Drug use and driving behaviors among drivers with and without alcohol-related infractions.

INTRODUCTION: Brazil is one of the countries with the highest rates of alcohol-related traffic infractions, but little is known about the profile of the drivers who commit them. Identifying the characteristics of impaired drivers is essential for planning preventive actions. OBJECTIVE: To compare drug use and driving behavior profiles of drivers with and without alcohol-related infractions. METHODS: 178 drivers stopped at routine roadblocks were assessed by traffic agents who conducted standard roadblock procedures (document verification; request of a breathalyzer test [BT]). Drug use and driving behavior data were collected through semi-structured interviews. Subjects were divided into three groups: drivers who refused the BT (RDs, n = 72), drivers who tested positive on the BT (PDs, n = 34), and drivers who had committed other infractions (ODs, n = 72). RESULTS: The proportion of alcohol use in the last year was higher among RDs (100%) than in the PD and OD groups (97.1% and 72.2% respectively, p < 0.001). Lifetime prevalence of cannabis and cocaine use for the overall sample was 44.3% and 18.2%, respectively. Fewer individuals in the OD group (31.5%) reported having been stopped at roadblocks in the previous year compared to the PDs (55.9%) and RDs (48.6%, p = 0.03). However, a higher proportion of RDs reported drunk driving in the same period (87.5%; PD 69.7%; OD 26.9%; p < 0.001). CONCLUSION: Essential differences among groups were observed. RDs had a higher proportion of alcohol use and drunk driving in the previous year; drivers who fit into this particular group may be unresponsive or less responsive to social deterrence and enforcement actions.

Drug use and driving behaviors among drivers with and without alcohol-related infractions

Abstract Introduction Brazil is one of the countries with the highest rates of alcohol-related traffic infractions, but little is known about the profile of the drivers who commit them. Identifying the characteristics of impaired drivers is essential for planning preventive actions. Objective To compare drug use and driving behavior profiles of drivers with and without alcohol-related infractions. Methods 178 drivers stopped at routine roadblocks were assessed by traffic agents who conducted standard roadblock procedures (document verification; request of a breathalyzer test [BT]). Drug use and driving behavior data were collected through semi-structured interviews. Subjects were divided into three groups: drivers who refused the BT (RDs, n = 72), drivers who tested positive on the BT (PDs, n = 34), and drivers who had committed other infractions (ODs, n = 72). Results The proportion of alcohol use in the last year was higher among RDs (100%) than in the PD and OD groups (97.1% and 72.2% respectively, p < 0.001). Lifetime prevalence of cannabis and cocaine use for the overall sample was 44.3% and 18.2%, respectively. Fewer individuals in the OD group (31.5%) reported having been stopped at roadblocks in the previous year compared to the PDs (55.9%) and RDs (48.6%, p = 0.03). However, a higher proportion of RDs reported drunk driving in the same period (87.5%; PD 69.7%; OD 26.9%; p < 0.001). Conclusion Essential differences among groups were observed. RDs had a higher proportion of alcohol use and drunk driving in the previous year; drivers who fit into this particular group may be unresponsive or less responsive to social deterrence and enforcement actions.

The impact of sleep deprivation and alcohol on driving: a comparative study.

BACKGROUND: There is concern about the detrimental effects of shift-workers' increasing working hours particularly when driving sleep deprived. The approach to measuring the magnitude of driving impairment caused by sleep deprivation was by comparing it to alcohol. The study compared driving performance after 24-h of wakefulness to performance with a BrAC of just over 22 µg/100mls of breath which is equal to 50 mg of alcohol per 100mls of blood (Scottish drink-drive limit). The effectiveness of coffee as a countermeasure for driver fatigue and the association between subjective impairment and actual performance was also investigated. METHODS: A study of 30 participants (11 male and 19 female; mean age 21) was conducted. Subjects were tested under three conditions: fully rested, sleep deprived, and alcohol intoxicated - BrAC mean [SD] 25.95 µg [2.78]. Under each condition, subjects were tested before and after coffee ingestion. This involved driving simulation (Lane Change Task and Reaction Test) and subjective Likert scales (Karolinska Sleepiness Scale and driver impairment scale). Outcome measures included lane tracking adaptive mean deviation, reaction time, and subjective sleepiness and impairment ratings. RESULTS: Compared to alcohol, sleep deprived mean reaction times were slower (2.86 s vs. 2.34 s) and lateral control of the vehicle was reduced (lane tracking adaptive mean deviation: 0.5 vs. 0.3). Coffee did not produce an improvement when sleep deprived, and instead, performance deteriorated. Females were less impaired following sleep deprivation than males. Following prolonged wakefulness, the correlation between subjective impairment and actual performance was significant. CONCLUSIONS: It was concluded that sleep deprivation has a greater impact on driving performance than a BrAC of 22 µg/100mls of breath, as measured by driving simulation. Coffee is not an effective countermeasure for sleep deprived driving and drivers' ability to judge this impairment is suggested to be limited.

Enhancement of unsafe behaviors in simulated moped-riding performance under the influence of low dose of alcohol.

The effects of low levels of blood alcohol concentration (BAC) on motorcyclist performance are still not fully comprehended. The great majority of the studies are, in fact, focused on car driving. So far, it is known that even BAC levels below the legal limit negatively affect riding motor skills correlated with crash rate. In the present study, we used a moped riding simulator to investigate the effects of low alcohol dosages (under the limits established in Italy, and in most European countries) on the defensive riding ability of light drinkers, particularly focusing on the degree of danger characterizing their riding performance. We recruited 24 participants through a double-blind, random distribution, balanced, cross-over design. We administered moderate amounts of alcohol to participants during two sessions of moped riding simulation. The results showed that even though BAC levels were always below (mean value: 0.03 g/dL) the limit allowed by Italian traffic law (0.05 g/dL), alcohol induced a reduction in safe riding behaviors, as indicated by the greater amount of hazardous scenes faced with dangerous riding behaviors when participants were under the influence of alcohol than when they were sober. Moreover, low BAC levels had a greater detrimental influence when a certain amount of learning had already been achieved by the participants (i.e., in the last experimental session). The results suggest that the effect of a low dose of alcohol interacts with participants' self-confidence.

Recreational cannabis use impairs driving performance in the absence of acute intoxication.

BACKGROUND: Across the nation, growing numbers of individuals are exploring the use of cannabis for medical or recreational purposes, and the proportion of cannabis-positive drivers involved in fatal crashes increased from 8 percent in 2013 to 17 percent in 2014, raising concerns about the impact of cannabis use on driving. Previous studies have demonstrated that cannabis use is associated with impaired driving performance, but thus far, research has primarily focused on the effects of acute intoxication. METHODS: The current study assessed the potential impact of cannabis use on driving performance using a customized driving simulator in non-intoxicated, heavy, recreational cannabis users and healthy controls (HCs) without a history of cannabis use. RESULTS: Overall, cannabis users demonstrated impaired driving relative to HC participants with increased accidents, speed, and lateral movement, and reduced rule-following. Interestingly, however, when cannabis users were divided into groups based on age of onset of regular cannabis use, significant driving impairment was detected and completely localized to those with early onset (onset before age 16) relative to the late onset group (onset ≥16 years old). Further, covariate analyses suggest that impulsivity had a significant impact on performance differences. CONCLUSIONS: Chronic, heavy, recreational cannabis use was associated with worse driving performance in non-intoxicated drivers, and earlier onset of use was associated with greater impairment. These results may be related to other factors associated with early exposure such as increased impulsivity.

Cortisol stress response predicts 9-year risky driving convictions in male first-time driving-while-impaired offenders.

BACKGROUND: With driving while impaired by alcohol (DWI) representing a persistent burden on global health, better understanding and prevention of recidivism following a first-time DWI conviction are needed. Progress towards these goals is challenged by the marked heterogeneity in offender characteristics and a traffic safety literature that relies on subjective self-report measures and cross-sectional study designs. The present study tested the hypothesis that an objective neurobiological marker of behavioural maladjustment, the cortisol stress response (CSR), predicts future DWI and other traffic convictions over a 9-year follow-up period. METHODS: One hundred thirty-two male first-time DWI offenders and 31 non-offender comparators were recruited and assessed at intake for their substance use, psychosocial and psychological characteristics and CSR. Traffic conviction data were obtained from provincial driving records. Survival analysis estimated the association between CSR and risk of a traffic conviction over time. RESULTS: In support of our hypothesis, blunted CSR predicted traffic convictions during the follow-up duration. This effect generalized to both DWI offenders and non-DWI drivers. While CSR was lower in DWI offenders compared to non-offenders, it did not specifically predict recidivism in DWI offenders. Modelling results indicated that blunted CSR, along with DWI offender group membership, experience seeking and drug use frequency, may demarcate a high-risk driver phenotype. CONCLUSIONS: CSR is a neurobiological marker of a driver phenotype with elevated generalized driving risk. For drivers with characteristics consistent with this phenotype, expanding the focus of intervention to address multiple forms of risky driving may be necessary to curb their overall threat to traffic safety.

Neurocognitive and behavioral markers in DUI recidivists.

Objective: Driving under the influence (DUI) of alcohol recidivism may be a risk-taking behavior motivated by a change in decision-making capacity. Decision-making capacity has been investigated by event-related potentials (ERPs) acquisition and specifically by analyzing feedback-related negativity (FRN) reflecting the activity of medial prefrontal cortex. Thus, the aim of our study was to test the role of FRN as a possible neurophysiological marker of underestimation of risk associated with DUI recidivism to provide novel insights into the influence of neurocognitive aspects of driving ability.Methods: The research was structured as a case-control study. The total cohort (30 Italian male subjects) was divided into 2 groups, according to positive or negative history of DUI recidivism. The protocol included informed consent collection, medical history and clinical examination, ERP registration, and sensation-seeking scale administration. ERPs were acquired during a gambling task. The data were analyzed with 2 analysis of variance (ANOVA) repeated measures. Statistical analyses were conducted using R to test the participants' risk behaviors. A multivariate ANOVA was run to compare the personality traits of the groups. ANOVAs and planned comparisons were performed with StatSoft software.Results: FRN amplitude analyses showed that the interaction Reward Magnitude × Valence (large vs. small × gains vs. losses) was significant for recidivists (F(1,13) = 11.75, P < .01) but not for controls (F(1,14) = 0.04, P = .84). The results of the logistic generalized linear models analysis showed that the 2 groups differed in risk-taking behavior (z = -3.65; P < .001) with an average of 70 risky choices for recidivists and 63 for controls. Both groups were homogeneous for personality traits.Conclusions: The FRN and gambling task results suggest that DUI recidivists seemed attracted by the prospect of a large reward and appeared unable to recognize small losses read as wins These results, if confirmed in a larger sample, could indicate the usefulness of ERP analysis in clinical and forensic evaluation of DUI subjects.

Classification of Fatigued and Drunk Driving Based on Decision Tree Methods: A Simulator Study.

It is a commonly known fact that both alcohol and fatigue impair driving performance. Therefore, the identification of fatigue and drinking status is very important. In this study, each of the 22 participants finished five driving tests in total. The control condition, serving as the benchmark in the five driving tests, refers to alert driving. The other four test conditions include driving with three blood alcohol content (BAC) levels (0.02%, 0.05%, and 0.08%) and driving in a fatigued state. The driving scenario included straight and curved roads. The straight roads connected the curved ones with radii of 200 m, 500 m, and 800 m with two turning directions (left and right). Driving performance indicators such as the average and standard deviation of longitudinal speed and lane position were selected to identify drunk driving and fatigued driving. In the process of identification, road geometry (straight segments, radius, and direction of curves) was also taken into account. Alert vs. abnormal and fatigued vs. drunk driving with various BAC levels were analyzed separately using the Classification and Regression Tree (CART) model, and the significance of the variables on the binary response variable was determined. The results showed that the decision tree could be used to distinguish normal driving from abnormal driving, fatigued driving, and drunk driving based on the indexes of vehicle speed and lane position at curves with different radii. The overall accuracy of classification of "alert" and "abnormal" driving was 90.9%, and that of "fatigued" and "drunk" driving was 94.4%. The accuracy was relatively low in identifying different BAC degrees. This experiment is designed to provide a reference for detecting dangerous driving states.

Driving Under the Influence: How Music Listening Affects Driving Behaviors.

Car driving is a daily activity for many individuals in modern societies. Drivers often listen to music while driving. The method presented here investigates how listening to music influences driving behaviors. A driving simulation was selected because it offers both a well-controlled environment and a good level of ecological validity. Driving behaviors were assessed through a car-following task. In practice, participants were instructed to follow a lead vehicle as they would do in real life. The lead vehicle speed changed over time requiring constant speed adjustments for the participants. The inter-vehicular time was used to assess driving behaviors. To complement the driving behaviors, the subjective mood and physiological level of arousal were also collected. As such, the results collected using this method offer insights on both the human internal state (i.e., subjective mood and physiological arousal) and driving behaviors in the car following task.

Evaluation of simulated driving in comparison to laboratory-based tests to assess the pharmacodynamics of alprazolam and alcohol.

RATIONALE: Assessment of the effects of medicines on the risks of car driving must be derived from laboratory tests, simulated driving or real on-road driving tests. Relevance of tests is determined by their sensitivity and predictive ability for the probability of accidents or damage. This cannot be determined directly, but methods should be able to at least detect the effects of a positive control in dosage known to be clearly associated with increased risk. OBJECTIVES: A driving simulator was evaluated in comparison with a battery of validated tests of CNS performance, the NeuroCart®. Alcohol in a concentration exactly at the legal limit (0.5 g L-1) and well above (1.0 g L-1) as well as alprazolam (1 mg) was used as positive control. METHODS: This was a randomised, cross-over study using a double dummy blinded design in 24 healthy study subjects (12 M, 12 F) aged 20-43 years. Alcohol was infused intravenously using a validated clamping protocol to obtain concentrations of 0.5 g L-1 and on another occasion 1.0 g L-1. Alprazolam was given orally. Driving tests and lab tests were done at regular time intervals during a study day. RESULTS: Alprazolam and alcohol significantly affected the main parameters of driving in the simulator and affected scores of safe driving and alprazolam increased the odds ratio of a virtual crash. Several laboratory measurements of psychomotor performance were affected by the reference substances as expected and correlated significantly with the driving performance. CONCLUSIONS: The driving simulator can detect effects of reference substances at levels that are known to negatively affect driving.