncope (eg, age > 65 years, cardiovascular disease, cardiac syncope). CONCLUSIONS: In the context of prevailing modifications of driving behaviour after syncope, an emergency department visit for syncope did not transiently increase the risk of subsequent traffic collision. Overall crash risks after syncope appear to be adequately addressed by current driving restrictions.

Circumstances and outcome of active transportation injuries: protocol of a British Columbian inception cohort study.

INTRODUCTION: Active transport (AT) is promoted by urban planners and health officials for its environmental, economic and societal benefits and its uptake is increasing. Unfortunately, AT users can be injured or killed due to falls or collisions. Active transport injury (ATI) prevention efforts are hindered by limited research on the circumstances, associated infrastructure, injury pattern, severity and outcome of ATI events. This study seeks to address these knowledge gaps by identifying built environment features associated with injury and risk factors for a poor outcome following ATI. METHODS AND ANALYSIS: This prospective observational study will recruit an inception cohort of 2000 ATI survivors, including pedestrians, cyclists and micromobility users aged 16 years and older who arrive at a participating emergency department within 48 hours of sustaining an ATI. Baseline interviews capture demographic and socioeconomic information, pre-injury health and functional status, as well as circumstances of the injury event and recovery expectations. Follow-up interviews at 2, 4, 6 and 12 months postinjury (key stages of recovery) use standardised health-related quality of life tools to determine physical and mental health outcomes, functional recovery and healthcare resource use and lost productivity costs. ETHICS AND DISSEMINATION: The Active Transportation Injury Circumstances and Outcome Study is approved by our institutional research ethics board and the research ethics boards of all participating sites. This study aims to provide healthcare providers with knowledge of risk factors for poor outcome following ATI with the goal of improving patient management. Additionally, this study will provide insight into the circumstances of ATI events including built environment features and how those circumstances relate to recovery outcomes. This information can be used to inform city engineers and planners, policymakers and public health officials to plan roadway design and injury prevention policy.

Did implementation of no-fault auto-insurance in British Columbia, Canada, impact return to work following road trauma? Protocol for a before-after survival analysis.

INTRODUCTION: Road trauma (RT) is a major public health problem that often results in prolonged absenteeism from work. Limited evidence suggests that recovery after RT is associated with automobile insurance compensation schemes. In May 2021, British Columbia, Canada switched from fault-based to no-fault auto-insurance coverage. This manuscript presents the protocol for a planned evaluation of that natural experiment: We will evaluate the impact of changing automobile insurance schemes on return to work following RT. METHODS AND ANALYSIS: The evaluation will use a before-after design to analyse auto-insurance claims (1 April 2019 to 30 April 2024) in order to compare recovery of claimants with non-catastrophic injuries who filed claims under the no-fault insurance scheme to that of those who filed claims under the previous system. Claimants will be followed from date of injury until they return to work or have been followed for 6 months (right-censored). We will perform sensitivity analyses to examine the robustness of our findings. First, we will exclude injuries that occurred during the COVID-19 provincial State of Emergency. Second, we will use propensity score methods rather than conventional covariate adjustment to address potential imbalance between characteristics of claimants pre-change and post-change. Finally, as the implementation effect may have a heterogeneous association with time off work, we will use quantile regression with right-censoring at 6 months to model differences in return to work at the 25th, 50th, 75th and 90th percentiles. ETHICS AND DISSEMINATION: The study uses de-identified data and is approved by the University of British Columbia Clinical Research Ethics Board (H20-03644). This research is funded by the Insurance Corporation of British Columbia (ICBC). Findings will be published in the peer-reviewed literature and summarised in a report prepared for ICBC. We anticipate that our findings will inform policy decisions in other jurisdictions considering switching to no-fault auto-insurance schemes.

Demographic and clinical profile of an inception cohort of road trauma survivors.

BACKGROUND: Road trauma is a major public health concern, often resulting in reduced health-related quality of life and prolonged absenteeism from work even after so-called 'minor' injuries that do not result in hospitalization. This manuscript compares pre-injury health, sociodemographic characteristics and injury details between age, sex, and road user categories in a cohort of 1,480 road trauma survivors. METHODS: This was a prospective observational inception cohort study of road trauma survivors recruited between July 2018 and March 2020 from three trauma centres in British Columbia, Canada. Participants were aged ≥ 16 years and arrived in a participating emergency department within 24 h of involvement in a motor vehicle collision. Data were collected from structured interviews and review of medical records. RESULTS: The cohort of 1,480 road trauma survivors included 280 pedestrians, 174 cyclists, 118 motorcyclists, 683 motor vehicle drivers, and 225 passengers. Median age was 40 (IQR = [27, 57]) years; 680 (46%) were female. Males and younger patients were significantly more likely to report better pre-injury physical health. Motorcyclists and cyclists tended to report better physical health and less severe somatic symptoms, whereas pedestrians and motor vehicle drivers reported better mental health. Injury severity and hospital admission rates were higher in pedestrians and motorcyclists and lower in motorists. Upper and lower extremity injuries were most common in pedestrians, cyclists and motorcyclists, whereas neck injuries were most common in motor vehicle drivers and passengers. CONCLUSIONS: In a large cohort of road trauma survivors, overall injury severity was low. Motorcyclists and pedestrians, but not cyclists, had more severe injuries than motorists. Extremity injuries were more common in vulnerable road users. Future research will investigate one-year recovery outcomes and identify risk factors for poor recovery.

Syncope and subsequent traffic crash: A responsibility analysis.

BACKGROUND: Physicians are often asked to counsel patients about driving safety after syncope, yet little empirical data guides such advice. METHODS: We identified a population-based retrospective cohort of 9,507 individuals with a driver license who were discharged from any of six urban emergency departments (EDs) with a diagnosis of 'syncope and collapse'. We examined all police-reported crashes that involved a cohort member as a driver and occurred between 1 January 2010 and 31 December 2016. We categorized crash-involved drivers as 'responsible' or 'non-responsible' for their crash using detailed police-reported crash data and a validated responsibility scoring tool. We then used logistic regression to test the hypothesis that recent syncope was associated with driver responsibility for crash. RESULTS: Over the 7-year study interval, cohort members were involved in 475 police-reported crashes: 210 drivers were deemed responsible and 133 drivers were deemed non-responsible for their crash; the 132 drivers deemed to have indeterminate responsibility were excluded from further analysis. An ED visit for syncope occurred in the three months leading up to crash in 11 crash-responsible drivers and in 5 crash-non-responsible drivers, suggesting that recent syncope was not associated with driver responsibility for crash (adjusted odds ratio, 1.31; 95%CI, 0.40-4.74; p = 0.67). However, all drivers with cardiac syncope were deemed responsible, precluding calculation of an odds ratio for this important subgroup. CONCLUSIONS: Recent syncope was not significantly associated with driver responsibility for traffic crash. Clinicians and policymakers should consider these results when making fitness-to-drive recommendations after syncope.

Syncope and the Risk of Subsequent Motor Vehicle Crash: A Population-Based Retrospective Cohort Study.

Importance: Medical driving restrictions are burdensome, yet syncope recurrence while driving can cause a motor vehicle crash (MVC). Few empirical data inform current driving restrictions after syncope. Objective: To examine MVC risk among patients visiting the emergency department (ED) after first-episode syncope. Design, Setting, and Participants: A population-based, retrospective observational cohort study of MVC risk after first-episode syncope was performed in British Columbia, Canada. Patients visiting any of 6 urban EDs for syncope and collapse were age- and sex-matched to 4 control patients visiting the same ED in the same month for a condition other than syncope. Patients' ED medical records were linked to administrative health records, driving history, and detailed crash reports. Crash-free survival among individuals with syncope was then compared with that among matched control patients. Data analyses were performed from May 2020 to March 2022. Exposures: Initial ED visit for syncope. Main Outcomes and Measures: Involvement as a driver in an MVC in the year following the index ED visit. Crashes were identified using insurance claim data and police crash reports. Results: The study cohort included 43 589 patients (9223 patients with syncope and 34 366 controls; median [IQR] age, 54 [35-72] years; 22 360 [51.3%] women; 5033 [11.5%] rural residents). At baseline, crude MVC incidence rates among both the syncope and control groups were higher than among the general population (12.2, 13.2, and 8.2 crashes per 100 driver-years, respectively). In the year following index ED visit, 846 first crashes occurred in the syncope group and 3457 first crashes occurred in the control group, indicating no significant difference in subsequent MVC risk (9.2% vs 10.1%; adjusted hazard ratio [aHR], 0.93; 95% CI, 0.87-1.01; P = .07). Subsequent crash risk among patients with syncope was not significantly increased in the first 30 days after index ED visit (aHR, 1.07; 95% CI, 0.84-1.36; P = .56) or among subgroups at higher risk of adverse events after syncope (eg, age >65 years; cardiogenic syncope; Canadian Syncope Risk Score ≥1). Conclusions and Relevance: The findings of this population-based retrospective cohort study suggest that patients visiting the ED with first-episode syncope exhibit a subsequent crash risk no different than the average ED patient. More stringent driving restrictions after syncope may not be warranted.

Cannabis Legalization and Detection of Tetrahydrocannabinol in Injured Drivers.

BACKGROUND: The effect of cannabis legalization in Canada (in October 2018) on the prevalence of injured drivers testing positive for tetrahydrocannabinol (THC) is unclear. METHODS: We studied drivers treated after a motor vehicle collision in four British Columbia trauma centers, with data from January 2013 through March 2020. We included moderately injured drivers (those whose condition warranted blood tests as part of clinical assessment) for whom excess blood remained after clinical testing was complete. Blood was analyzed at the provincial toxicology center. The primary outcomes were a THC level greater than 0, a THC level of at least 2 ng per milliliter (Canadian legal limit), and a THC level of at least 5 ng per milliliter. The secondary outcomes were a THC level of at least 2.5 ng per milliliter plus a blood alcohol level of at least 0.05%; a blood alcohol level greater than 0; and a blood alcohol level of at least 0.08%. We calculated the prevalence of all outcomes before and after legalization. We obtained adjusted prevalence ratios using log-binomial regression to model the association between substance prevalence and legalization after adjustment for relevant covariates. RESULTS: During the study period, 4339 drivers (3550 before legalization and 789 after legalization) met the inclusion criteria. Before legalization, a THC level greater than 0 was detected in 9.2% of drivers, a THC level of at least 2 ng per milliliter in 3.8%, and a THC level of at least 5 ng per milliliter in 1.1%. After legalization, the values were 17.9%, 8.6%, and 3.5%, respectively. After legalization, there was an increased prevalence of drivers with a THC level greater than 0 (adjusted prevalence ratio, 1.33; 95% confidence interval [CI], 1.05 to 1.68), a THC level of at least 2 ng per milliliter (adjusted prevalence ratio, 2.29; 95% CI, 1.52 to 3.45), and a THC level of at least 5 ng per milliliter (adjusted prevalence ratio, 2.05; 95% CI, 1.00 to 4.18). The largest increases in a THC level of at least 2 ng per milliliter were among drivers 50 years of age or older (adjusted prevalence ratio, 5.18; 95% CI, 2.49 to 10.78) and among male drivers (adjusted prevalence ratio, 2.44; 95% CI, 1.60 to 3.74). There were no significant changes in the prevalence of drivers testing positive for alcohol. CONCLUSIONS: After cannabis legalization, the prevalence of moderately injured drivers with a THC level of at least 2 ng per milliliter in participating British Columbia trauma centers more than doubled. The increase was largest among older drivers and male drivers. (Funded by the Canadian Institutes of Health Research.).

Neighborhood Socioeconomic Deprivation and Youth Assault Injuries in Vancouver, Canada.

OBJECTIVE: To examine the degree to which neighborhood socioeconomic deprivation influences the risk of youth assault injury. STUDY DESIGN: Population-based retrospective study of youth aged 10-24 years seeking emergency medical care between 2012 and 2019 at 14 hospitals in Vancouver, Canada. Neighborhood material and social deprivation were examined as independent predictors of assault injury, accounting for spatial autocorrelation and controlling for neighborhood drinking establishment density. RESULTS: Our data included 4166 assault injuries among 3817 youth. Male sex, substance use, and mental health disorders were common among victims of assault. Relative to the least deprived quintile of neighborhoods, assault injury risk was 2-fold higher in the most materially deprived quintile of neighborhoods (incidence rate ratio per quintile increase, 1.17; 95% CI 1.06-1.30; P < .05), and risk in the most socially deprived quintile was more than 3-fold greater than in the least deprived quintile (incidence rate ratio per quintile increase, 1.35; 95% CI 1.21-1.50; P < .001). Assault risk was 147-fold greater between 2 and 3 AM on Saturday relative to the safest hours of the week. CONCLUSIONS: Neighborhood socioeconomic deprivation substantially increases the risk of youth assault injury. Youth violence prevention efforts should target socioeconomically deprived neighborhoods.

Medications and risk of motor vehicle collision responsibility in British Columbia, Canada: a population-based case-control study.

BACKGROUND: Many medications impair driving skills yet their influence on collision risk remains uncertain. We aimed to systematically investigate the risk of collision responsibility associated with common classes of prescription medications. METHODS: In this population-based case-control study we analysed linked driving and health records in British Columbia, Canada from Jan 1, 1997, to Dec 31, 2016. The study cohort included all drivers involved in an incident collision (defined as first collision after 3 collision-free years) that resulted in a police report. We scored police collision reports and classified drivers as responsible for the collision (cases) or not responsible (controls); drivers with indeterminate scores were excluded. We used logistic regression to determine odds of collision responsibility in drivers with current prescriptions for medications of interest versus drivers without prescriptions. To explore whether risk of collision responsibility was related to medication effect or driver factors, we compared risk in current medication users versus past users. To study whether drivers developed tolerance to medication effects, we compared risk in new (first 30 days of a prescription) versus established users. FINDINGS: During the study period, 4 906 925 drivers had their driving licence linked to health records; of these drivers, 747 662 unique drivers were involved in 837 919 incident collisions between Jan 1, 2000, and Dec 31, 2016. 382 685 drivers responsible for the collision (cases) and 332 259 drivers not responsible (controls) were included in the final analysis; 122 975 drivers with indeterminate responsibility were excluded. We found increased risk of collision responsibility in drivers prescribed sedating antipsychotics (adjusted odds ratio [aOR] 1·35 [98·75% CI 1·25-1·46]), long-acting benzodiazepines (aOR 1·30 [1·22-1·38]), short-acting benzodiazepines (aOR 1·25 [1·20-1·31]), and high-potency opioids (aOR 1·24 [1·17-1·30]). Among medications used for medical indications, the highest risk was seen in drivers prescribed neurological medications: cholinergic drugs (aOR 1·83 [1·39-2·40]), anticholinergic agents for Parkinson's disease (aOR 1·45 [1·08-1·96]), dopaminergic agents (aOR 1·20 [1·04-1·38]), and anticonvulsants (aOR 1·20 [1·14-1·26]). People currently taking benzodiazepines, non-sedating antidepressants, high-potency opioids, and anticonvulsants had increased risk compared with past users, and we did not find increased risk in new compared with established users of these drugs. INTERPRETATION: Drivers prescribed benzodiazepines or high-potency opioids are at increased risk of being responsible for collisions and this risk does not decrease over time. Several other classes of medications are associated with increased risk, but this association might be independent of medication effect. These findings can guide medication warnings and prescription choices and inform public education campaigns targeting impaired driving. FUNDING: Canadian Institutes of Health Research.

The association between monthly social assistance disbursement days and emergency department visits for trauma, mental health, and substance use.

OBJECTIVE: Social assistance helps fulfill the basic needs of low-income individuals. In British Columbia, social assistance is issued on the third or fourth Wednesday of every month. However, this sudden influx of resources may have negative health consequences. We investigated social assistance timing and emergency department (ED) visits related to trauma, mental health, and substance use. METHODS: We conducted a retrospective multi-centre observational study using 12 years of regional ED data from Vancouver, British Columbia (2008-2020). Each cheque week (the week following social assistance disbursement) was matched to a single control week (2 weeks prior to cheque week). We compared the number of ED visits for trauma, mental health, and substance use during cheque weeks versus control weeks. RESULTS: There were 253,360 visits during all weeks of interest. Cheque week was associated with significantly more ED visits for mental health and substance-related presentations (RR 1.07, 95% CI 1.03-1.11, p = 0.0006). These visits increased significantly for both males and females and for adults aged 17-64 years. Mental health and substance-related visits increased on the day of cheque disbursement (Wednesday) and the 4 days following (Thursday-Sunday). Trauma-related ED visits were elevated on the day of cheque disbursement, but not during other days of the week. CONCLUSIONS: Social assistance disbursement is followed by an increase in mental health and substance-related ED presentations and may be associated with an increase in trauma presentations on the day of cheque disbursement. These findings support calls for clinical and policy-level changes and support to reduce cheque day-associated harm.

RéSUMé: OBJECTIF: L'aide sociale permet de répondre aux besoins fondamentaux des personnes à faible revenu. En Colombie-Britannique, l'aide sociale est versée le troisième ou le quatrième mercredi de chaque mois. Cependant, cet afflux soudain de ressources peut avoir des conséquences négatives sur la santé. Nous avons étudié le calendrier de l'aide sociale et les visites aux urgences liées aux traumatismes, à la santé mentale et à la toxicomanie. MéTHODES: Nous avons mené une étude d'observation rétrospective multicentrique en utilisant 12 années de données sur les urgences régionales de Vancouver, en Colombie-Britannique (2008-2020). Chaque semaine de chèque (la semaine suivant le versement de l'aide sociale) a été appariée à une seule semaine de contrôle (deux semaines avant la semaine de chèque). Nous avons comparé le nombre de visites aux urgences pour traumatisme, santé mentale et toxicomanie pendant les semaines de chèque et les semaines de contrôle. RéSULTATS: Il y a eu 253 360 visites pendant toutes les semaines d'intérêt. La semaine des chèques a été associée à un nombre significativement plus élevé de visites aux urgences pour des présentations liées à la santé mentale et à la toxicomanie (RR 1,07, IC 95 % 1,03-1,11, p = 0,0006). Ces visites ont augmenté considérablement chez les hommes et les femmes et chez les adultes de 17 à 64 ans. Les visites liées à la santé mentale et aux substances ont augmenté le jour du versement du chèque (mercredi) et les quatre jours suivants (jeudi ­ dimanche). Les visites aux urgences liées à un traumatisme étaient plus nombreuses le jour de la remise du chèque, mais pas les autres jours de la semaine. CONCLUSIONS: Le versement de l'aide sociale est suivi d'une augmentation des présentations aux urgences liées à la santé mentale et à la toxicomanie et peut être associé à une augmentation des présentations de traumatismes le jour du versement du chèque. Ces résultats appuient les appels à des changements et à un soutien au niveau clinique et politique afin de réduire les préjudices associés au jour du chèque.

Injury patterns and circumstances associated with electric scooter collisions: a scoping review.

BACKGROUND: Electric scooters are personal mobility devices that have risen in popularity worldwide since 2017. Emerging reports suggest that both riders and other road users, such as pedestrians and cyclists, have been injured in electric scooter-associated incidents. We undertook a scoping review of the current literature to evaluate the injury patterns and circumstances of electric scooter-associated injuries. METHODS: A scoping review of literature published from 2010 to 2020 was undertaken following accepted guidelines. Relevant articles were identified in Medline, Embase, SafetyLit and Transport Research International Documentation using terms related to electric scooters, injuries and incident circumstances. Supplemental searches were conducted to identify relevant grey literature (non-peer-reviewed reports). RESULTS: Twenty-eight peer-reviewed studies and nine grey literature records were included in the review. The current literature surrounding electric scooter-associated injuries mainly comprises retrospective case series reporting clinical variables. Factors relating to injury circumstances are inconsistently reported. Findings suggest that the head, upper extremities and lower extremities are particularly vulnerable in electric scooter falls or collisions, while injuries to the chest and abdomen are less common. Injury severity was inconsistently reported, but most reported injuries were minor. Low rates of helmet use among electric scooter users were noted in several studies. CONCLUSION: Electric scooters leave riders vulnerable to traumatic injuries of varying severity. Future work should prospectively collect standardised data that include information on the context of the injury event and key clinical variables. Research on interventions to prevent electric scooter injuries is also needed to address this growing area of concern.

Prescription opioid use among drivers in British Columbia, 1997-2016.

BACKGROUND: Opioids increase the risk of traffic crash by limiting coordination, slowing reflexes, impairing concentration and producing drowsiness. The epidemiology of prescription opioid use among drivers remains uncertain. We aimed to examine population-based trends and geographical variation in drivers' prescription opioid consumption. METHODS: We linked 20 years of province-wide driving records to comprehensive population-based prescription data for all drivers in British Columbia (Canada). We calculated age- and sex-standardised rates of prescription opioid consumption. We assessed temporal trends using segmented linear regression and examined regional variation in prescription opioid use using maps and graphical techniques. RESULTS: A total of 46 million opioid prescriptions were filled by 3.0 million licensed drivers between 1997 and 2016. In 2016 alone, 14.7% of all drivers filled at least one opioid prescription. Prescription opioid use increased from 238 morphine milligram equivalents per driver year (MMEs/DY) in 1997 to a peak of 834 MMEs/DY in 2011. Increases in MMEs/DY were greatest for higher potency and long-acting prescription opioids. The interquartile range of prescription opioid dispensation by geographical region increased from 97 (Q1=220, Q3=317) to 416 (Q1=591, Q3=1007) MMEs/DY over the study interval. IMPLICATIONS: Patterns of prescription opioid consumption among drivers demonstrate substantial temporal and geographical variation, suggesting they may be modified by clinical and policy interventions. Interventions to curtail use of potentially impairing prescription medications might prevent impaired driving.