Changing patterns of drug and alcohol use in fatally injured drivers in Washington State

Impacts of alcohol and opioid polysubstance use on road safety: Systematic review

Connections between substance use, impairment, and road safety have been frequently researched. Yet, little is known about how simultaneous use of opioids and alcohol affects road safety outcomes, which is an increasingly critical link within the current landscape of the substance use environment and public health. Lack of this understanding is partly due to testing complications and data limitations. We define polysubstance use here as alcohol and opioids consumed together or within a small-time window such that both are present in the system. This polysubstance use is on the rise and produces greater health risks than when the substances are consumed separately. Given the increasing rate of opioid use, high prevalence of alcohol use, and dangers of polysubstance use, we aim to synthesize literature on the prevalence and impact of this polysubstance on road safety-related outcomes. We performed a systematic review of studies published between 1974 and 2020 that examined opioid and alcohol use exposures and road safety-related outcomes. Out of 644 initial findings, 20 studies were included in this review. Outcomes included motor vehicle crash injuries, deaths, or driver culpability; suspected driving under the influence; and simulated driving performance. Evidence from multiple sources showed a significant rise, approximately 1% to 7%, in the prevalence of opioids among fatally injured drivers in the U.S. from 1995 to 2016. Information published on the simultaneous presence of opioids and alcohol in people involved in crashes was scarce. The limited available findings point toward an overlap where up to 30% of opioid-positive people involved in a crash were also positive for alcohol. Studies also suggest a possibly elevated risk presented by this polysubstance use relative to the substances used alone, though the majority of identified studies did not estimate this association. The synthesized research indicates that alcohol and opioid use is not uncommon and may be increasing among people involved in adverse driving events. More research and better data are needed to improve estimates of association with road traffic-related outcomes, potentially improving substance testing in current surveillance systems or using linked data sets and other novel data sources to improve estimates.

Everything Is Bigger in Texas: Alcohol Impaired Driving in Houston (2014-2018)

Driving while intoxicated (DWI) or driving under the influence of drugs (DUID) poses a continued public safety risk in Texas, which has one of the highest alcohol impaired traffic fatality rates. This study aimed to identify alcohol and drug use trends seen in DWI/DUID cases in the city of Houston from 2014 to 2018 to better understand the populations at risk. Blood samples submitted to the Houston Forensic Science Center (HFSC) were evaluated for blood alcohol concentration (BAC), drug concentrations and demographics. During the 5-year period, 12,682 Houston driver blood samples had a mean (median) BAC of 0.151 g/dL (0.167 g/dL) and age of 36.3 (34) years. Fifty percent of samples were white males. Seventy-five percent of samples were individuals aged 21 to 44 years. Between 2014 and 2018, the number of cases submitted nearly doubled, from approximately 2,000 cases per year to over 3,700. In 2014, 23% of cases submitted required further analysis per HFSC testing policy (drug screen and confirmation for DWI/DUID cases when BAC < 0.100 g/dL), which rose to 27% by 2018. Of those, 36% were polydrug cases, requiring two or more confirmation tests. Cannabinoids was the most common drug class detected (34% of cases analyzed for drugs), followed by benzodiazepines (25%), phencyclidine (20%), cocaine/metabolites (15%) and opioids (12%). Phencyclidine rose from the fifth-most commonly detected drug in 2014 to the second-most drug in 2018. Only 3% of all cases (n = 408) were negative for both alcohol and drugs. Communication between law enforcement and laboratory management is recommended to address growing caseload more effectively. The study limitations (e.g., limited scope of analysis) suggest the present data underestimated the full extent of impaired driving in Houston, indicating even more urgent needs for increasing resources and efforts to reduce this serious threat to public safety.

Driving Under the Influence of Drugs: When the Law Misses the Mark

According to Florida law, an individual is not guilty of driving under the influence of drugs unless impairment is observed and is due to one or more controlled drugs listed in the Florida Statutes. Many prescription drugs, over-the-counter drugs and novel psychoactive compounds that can cause significant impairment are not included in this list. Five other states within the USA including Alaska, Hawaii, Massachusetts, New York and Oregon have similar or other restrictive language in their impaired driving statutes. From January of 2007 to February of 2018, 1,344 blood specimens and 1,796 urine specimens were analyzed for drugs in impaired driving cases in Palm Beach County, Florida. Over the past 11 years, 21% (212 out of 1,028) of all drug-positive blood specimens and 47% (711 out of 1,527) of all drug-positive urine specimens contained at least one non-controlled drug, often mixed with controlled drugs. Despite documentation of observed impairment with the concurrent identification of impairing drugs, an impaired driving charge could not be supported due to the phrasing of the law in Florida. If the intent of drug-impaired driving laws is to improve safety by removing impaired drivers from the road, a more all-encompassing "any impairing drug" law would be more appropriate. Linking the charge to a drug possession law framework or using other restrictive language is not the most effective means to improve road safety.

Driving under the influence of drugs: Prevalence in road traffic accidents in Italy and considerations on per se limits legislation

OBJECTIVE

The objective of this study was to present the prevalence and concentrations of drugs in blood samples of drivers involved in road traffic accidents (RTAs) and to discuss the effects of adopting different concentration cutoff values proposed or applied in other European countries on the number of driving under the influence of drugs (DUID) offenses.

METHODS

Blood samples from drivers involved in RTAs in Padova province from 2014 to 2017 were analyzed for the presence of alcohol and drugs. The prevalence of positive subjects was reported for each substance adopting the limits of quantification (LOQs) of our laboratory and the concentration cutoff values proposed and/or used in other European countries. The reduction of cases of driving under the influence of illicit drugs in applying different cutoffs was calculated.

RESULTS

Four thousand four hundred forty-three blood samples were analyzed: 23.7% were positive for alcohol and 19.9% for psychoactive drugs, with prevalences of polydrug and alcohol-drug abuse of 4.5 and 6%, respectively. The most frequently detected drugs were cannabinoids (9.7%) and cocaine (7.2%), followed by benzodiazepines (4.1%), opiates (1.9%), and other opioids (1.7%). Barbiturates, amphetamines, and ketamine were identified in a much smaller number of cases. The overall decrease in DUID cases when adopting different cutoffs with respect to cases above the LOQs was between 8 and 84%. The adoption of high LOQs such as those used in the European Union's research project on Driving Under the Influence of Drugs, Alcohol and Medicines (DRUID) decreases the hypothetical number of DUID offenses by a quarter, and per se limits proposed as broadly equivalent to a blood alcohol concentration (BAC) between 0.2 and 0.8 g/L dramatically reduce the cases of DUID (cocaine -81%, cannabis -79%, opioids -97%, opiates -96%, and amphetamines -77%); no ketamine-positive samples were above the cutoff.

CONCLUSIONS

The implementation of high analytical limits or per se limits based on impairing concentrations in the Italian legislation could result in the prosecution of a much lower number of drugged drivers involved in RTAs, with a decrease from 25% to more than 80% depending on the limits.

Correlation between Blood and Oral Fluid Psychoactive Drug Concentrations and Cognitive Impairment in Driving under the Influence of Drugs

BACKGROUND

The effects of drugs on driving performance should be checked with drug concentration in the brain and at the same time with the evaluation of both the behavioural and neurophysiological effects. The best accessible indicator of this information is the concentration of the drug and/or metabolites in blood and, to a certain extent, oral fluid. We sought to review international studies on correlation between blood and oral fluid drug concentrations, neurological correlates and cognitive impairment in driving under the influence of drugs.

METHODS

Relevant scientific articles were identified from PubMed, Cochrane Central, Scopus, Web of Science, Science Direct, EMBASE up to April 2017.

RESULTS

Up to 2010, no epidemiological studies were available on this matter and International scientists suggested that even minimal amounts of parent drugs in blood and oral fluid could affect driving impairment. More recently, epidemiological data, systematic reviews and meta-analysis on drugged drivers allowed the suggestion of impairment concentration limits for the most common illicit drugs. These values were obtained comparing driving disability induced by psychotropic drugs with that of established blood alcohol limits. Differently from ethyl alcohol where both detection methods and concentration limits have been well established even with inhomogeneity of ranges within different countries, in case of drugs of abuse no official cut-offs have yet been established, nor any standardized analytical protocols.

CONCLUSION

Multiple aspects of driving performance can be differently affected by illicit drugs, and even if for few of them some dose/concentration dependent impairment has been reported, a wider knowledge on concentration/impairment relationship is still missing.

A Two-Year Study of Δ 9 Tetrahydrocannabinol Concentrations in Drivers; Part 2: Physiological Signs on Drug Recognition Expert (DRE) and non-DRE Examinations,

Whole blood samples were examined for ∆⁹ -Tetrahydrocannabinol (THC) over 2 years in drivers suspected of driving under the influence. Part one of the study examined the link between [THC] and performance on field sobriety tests. This portion examined objective signs, eye examinations and physiological indicators; and their relationship to the presence of THC. Several objective signs were excellent indicators of the presence of THC: red eyes (94%), droopy eyelids (85.6%), affected speech (87.6%), tongue coating (96.2%), and odor of marijuana (82.4%). About 63.6% of THC positive subjects had dialted pupils (room light). THC positive subjects had either rebound dilation or hippus in 88.8% of cases. Pulse and blood pressure (BP) were evaluated to determine any correlation with [THC]. An increased pulse rate correlated well to the presence of THC (88.5%), but not [THC]. BP did not correlate to [THC] and was also a poor indicator of THC in the blood (50% high).

23 years of toxicology testing fatally injured pilots: Implications for aviation and other modes of transportation

Use of over-the-counter, prescription, and illicit drugs is increasing in the United States (US). Many of these drugs are psychoactive and can affect the user's ability to safely operate a vehicle. However, data about drug use by vehicle operators is typically limited to a small proportion of operators and a short list of drugs. For instance, required testing for commercial vehicle operators following most accidents is limited to a urine test for 11 drugs. By comparison, the Federal Aviation Administration (FAA), routinely tests fatally injured pilots' blood and tissues for hundreds of compounds. This study used the results from these tests to assess drug use in aviation.

METHODS

Using matched data from the FAA's Civil Aerospace Medical Institute toxicology database and the National Transportation Safety Board's (NTSB's) aviation accident database, this study examined trends in the prevalence of over-the-counter, prescription, and illicit drugs identified in toxicology tests of fatally injured pilots between 1990 and 2012. Cases that failed to match or where toxicology testing had not been performed were excluded. Pilots identified by the NTSB investigation as being the "flying pilot" at the time of the accident and results from blood or tissues were included. Toxicology results for ethanol and other alcohols were not included. Positive test results were categorized by drug type and potential for causing impairment. Analysis used SPSS Version 19.1 to perform linear by linear chi-squared statistics.

RESULTS

The study included 6677 pilots or 87% of the eligible subjects. The large majority were male (98%) and flying general aviation operations (96%) at the time of their fatal accident. There were increasing trends in pilots' use of all drugs, potentially impairing drugs, drugs used to treat potentially impairing conditions, drugs designated as controlled substances, and illicit drugs. The most common potentially impairing drug pilots had used was diphenhydramine, a sedating antihistamine that is an active ingredient in many over-the-counter allergy formulations, cold medicines, and sleep aids in the US. Although evidence of illicit drug use was found only in a small number of cases, the percentage of pilots testing positive for marijuana use increased during the study period, mostly in the last 10 years.

Intentional misuse of over-the-counter medications, mental health, and polysubstance use in young adults

In recent years, the non-medical use of prescription drugs (without a doctor's prescription) has increased dramatically. Less attention has been paid to the intentional misuse of over-the-counter (OTC) medications. Misuse of OTC medications has negative health consequences similar to those of illicit drugs, including psychosis, tachycardia, seizures and agitation. When mixed with alcohol or other drugs, these medications can also be dangerous: OTC-related emergency room visits increased 70% from 2004 to 2008. This study examined the intentional misuse of OTC medications, the non-medical use of prescription drugs, the use of alcohol and illicit drugs, and psychological factors in two samples of young adults (ages 18-25) from different areas of the United States (Total N = 1,197). Overall, 18.6% of the Colorado sample and 13.0% of the Virginia sample reported lifetime misuse of an OTC medication. Participants who reported misusing OTC medications were also significantly more likely to report using marijuana, ecstasy, cocaine, and non-medical use of prescription analgesics, stimulants, anxiolytics, and sedatives. Participants who reported misusing OTC medications were more than twice as likely to report hazardous alcohol use, relative to individuals who denied misusing OTC medications. Individuals who had misused OTC medications scored significantly higher in sensation seeking and hopelessness and reported more symptoms of depression, anxiety, and somatic distress, relative to those who denied OTC misuse. Results suggest that a considerable minority of young adults are jeopardizing their health with the misuse of OTC medications as part of a pattern of polysubstance use.

Trends in drug use among drivers killed in U.S. traffic crashes, 1999-2010

OBJECTIVE

Driving under the influence of drugs is a global traffic safety and public health concern. This trend analysis examines the changes in general drug usage other than alcohol, broad categories, and typical prescription and illegal drugs among drivers fatally injured in motor vehicle crashes from 1999 to 2010 in the U.S.

METHODS

Data from the Fatality Analysis Reporting System were analyzed from 1999 to 2010. Drug prevalence rates and prevalence ratios (PR) were determined comparing rates in 2009-2010 to 1999-2000 using a random effects model. Changes in general drug usage, broad categories, and representative prescription and illegal drugs including, methadone, oxycodone, hydrocodone, barbiturates, benzodiazepines, and cocaine, were explored.

RESULTS

Comparing 2009-2010 to 1999-2000, prevalence of drug usage increased 49% (PR=1.49; 95% confidence interval [CI] 1.42, 1.55). The largest increases in broad drug categories were narcotics (PR=2.73; 95% CI 2.41, 3.08), depressants (PR=2.01; 95% CI 1.80, 2.25), and cannabinoids (PR=1.99; 95% CI 1.84, 2.16). The PR were 6.37 (95% CI 5.07, 8.02) for hydrocodone/oxycodone, 4.29 (95% CI 2.88, 6.37) for methadone, and 2.27 (95% CI 2.00, 2.58) for benzodiazepines. Barbiturates declined in rate over the 12-year period (PR=0.53; 95% CI 0.37, 0.75). Cocaine use increased until 2005 then progressively declined, though the rate remained relatively unchanged (PR=0.94; 95% CI 0.84, 1.06).

CONCLUSIONS

While more drivers are being tested and found drug-positive, there is evidence that a shift from illegal to prescription drugs may be occurring among fatally injured drivers in the U.S. Driving under the influence of prescription drugs is a growing traffic concern.

The effects of a new traffic safety law in the Republic of Serbia on driving under the influence of alcohol

The aim of the study presented here has been to see what the effects of the new traffic safety law are, 2 years into its initial implementation, on driving under the influence of alcohol. Until the end of 2009, the legal limit for blood concentration for drivers in Serbia was 0.5g/l; however, the new traffic safety law stipulates the new limit to be 0.3g/l. A retrospective autopsy study was performed over a 6-year period (from 2006 to 2011) whose sample covered cases of fatally injured drivers who had died at the scene of the incident, before being admitted to hospital. A total of 161 fatally injured drivers were examined for their blood alcohol concentration. The average age for these drivers was 40.2±15.4 years, with a significant male predominance of 152 men to 9 women (χ(2)=152.000, p<0.001). This study has shown no decrease in the ratio of drivers under the influence of alcohol vs. all drivers (Pearson χ(2)=4.415, df=5, p=0.491), nor in the number of drivers under the influence of alcohol (Pearson χ(2)=6.629, df=5, p=0.250), nor a decrease in the mean blood alcohol concentration in drivers (1.72±0.87 vs. 1.68±0.95g/l, t=0.177, df=80, p=0.860). The conclusion of this study is that the new law has had a limited effect on driving under the influence of alcohol, which still remains one of the major human factors, responsible for road-traffic crashes in Serbia.

Drivers under the influence of drugs of abuse: quantification of cocaine and impaired driving

In recent years, the interest in oral fluid as a biological matrix has significantly increased, particularly for detecting driving under the influence of drugs. In this study, the concentration of cocaine and its relationship with clinical symptoms in drivers suspected of driving under the influence of drugs was evaluated. A total of 154 samples of oral fluid, which tested positive for cocaine in previous immunoassay screening, Cozart Drug Detector System, were confirmed using gas chromatography/mass spectrometry method. In Catalonia, during 2007-2010, there were 1791 samples positive for cocaine among a total of 3468 samples taken from drivers who tested positive for any drug of abuse. The evaluation of clinical symptoms was through a questionnaire that was filled in by the police officers who collected the samples. The mean concentration of cocaine was 4.11 mg/l and median concentration was 0.38 mg/l (range 0.01-345.64 mg/l). Clinical impairment symptoms such as motor coordination, walking, speech, mood and state of pupils were not significant. The testing of oral fluids presents fewer ethical problems than blood or urine.

The effect of d,l-methamphetamine on simulated driving performance

RATIONALE

Illicit drugs such as methamphetamine are commonly abused drugs that have also been observed to be prevalent in drivers injured in road accidents. The exact effect of methamphetamine or its specific isomers on driving and driving behaviour have yet to be thoroughly investigated.

METHODS

Twenty healthy recreational illicit stimulant users (ten males, ten females), aged between 21 and 34 years (mean = 24.3 years, SD = 3.4 years), attended two testing sessions involving oral consumption of 0.42 mg/kg d,l-methamphetamine or a matching placebo. The drug administration was counterbalanced, double-blind, and medically supervised. At each session, driving performance was assessed 2.5 h post-drug administration.

RESULTS

Mean blood and saliva d,l-methamphetamine concentrations of approximately 90 and 400 ng/ml, respectively, at 2 h and 95 and 475 ng/ml at 3 h were observed. These levels of d,l-methamphetamine were found not to significantly impair, or improve, driving performance at the 2.5-h post-drug administration time point.

CONCLUSIONS

The findings of this study illustrate that d,l-methamphetamine has no significant effect on simulated driving performance.

Drunk versus drugged: how different are the drivers?

BACKGROUND

Driving under the influence (DUI) of drugs is increasing in the U.S., but little is known about the differences based on their patterns of use and abuse of alcohol and other drugs.

METHODS

This paper uses a large dataset to study patients admitted to Texas substance abuse treatment programs with one or more past-year DUI arrests. t-Tests are used for comparisons between normally distributed continuous data and chi square for categorical data.

RESULTS

First-time DUI offenders not only differ from those reporting more than one past-year DUI, but they differ among themselves in terms of demographics, treatment participation, substance use problems, and mental health disorders. Those with primary problems with methamphetamine, crack cocaine, powder cocaine, other opiates, sedatives, and heroin reported more days of problems and more daily use than those with problems with alcohol, while offenders with primary problems with cannabis were less impaired.

CONCLUSIONS

The most impaired clients were less likely to be referred to treatment from the justice system, and the differences in drug and alcohol offenders show the need to tailor approaches with education and treatment programs. More attention should be given to the needs of drivers impaired through use of prescription drugs such as the opiates and sedatives, as well as female drivers, and the role of acculturation should be recognized in programs for Hispanic drivers. In addition, specific programs should be targeted to young cannabis abusers and underage offenders. All first-time DUI arrestees should be assessed for their levels of impairment.

The need for drugged driving per se laws: a commentary

OBJECTIVE

Triggered by the new federal commitment announced by the Office of National Drug Control Policy (ONCDP) to encourage states to enact drugged driving per se laws, this article reviews the reasons to establish such laws and the issues that may arise when trying to enforce them.

METHODS

A review of the state of drunk driving per se laws and their implications for drugged driving is presented, with a review of impaired driving enforcement procedures and drug testing technology.

RESULTS

Currently, enforcement of drugged driving laws is an adjunct to the enforcement of laws regarding alcohol impairment. Drivers are apprehended when showing signs of alcohol intoxication and only in the relatively few cases where the blood alcohol concentration of the arrested driver does not account for the observed behavior is the possibility of drug impairment pursued. In most states, the term impaired driving covers both alcohol and drug impairment; thus, driver conviction records may not distinguish between the two different sources of impairment. As a result, enforcement statistics do not reflect the prevalence of drugged driving.

CONCLUSIONS

Based on the analysis presented, this article recommends a number of steps that can be taken to evaluate current drugged driving enforcement procedures and to move toward the enactment of drug per se laws.

Effects of alcohol (BAC 0.5‰) and ecstasy (MDMA 100 mg) on simulated driving performance and traffic safety

RATIONAL

An increasing number of fatal road-accidents have been reported in which ecstasy was found in the blood of drivers. Although, ecstasy is frequently found to have been used in combination with alcohol, studies on the acute effects of ecstasy co-administered with alcohol on driving performance are relatively rare.

OBJECTIVE

The present study was designed to establish the extent of driver impairment as a consequence of ecstasy or combined ecstasy and alcohol use as compared to driving under the influence of 0.3‰, 0.5‰ and 0.8‰ alcohol. Furthermore, subjective performance was also assessed.

RESULTS

Alcohol and ecstasy mainly influenced automated driving performance such as lateral and speed control. However, small to no effects of the substances were found on more complex driving behaviour. Overall, variance within the different driving measures was high especially when participants were treated with 3.4-methylenedioxy-methamphetamine (MDMA) and alcohol. Furthermore, equivalence testing showed that combined use may lead to impaired driving for some, but not all, drivers. Participants rated their own performance to be slightly worse than normal in both studies. Since driving was actually seriously deteriorated, this was a falsely positive assessment of their condition.

CONCLUSIONS

The dissociation between subjective perceptions and objective performance decrements are important notions for traffic safety since this may affect a driver's judgement of whether or not it is safe to drive. For example, an intoxicated individual might decide to drive because the feelings of alertness caused by MDMA cloud the impairing effects of other drugs such as alcohol, thereby creating a potentially serious risk for traffic safety.

An evaluation of the narrowing gender gap in DUI arrests

Although males account for the vast majority of those convicted of driving under the influence of alcohol and/or other drugs (DUI), female DUI convictions have increased over the past two decades. In this study, we examined the ratio of males-to-females who were court-mandated between the years 1992 and 2008 to attend the Mississippi Alcohol Safety Education Program (MASEP), a DUI intervention program in Mississippi. The data for this study came from MASEP records; the Behavioral Risk Factor Surveillance System (BRFSS); the Uniform Crime Reports (UCR); the Treatment Episode Data Set (TEDS); the National Household Travel Survey (NHTS); and National Highway Traffic Safety Administration (NHTSA), an agency within the US Department of Transportation. Augmented Dickey-Fuller (ADF) tests were used to assess the nature (i.e., convergence, divergence, or stability) of this trend and to identify predictors. The results showed that, over the 17-year period, the gender gap in DUI convictions, self-reported history of prior arrest, official drug arrests, and substance abuse treatment admissions has narrowed considerably. Results from the autoregressive integrated moving average (ARIMA) models show that three factors account for increases in the proportion of women mandated to attend MASEP: self-reported arrest prior to the DUI conviction, female admissions to substance abuse treatment, and annual miles driven. Changes in both women's behavior and law enforcement practices have increased female exposure to DUI arrests and narrowed the gender gap in DUI convictions.

Toxicological investigations of drivers killed in road traffic accidents in Norway during 2006-2008

AIM

To study the results from the toxicological investigations of drivers of cars and vans who were fatally injured in road traffic accidents in 2006-2008 and discuss the findings in relation to the proposed legal limits and impairment thresholds for drugs.

METHODS

Analyses for alcohol, illegal drugs and psychoactive medicinal drugs were performed by the Norwegian Institute of Public Health. Information on type of accident (single or multiple vehicles) and type of road (urban or rural) was obtained from Statistics Norway.

RESULTS

Toxicological analyses were requested for 59% of the fatally injured drivers. Drivers involved in single vehicle accidents were more often subject to toxicological investigations, so were also young male drivers and drivers killed on urban roads. Alcohol or drugs were found in concentrations above the current (for alcohol) or proposed (for drugs) legal limits in samples from 37.8% of the drivers; from 64.3% those killed in single-vehicle accidents and 17.9% of those killed in multiple-vehicle accidents. In total, alcohol was found in 25.0%, illicit drugs in 10.2%, and psychoactive medicinal drugs in 13.8% of the samples. Combinations of alcohol and drugs were found in 5.1% and multiple drugs without alcohol in 6.1% of the samples. The prevalence of alcohol or drugs was higher in samples from males than females, higher in samples from young drivers, and higher in samples from drivers killed during weekends. Two thirds of the drivers with alcohol or drug concentrations above the current or proposed legal limits had concentrations above the proposed high impairment threshold. About 60% of the latter ones were impaired by alcohol only, 20% by drugs in combination with alcohol, and 20% by drugs only, mainly due to multi-drug use.

CONCLUSION

The use of alcohol or drugs before driving was a significant contributing factor in fatal road traffic accidents, particularly in single vehicle accidents, and particularly among young male drivers. Alcohol was the most significant intoxicant, but multi-substance use was also significantly prevalent. The majority of the drivers with alcohol or drug findings were strongly impaired.

Gasoline prices and their relationship to drunk-driving crashes

This study investigates the relationship between changing gasoline prices and drunk-driving crashes. Specifically, we examine the effects of gasoline prices on drunk-driving crashes in Mississippi by several crash types and demographic groups at the monthly level from 2004 to 2008, a period experiencing great fluctuation in gasoline prices. An exploratory visualization by graphs shows that higher gasoline prices are generally associated with fewer drunk-driving crashes. Higher gasoline prices depress drunk-driving crashes among young and adult drivers, among male and female drivers, and among white and black drivers. Results from negative binomial regression models show that when gas prices are higher, there are fewer drunk-driving crashes, particularly among property-damage-only crashes. When alcohol consumption levels are higher, there are more drunk-driving crashes, particularly fatal and injury crashes. The effects of gasoline prices and alcohol consumption are stronger on drunk-driving crashes than on all crashes. The findings do not vary much across different demographic groups. Overall, gasoline prices have greater effects on less severe crashes and alcohol consumption has greater effects on more severe crashes.

The prevalence of drugs in motor vehicle accidents and traffic violations in Shanghai and neighboring cities

The objective of this study was to determine the prevalence of psychoactive drug use among motor vehicle drivers in Shanghai and its neighboring cities. We selected 10,002 drivers involved in a traffic accident or violation between 2007 and 2008 in Shanghai, Suzhou and Wuxi. We checked for the presence of psychoactive drugs from blood samples using liquid chromatography tandem mass spectrometry (LC-MS-MS). Of the 10,002 drivers, 10.5% tested positive for drugs (excluding alcohol). Cold medicines were the most frequently detected drugs including chlorpheniramine (4.78%), pseudoephedrine (2.15%) and paracetamol (1.32%). The use of multiple cold medicines was common. Illegal drugs such as methamphetamine (0.15%), ketamine (0.03%) and MDMA (0.01%) were also detected. The prevalence of psychoactive drugs among drivers involved in traffic accidents or violations in Shanghai and its neighboring cities was lower compared to previous reports in Europe. Furthermore, cannabis--which has been reported to be the most widely used psychoactive drug after alcohol--was not commonly encountered among Shanghai drivers.

Applying Stafford and Warr's reconceptualization of deterrence theory to drug driving: can it predict those likely to offend?

In December 2007, random roadside drug testing commenced in Queensland, Australia. Subsequently, the aim of this study was to explore the preliminary impact of Queensland's drug driving legislation and enforcement techniques by applying Stafford and Warr's [Stafford, M.C., Warr, M., 1993. A reconceptualization of general and specific deterrence. Journal of Research in Crime and Delinquency, 30, 123-135] reconceptualization of deterrence theory. Completing a comprehensive drug driving questionnaire were 899 members of the public, university students, and individuals referred to a drug diversion program. Of note was that approximately a fifth of participants reported drug driving in the past six months. Additionally, the analysis indicated that punishment avoidance and vicarious punishment avoidance were predictors of the propensity to drug drive in the future. In contrast, there were indications that knowing of others apprehended for drug driving was not a sufficient deterrent. Sustained testing and publicity of the legislation and countermeasure appears needed to increase the deterrent impact for drug driving.

Role of the serotonergic system in reduced pulmonary function after exposure to methamphetamine

Although use of methamphetamine (MA) by smoking is the fastest growing method of administration, very limited data are available describing the effects of smoked MA. Using a murine inhalation exposure system, we explored the pulmonary effects of low-dose acute inhalation exposure to MA vapor (smoke). Inhalation of MA vapor resulted in transiently reduced pulmonary function, as measured by transpulmonary resistance, dynamic compliance, and whole-body plethysmography compared with unexposed control animals. These changes were associated with an approximately 34% reduction in serotonin (5-hydroxytryptamine [5-HT]) metabolism/inactivation to 5-hydroxyindolacetic acid, and a nearly 40% reduction in monoamine oxidase (MAO)-A activity in the lung. Pretreatment of mice with a selective 5-HT reuptake inhibitor completely ablated the MA-induced changes in pulmonary function, confirming a key role for the 5-HT transporter (serotonin transporter [SERT]) and the serotonergic system in this effect. Immunofluorescent staining of mouse lung tissue confirmed high expression of SERT in airway epithelial cells. Using mouse airway epithelial cell line, LA-4, and purified human MAO-A, it was demonstrated that MA impedes 5-HT metabolism through direct inhibition of MAO-A activity in vitro. Together, these data demonstrate that low-dose exposure to MA results in reduced pulmonary function mediated via SERT and subsequent perturbation of 5-HT metabolism in the lung. This supports a role for the serotonergic system in MA-mediated pulmonary effects.

A systematic review of research examining benzodiazepine-related mortality

PURPOSE

This paper will review literature examining the association of benzodiazepine use and mortality.

METHODS

An extensive literature review was undertaken to locate all English-language published articles that examine mortality risk associated with use of benzodiazepines from 1990 onwards.

RESULTS

Six cohort studies meeting the criteria above were identified. The results were mixed. Three of the studies assessed elderly populations and did not find an increased risk of death associated with benzodiazepine use, whereas another study of the general population did find an increased risk, particularly for older age groups. A study of a middle aged population found that regular benzodiazepine use was associated with an increased mortality risk, and a study of 'drug misusers' found a significant relationship between regular use of non-prescribed benzodiazepines and fatal overdose. Three retrospective population-based registry studies were also identified. The first unveiled a high relative risk (RR) of death due to benzodiazepine poisoning versus other outcomes in patients 60 or older when compared to those under 60. A positive but non-significant association between benzodiazepine use and driver-responsible fatalities in on-road motor vehicle accidents was reported. Drug poisoning deaths in England showed benzodiazepines caused 3.8% of all deaths caused by poisoning from a single drug.

CONCLUSION

On the basis of existing research there is limited data examining independent effects of illicit benzodiazepine use upon mortality. Future research is needed to carefully examine risks of use in accordance with doctors' prescriptions and extra-medical use.

Risk factors for depression in truck drivers

OBJECTIVE

Depression is a major public health problem. Work stress is associated with depression and workers whose jobs impose high levels of psychological demands, such as truck drivers, may be at increased risk. The aim of this study was to investigate the prevalence and correlates of depression in truck drivers.

METHOD

This was a cross-sectional study of 300 male truck drivers. Presence and severity of depression were assessed by the Mini International Neuropsychiatric Interview followed by the Beck Depression Inventory Short Form. Relevant demographic, clinical and occupational data were collected using a purpose-built questionnaire.

RESULTS

The prevalence of depression among truck drivers was 13.6%. Multivariate analysis showed that being 45 years or older had a protective effect (OR=0.19; P=0.02), whereas low educational level (OR=3.03; P=0.01), use of stimulants (OR=5.03; P<0.01) and wage-earning (OR=2.84; P=0.01), as opposed to self-employment, increased the risk for depression.

CONCLUSIONS

Truck drivers are at increased risk for depression when compared to the general population. Efforts to increase awareness of this problem and to limit the use of stimulants, as well as measures to improve job satisfaction, particularly among the wage-earning drivers, may have a positive impact on mental health in these workers.

Alcohol and drugs in fatally and non-fatally injured motor vehicle drivers in northern Sweden

Alcohol and drugs are important risk factors for traffic injuries, a major health problem worldwide. This prospective study investigated the epidemiology and the presence of alcohol and drugs in fatally and hospitalized non-fatally injured drivers of motor vehicles in northern Sweden. During a 2-year study period, blood from fatally and hospitalized non-fatally injured drivers was tested for alcohol and drugs. The study subjects were recruited from well-defined geographical areas with known demographics. Autopsy reports, medical journals, police reports, and toxicological analyses were evaluated. Of the fatally injured, 38% tested positive for alcohol and of the non-fatally 21% tested positive; 7% and 13%, respectively, tested positive for pharmaceuticals with a warning for impaired driving; 9% and 4%, respectively, tested positive for illicit drugs. The most frequently detected pharmaceuticals were benzodiazepines, opiates, and antidepressants. Tetrahydrocannabinol was the most frequently detected illicit substance. No fatally injured women had illegal blood alcohol concentration. The relative proportion of positively tested drivers has increased and was higher than in a similar study 14 years earlier. This finding indicates that alcohol and drugs merit more attention in future traffic safety work.

Trends in driving under the influence of drugs: a register-based study of DUID suspects during 1977-2007

Our aim was to describe the incidence and trends of driving under the influence of drugs (DUID) and to examine the main drug findings and their trends in suspected DUID cases in Finland. A register-based study was conducted of all suspected DUID cases during 1977-2007. The data included 31,963 DUID offenders apprehended by the police with a positive finding for illicit/licit drug impairing driving performance. Toxicological results were analyzed in blood and/or urine specimens in one central laboratory. The incidence of suspected DUID cases increased 18-fold during 1977-2007. Most of the suspects were men (89.7%). However, the male-female ratio decreased from 13.9 to 7.3. The mean age decreased from 36.2 years in 1977 to 29.9 years in 2001 but has since reincreased. Most often found substances were benzodiazepines (75.7%), amphetamines (46.0%), cannabinoids (27.7%) and opioids (13.8%). Most common illicit drugs, amphetamines and cannabinoids, started to appear at the end of the 1980s. Poly-drug findings were common (77.1%). Suspected DUID cases have increased sharply after the introduction of a zero tolerance law, especially in regard to amphetamines. DUID is an increasing problem in Finland, and needs serious attention.

Acute inhalation exposure to vaporized methamphetamine causes lung injury in mice

Methamphetamine (MA) is currently the most widespread illegally used stimulant in the United States. Use of MA by smoking is the fastest growing mode of administration, which increases concerns about potential pulmonary and other medical complications. A murine exposure system was developed to study the pulmonary affects of inhaled MA. Mice were exposed to 25-100 mg vaporized MA and assessments were made 3 h following initiation of exposure to model acute lung injury. Inhalation of MA vapor resulted in dose-dependent increases in MA plasma levels that were in the range of those experienced by MA users. At the highest MA dose, histological changes were observed in the lung and small but significant increases in lung wet weight to body weight ratios (5.656 +/- 0.176 mg/g for the controls vs. 6.706+/- 0.135 mg/g for the 100 mg MA-exposed mice) were found. In addition, there was 53% increase in total protein in bronchoalveolar lavage (BAL) fluid, greater than 20% increase in albumin levels in the BAL fluid, greater than 2.5-fold increase in lactate dehydrogenase levels in the BAL fluid, and reduced total BAL cell numbers (approximately 77% of controls). Levels of the early response cytokines tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 were dose-dependently increased in BAL fluid of MA-exposed mice. Exposure to 100 mg MA significantly increased free radical generation in the BAL cells to 107-146% of controls and to approximately 135% of the controls in lung tissue in situ. Together, these data show that acute inhalation exposure to relevant doses of volatilized MA is associated with elevated free radical formation and significant lung injury.

High re-arrest rates among drug-impaired drivers despite zero-tolerance legislation

BACKGROUND

A zero-tolerance law for driving under the influence of drugs (DUID) in Sweden led to a 10-fold increase in the number of cases submitted by the police for toxicological analysis. The statutory blood-alcohol concentration (BAC) limit for driving is 0.2 mg/g ( approximately 0.02 g%).

METHODS

An in-house database (TOXBASE) was used to investigate re-arrests for impaired driving over 4 years (2001-2004), which comprised 36,799 cases. The age, gender, re-arrest rate of the offenders and the concentrations of ethanol and amphetamine in blood samples were evaluated.

RESULTS

We found that 44% of individuals (N=16,277) re-offended 3.2 times on average (range 1-23 arrests). Between 85 and 89% of first-time offenders were men and there was also a male dominance among the recidivists (88-93%). The mean age of drunken drivers was approximately 40 years compared with approximately 35 years for driving under the influence of amphetamine, which was the drug identified in 50-60% of DUID cases, either alone or together with other licit or illicit drugs. The median BAC was 1.5mg/g ( approximately 0.15 g%), which suggests a dominance of heavy drinkers. The median BAC was even higher in recidivists (1.6-1.7 mg/g). The median concentration of amphetamine in blood was 1.0 mg/L in recidivists compared with 0.5mg/L in the first-time offenders. About 14% of drunken drivers re-offended 1-10 times compared with 68% of DUID suspects, who were re-arrested 1-23 times. People with only a scheduled prescription drug in blood were re-arrested much less frequently ( approximately 17%) compared with those taking illicit drugs (68%).

CONCLUSIONS

The appreciable increase in number of arrests for DUID after a zero-tolerance law might reflect a heightened enthusiasm by the police authorities armed with knowledge that a prosecution is easier to obtain. Zero-tolerance laws do not deter people from impaired driving judging by the high re-arrest rates. During the sentencing of hardcore offenders, the courts should give more consideration to the underlying substance abuse problem.

Driving under the influence of cannabis: a 10-year study of age and gender differences in the concentrations of tetrahydrocannabinol in blood

BACKGROUND

Delta(9)-Tetrahydrocannabinol (THC) is the major psychoactive constituent of cannabis and its various preparations. Increasing use of cannabis for recreational purposes has created a problem for road-traffic safety. This paper compares age, gender and the concentrations of THC in blood of individuals apprehended for driving under the influence of drugs (DUID) in Sweden, where a zero-tolerance law operates.

MEASUREMENTS

Specimens of blood or urine were subjected to a broad screening analysis by enzyme immunoassay methods. THC positives were verified by analysis of blood by gas chromatography-mass spectrometry (GC-MS) with a deuterium-labelled internal standard (d(3)-THC). All toxicology results were entered into a database (TOXBASE) along with the age and gender of apprehended drivers.

FINDINGS

Over a 10-year period (1995-2004), between 18% and 30% of all DUID suspects had measurable amounts of THC in their blood (> 0.3 ng/ml) either alone or together with other drugs. The mean age [+/- standard deviation (SD)] of cannabis users was 33 +/- 9.4 years (range 15-66 years), with a strong predominance of men (94%, P < 0.001). The frequency distribution of THC concentrations (n = 8794) was skewed markedly to the right with mean, median and highest values of 2.1 ng/ml, 1.0 ng/ml and 67 ng/ml, respectively. The THC concentration was less than 1.0 ng/ml in 43% of cases and below 2.0 ng/ml in 61% of cases. The age of offenders was not correlated with the concentration of THC in blood (r = -0.027, P > 0.05). THC concentrations in blood were higher when this was the only psychoactive substance present (n = 1276); mean 3.6 ng/ml, median 2.0 ng/ml compared with multi-drug users; mean 1.8 ng/ml, median 1.0 ng/ml (P < 0.001). In cases with THC as the only drug present the concentration was less than 1.0 ng/ml in 26% and below 2.0 ng/ml in 41% of cases. The high prevalence of men, the average age and the concentrations of THC in blood were similar in users of illicit drugs (non-traffic cases).

CONCLUSIONS

The concentration of THC in blood at the time of driving is probably a great deal higher than at the time of sampling (30-90 minutes later). The notion of enacting science-based concentration limits of THC in blood (e.g. 3-5 ng/ml), as discussed in some quarters, would result in many individuals evading prosecution. Zero-tolerance or limit of quantitation laws are a much more pragmatic way to enforce DUID legislation.

Concentrations of cocaine and its major metabolite benzoylecgonine in blood samples from apprehended drivers in Sweden

Cocaine and its major metabolite benzoylecgonine (BZE) were determined in blood samples from people arrested in Sweden for driving under the influence of drugs (DUID) over a 5-year period (2000-2004). Venous blood or urine if available, was subjected to a broad toxicological screening analysis for cannabis, cocaine metabolite, amphetamines, opiates and the major benzodiazepines. Verification and quantitative analysis of cocaine and BZE in blood was done by gas chromatography-mass spectrometry (GC-MS) at limits of quantitation (LOQ) of 0.02mg/L for both substances. Over the study period 26,567 blood samples were analyzed and cocaine and/or BZE were verified in 795 cases (3%). The motorists using cocaine were predominantly men (>96%) with an average age of 28.3+/-7.1 years (+/-standard deviation, S.D.). The concentration of cocaine was below LOQ in 574 cases although BZE was determined at mean, median and highest concentrations of 0.19mg/L, 0.12mg/L and 1.3mg/L, respectively. In 221 cases, cocaine and BZE were together in the blood samples at mean and (median) concentrations of 0.076mg/L (0.05mg/L) and 0.859mg/L (0.70mg/L), respectively. The concentrations of BZE were always higher than the parent drug; mean BZE/cocaine ratio 14.2 (median 10.9) range 1-55. Cocaine and BZE were the only psychoactive substances reported in N=61 cases at mean (median) and highest concentrations of 0.095 (0.07) and 0.5mg/L for cocaine and 1.01 (0.70) and 3.1mg/L for BZE. Typical signs of drug influence noted by the arresting police officers included bloodshot and glossy eyes, agitation, difficulty in sitting still and incoherent speech.

Predominance of illicit drugs and poly-drug use among drug-impaired drivers in Sweden

OBJECTIVE

After Sweden's zero-tolerance law came into force (1 July 1999), the number of cases of driving under the influence of drugs (DUID) submitted by the police for toxicological analysis increased more than 10-fold. This prompted an in-depth investigation into the kinds of drugs used by DUID offenders, whether licit or illicit, and the frequency of their occurrence.

METHODS

All blood samples from DUID suspects sent by the police for toxicological analysis over a 4-year period (2001-2004) were investigated (N = 22,777 cases). Specimens of blood or urine were subjected to a broad screening analysis by immunoassay methods aimed at detecting amphetamines, cannabis, opiates, cocaine metabolite, and the major benzodiazepines. All positive results from the screening stage were verified by use of more specific analytical methods (e.g., GC-MS, LC-MS, GC-FID, and GC-NPD).

RESULTS

Between 80 and 85% of all the blood samples contained at least one banned substance and many contained two or more therapeutic and/or illicit drugs. About 15% of cases were negative for drugs, although these frequently (30-50%) contained ethanol above the legal limit for driving in Sweden, which is 0.20 mg/g (0.02 g%). Amphetamine was the most prominent illicit drug seen in 55-60% of cases either alone or together with other drugs of abuse. Stimulants like cocaine and/or its metabolite were infrequently encountered ( approximately 1.2% of cases). The next most prevalent illicit drug was cannabis, with positive results for tetrahydrocannabinol (THC) in blood either alone ( approximately 4%) or together with other psychoactive substances ( approximately 20%). Morphine, codeine, and/or 6-acetyl morphine were identified in approximately 2% of all DUID suspects, being indicative of heroin abuse. The major prescription drugs identified in blood were benzodiazepines (10%) as exemplified by diazepam, alprazolam, nitrazepam, and flunitrazepam. Drugs for treating insomnia, zolpidem and zopiclone, were also identified in blood samples from DUID suspects over the study period. Other therapeutic agents were encountered in only 1-2% of all cases.

CONCLUSIONS

The dramatic increase in DUID after the zero-tolerance law came into force probably reflects enhanced police activity and more enthusiasm to apprehend and charge individuals for this offence. Illicit drugs, particularly amphetamine and cannabis, and poly-drug use were predominant compared with use of scheduled prescription drugs. The typical DUID offender in Sweden abuses central stimulants, particularly amphetamine, and has probably done so over many years. Options for treating offenders for their underlying substance abuse problem should be considered instead of the more conventional penalties for drug-impaired driving.