The relation between the use of psychoactive substances and the severity of the injury in a group of crash-involved drivers admitted to a regional trauma center

Cannabis, Impaired Driving, and Road Safety: An Overview of Key Questions and Issues

The road safety impact of cannabis has been a topic of much discussion and debate over the years. These discussions have been revitalized in recent years by initiatives in several jurisdictions to legalize non-medical cannabis. Canada became the second country to legalize non-medical cannabis use in October, 2018, preceded by Uruguay in December 2013. Road safety concerns were key issues in the Canadian government's deliberations on the issue. In this paper, we identify several key questions related to the impact of cannabis on road safety, and provide a consideration of the relevant literature on these questions. These questions cover several perspectives. From an epidemiological perspective, perhaps the central question is whether cannabis use contributes to the chances of being involved in a collision. The answer to this question has evolved in recent years as the ability to conduct the relevant studies has evolved. A related question is the extent to which cannabis plays an important role in road safety, and recent research has made progress in estimating the collisions, injuries, and deaths that may be attributed to cannabis use. Several questions relate to the behavioral and pharmacological effects of cannabis. One central question is whether cannabis affects driving skills in ways that can increase the chances of being involved in a collision. Another important question is whether the effects of the drug on the driving behavior of medical users is similar to, or different from, the effects on non-medical users and whether there are sex differences in the pharmacological and behavioral effects of cannabis. Other important questions are the impact of tolerance to the effects of cannabis on road safety as well as different routes of administration (e.g., edibles, vaped). It remains unclear if there is a dose-response relationship of cannabis to changes in driving. These and other key questions and issues are identified and discussed in this paper.

Presence of psychoactive substances in injured Belgian drivers

OBJECTIVE

To estimate the percentage of drivers involved in a traffic crash in Belgium who have alcohol and drugs in their blood.

METHODS

Blood samples of the drivers injured in a traffic crash and admitted to the emergency departments of 5 hospitals in Belgium between January 2008 and May 2010 were analyzed for ethanol (with an enzymatic method) and 22 other psychoactive substances (with ultra-performance liquid chromatography with tandem mass spectrometry or gas chromatography-mass spectrometry).

RESULTS

One thousand seventy-eight drivers were included in the study. Alcohol (≥0.1 g/L) was the most common substance (26.2%). A large majority of the drivers (64%) who were positive for alcohol had a blood alcohol concentration (BAC) ≥1.3 g/L (legal limit in Belgium: 0.5 g/L). These high BACs were most frequent among male injured drivers. Cannabis was the most prevalent illicit drug (5.3%) and benzodiazepines (5.3%) were the most prevalent medicinal drugs. Approximately 1 percent of the drivers were positive for cocaine and amphetamines. No drivers tested positive for illicit opioids. Medicinal drugs were more likely to be found among female drivers and drivers older than 35 years, and alcohol and illicit drugs were more likely to be found among male drivers and drivers younger than 35 years.

CONCLUSION

A high percentage of the injured drivers were positive for a psychoactive substance at the time of injury. Alcohol was the most common substance, with 80 percent of the positive drivers having a BAC ≥0.5 g/L. Compared to a roadside survey in the same area, drivers/riders with high BACs and combinations of drugs were overrepresented. Efforts should be made to increase alcohol and drug enforcement. The introduction of a categorization and labeling system might reduce driving under the influence of medicinal drugs by informing health care professionals and patients.

Alcohol and psychoactive drugs increased the pre-hospital mortality in 655 fall-related fatalities in Greece: a call for management protocols

INTRODUCTION

The frequency of alcohol and psychoactive drugs in fall-related fatalities and their effect on type, severity of injury and location of death constitute the subjects of this study.

METHODS

A retrospective analysis based on autopsy and toxicology compared demographics, location of injury; intention for the injury, height of fall, Abbreviated Injury Scale--90 (AIS-90), post-mortem Injury Severity Score (ISS), and location of death.

RESULTS

Amongst 655 fall-related fatalities screened for alcohol and psychoactive drugs 123 (18.8%) were classified in the positive toxicology group (PTG) and the remaining in the negative toxicology group (NTG). The median ages were 48 (16-94) years for the PTG and 62 (12-96) years for the NTG. The screened represent 31% of the national toll. The median height of fall was 7 m and the median blood alcohol concentration was 53 (1.5-630)mg/dl. Males were more likely to be included in the PTG than females (21.6 versus 13.6%; p = 0.014) as were the aged between 11 and 60 years. The odds of severe (AIS ≥ 3) head, thoracic, abdominal, extremity, and spine injuries were not influenced by toxicology status. Fatalities of the PTG were as likely to have severe trauma (ISS ≥ 16) as were fatalities of the NTG (93.5 versus 90.8%; p = 0.34). There was no significant difference of ISS between PTG (median ISS 43, range: 6-75) and NTG (median ISS 35, range: 3-75). Nevertheless, 76.4% of the subjects of the PTG died during the pre-hospital stage of care compared to 60.5% of the subjects of the NTG, which was highly significant (or = 2.80, p = 0.001) after controlling for confounders as age, gender, intention for injury, height of fall, and ISS.

CONCLUSIONS

In fall related trauma, alcohol and psychoactive drugs increased the risk of death during the pre-hospital stage by 2.80 times. This is strong evidence that specific protocols for their early management should be instituted.

The intriguing effects of ecstasy (MDMA) on cognitive function in mice subjected to a minimal traumatic brain injury (mTBI)

RATIONALE

The use of ecstasy (MDMA) among young adults has dramatically increased over the years. Since MDMA may impair the users' driving ability, the risk of being involved in a motor vehicle accident (MVA) is notably increased. Minimal traumatic brain injury (mTBI) a common consequence of MVAs-produces short- and long-term physical, cognitive, and emotional impairments.

OBJECTIVES

To investigate the effects of an acute dose of MDMA in mice subjected to closed head mTBI.

METHODS

Mice received 10 mg/kg MDMA 1 h prior to the induction of mTBI. Behavioral tests were conducted 7 and 30 days post-injury. In addition to the behavioral tests, phosphorylation of IGF-1R, ERK, and levels of tyrosine hydroxylase (TH) were measured.

RESULTS

mTBI mice showed major cognitive impairments in all cognitive tests conducted. No additional impairments were seen if mTBI was preceded by one dose of MDMA. On the contrary, a beneficial effect was seen in these mice. The western blot analysis of TH revealed a significant decrease in the mTBI mice. These decreases were reversed in mice that were subjected to MDMA prior to the trauma.

CONCLUSIONS

The presence of MDMA at the time of mTBI minimizes the alteration of visual and spatial memory of the injured mice. The IGF-1R pathway was activated due to mTBI and MDMA but was not the main contributor to the cognitive improvements. MDMA administration inverted the TH decreases seen after injury. We believe this may be the major cause of the cognitive improvements seen in these mice.

Motor vehicle collision fatalities involving alcohol and illicit drugs in Greece: the need for management protocols and a reassessment of surveillance

AIMS

The frequency and the effect of alcohol and illicit drugs on injury type, severity and location of death in motor vehicle collision (MVC) fatalities were investigated.

DESIGN

Retrospective case-control study based on autopsy and toxicology.

SETTINGS

Single faculty accepting referrals from Greater Athens and prefectures.

PARTICIPANTS

Consecutive pre-hospital and in hospital fatalities.

MEASUREMENTS

Demographics, toxicology, abbreviated injury scale (AIS), injury severity score (ISS), and location of death.

FINDINGS

Of the 1860 screened subjects, 612 (32.9%) constituted the positive toxicology group (PTG) for alcohol or illicit drugs or both and the 1248 (67.1%) the negative toxicology group (NTG). The median age was 34 (4-90) years for the PTG and 45 (3-97) years for the NTG. The PTG included significantly higher proportions of males and motorcyclists. The PTG had a 50% increased risk for a severe (AIS ≥3) cervical spine and 85% for a severe upper extremity injury, compared to the NTG. A total of 29.2% of the PTG and 22.4% of the NTG deaths were non-preventable (ISS=75). The frequency of severe trauma (ISS ≥16) was comparable between PTG and NTG (P=0.87). The PTG presented with a median ISS of 43 (6-75) versus 41 (2-75) of the NTG, hence without significant difference (P=0.11). The pre-hospital death rate was 77.8% for the PTG versus 58% of the NTG (P<0.001). The analysis confirmed that the odds of positive toxicology were considerably higher in the subjects who arrived dead at the hospital (OR 2.62, P <0.001).

CONCLUSIONS

In the greater Athens region, almost a third of motor vehicle collision-related fatalities involved alcohol, illicit drugs or both. Individuals screened positive for alcohol or drugs were 2.6 times more likely to die before hospital admission than those with a negative toxicology screen, despite comparable injury severity. Specific evidence-based management protocols and reassessment of surveillance are required.

Resource utilization and outcomes of intoxicated drivers

Background

The high risk behavior of intoxicated drivers, impaired reaction time, lack of seat belt use, and increased incidence of head injury raises questions of whether pre-hospital use of alcohol leads to a higher injury severity score and worse clinical outcomes. We therefore compared intoxicated and non-intoxicated drivers of motor vehicle crashes with respect to outcome measurements and also describe the resources utilized to achieve those outcomes at our Level 1 trauma center.

Methods

Retrospective descriptive study (Jan 2002-June 2007) of our trauma registry and financial database comparing intoxicated drivers with blood alcohol levels (BAC) > 80 mg/dl (ETOH > 80) with drivers who had a BAC of 0 mg/dl (ETOH = 0). Drivers without a BAC drawn or who had levels ranging from 1 mg/dL to 80 mg/dL were excluded. Data was collected on demographic information (age, gender, injury severity score or ISS), outcome variables (mortality, complications, ICU and hospital LOS, ventilator days) and resource utilization (ED LOS, insurance, charges, costs, payments). Statistical analysis: p < 0.05 vs. ETOH > 80; stratified chi square.

Results

Out of 1732 drivers, the combined study group (n = 987) of 623 ETOH = 0 and 364 ETOH > 80 had a mean age of 38.8 ± 17.9, ISS of 18.0 ± 12.1, and 69.8%% male. There was no difference in ISS (p = 0.67) or complications (p = 0.38). There was a trend towards decreased mortality (p = 0.06). The ETOH = 0 group had more patients with a prolonged ICU LOS (≥ 5 days), ventilator days (≥ 8 days), and hospital LOS (> 14 days) when compared to the ETOH > 80 group (p < 0.05). The ETOH > 80 group tended to be self pay (4.9% vs. 0.7%, p < 0.5) and less likely to generate payment for hospital charges (p < 0.5). Hospital charges and costs were higher in the ETOH = 0 group (p < 0.5).

Conclusions

The data suggests that intoxicated drivers may have better outcomes and a trend towards reduced mortality. They appeared to be less likely to have prolonged hospital LOS, ICU LOS, and ventilator days. We also observed that intoxicated drivers were more likely to be self-pay, less likely to have charges > $50K, and less likely to pay ≥ 90% of the charges. Further research using multivariable analysis is needed to determine if these apparent outcomes differences are driven by acute intoxication, and the tendency for endotracheal intubation and ICU admission, rather than injury severity.

The relationship between benzodiazepine use and traffic accidents: A systematic literature review

In many countries, benzodiazepines are the most commonly used and misused psychoactive medicinal drugs. Results of epidemiological studies investigating the association between benzodiazepine use and traffic accidents seem to be inconclusive or inconsistent at first sight. However, the outcome of epidemiological studies may be influenced by several methodological factors like study design, study population, exposure measurement, outcome definitions and possible confounders. Our objective was to conduct a systematic literature review of epidemiological studies that investigated the association between benzodiazepine use and traffic accidents, including related outcomes like culpability and injury or accident severity. We searched EMBASE, PubMed and Forensic Science Abstracts 3/0 (FORS) for references included in these databases at 1 June 2009 using the term 'benzodiazepines' in combination with 'driving performance' or 'accident risk' or 'traffic accident'. For inclusion in this review, the study design had to be comparative, include road users involved in accidents and provide specific data about benzodiazepines. Sixty-six studies were included in the review. The study populations varied from the general (driving) population, accident-involved road users with or without injury and persons admitted to a hospital to fatally injured accident-involved drivers. Exposure assessment was performed by using toxicological results, prescription data or questionnaires. The divergent study populations and comparison groups and the variety of methods used to express the outcome of interest hampered comparison between results. Evidence is growing that exposure to benzodiazepines is related to increased accident risk. The literature indicates that the greatest accident risk is associated with the use of long half-life benzodiazepines, increasing dosage and the first few weeks of use of benzodiazepines. Clear evidence of increased culpability associated with benzodiazepine use is scarce. More research has to be done to elucidate the relationship between benzodiazepine use and injury severity.

First nationwide study on driving under the influence of drugs in Switzerland

In Switzerland, a two-tier system based on impairment by any psychoactive substances which affect the capacity to drive safely and zero tolerance for certain illicit drugs came into force on 1 January 2005. According to the new legislation, the offender is sanctioned if Delta(9)-tetrahydrocannabinol THC is >or=1.5ng/ml or amphetamine, methamphetamine, 3,4-methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxyethylamphetamine (MDEA), cocaine, free morphine are >or=15ng/ml in whole blood (confidence interval+/-30%). For all other psychoactive substances, impairment must be proven in applying the so-called "three pillars expertise". At the same time the legal blood alcohol concentration (BAC) limit for driving was lowered from 0.80 to 0.50g/kg. The purpose of this study was to analyze the prevalence of drugs in the first year after the introduction of the revision of the Swiss Traffic Law in the population of drivers suspected of driving under the influence of drugs (DUID). A database was developed to collect the data from all DUID cases submitted by the police or the Justice to the eight Swiss authorized laboratories between January and December 2005. Data collected were anonymous and included the age, gender, date and time of the event, the type of vehicle, the circumstances, the sampling time and the results of all the performed toxicological analyses. The focus was explicitly on DUID; cases of drivers who were suspected to be under the influence of ethanol only were not considered. The final study population included 4794 DUID offenders (4243 males, 543 females). The mean age of all drivers was 31+/-12 years (range 14-92 years). One or more psychoactive drugs were detected in 89% of all analyzed blood samples. In 11% (N=530) of the samples, neither alcohol nor drugs were present. The most frequently encountered drugs in whole blood were cannabinoids (48% of total number of cases), ethanol (35%), cocaine (25%), opiates (10%), amphetamines (7%), benzodiazepines (6%) and methadone (5%). Other medicinal drugs such as antidepressants and benzodiazepine-like were detected less frequently. Poly-drug use was prevalent but it may be underestimated because the laboratories do not always analyze all drugs in a blood sample. This first Swiss study points out that DUID is a serious problem on the roads in Switzerland. Further investigations will show if this situation has changed in the following years.