Drivers who tested positive for cannabis in oral fluid: a longitudinal analysis of administrative data for Spain between 2011 and 2016.

OBJECTIVES: This study aimed to assess the association between positive roadside tests for delta-9-tetrahydrocannabinol (THC) and other driving-impairing substances and THC concentrations and the age and gender of THC-positive drivers. DESIGN: This study is based on administrative data. SETTING, PARTICIPANTS AND EXPOSURES: National administrative data on drivers who tested positive in confirmation analysis of driving-impairing substances in oral fluid were assessed (2011-2016, 179 645 tests). PRIMARY AND SECONDARY OUTCOME MEASURES: Frequencies of positivity for THC, THC alone and THC plus non-THC substances (stratification by age and gender in 2016) and THC concentration were obtained. Comparisons and univariate and multivariate regression analyses were performed. RESULTS: Of the 65 244 confirmed drug-positive tests, 51 869 were positive for THC (79.5%). In 50.8% of the THC-positive tests, cocaine and amphetamines were also detected. Positivity for THC and non-THC substances predominated among drivers with low THC concentrations and represented 58.6% of those with levels lower than 25 ng/mL. The mean±SD for age was 29.6±7.7 years (year 2016, n=24 941). Men accounted for 96.3% of all THC-positive drivers. With increasing age, positivity for THC decreased (OR 0.948; 95% CI 0.945 to 0.952; p<0.0001), and positivity for THC and non-THC substances increased (OR 1.021; 95% CI 1.017 to 1.024; p<0.0001). Men were associated with higher THC concentrations (OR 1.394; 95% CI 1.188 to 1.636; p<0.0001). CONCLUSIONS: Cannabis positivity is frequent among drivers, and polysubstance use is common. Hence, focusing on younger drivers and those with low THC concentrations is encouraged. This study provides evidence on the current implementation of roadside drug testing in Spain and aims to characterise driving under the influence (DUI) of cannabis to increase the awareness of all involved to help them avoid DUI.

Opioids in oral fluid of Spanish drivers.

BACKGROUND: Driving under the influence of certain drugs is not allowed, and roadside drug testing is being considered an important tool for deterring driving under the influence of them. This study aimed to assess the presence and concentration of opioids, as well as their combined use with other drugs (laboratory confirmation after the on-road screening) in Spanish drivers between 2011 and 2016. METHODS: In Spain, mandatory roadside breath alcohol and oral fluid drug testing (screening) are carried out by the Traffic Police using Dräger Alcotest® 6810 device, and Dräger DrugTest® 5000, DrugWipe®, or Alere™ DDS®2 Mobile Test System. For positive cases in the period covered, 65,244, confirmation analysis and quantification using chromatographic techniques were performed. RESULTS: Opioids were confirmed in 8.6% of positive cases, being 7.2% positives to 6-acetylmorphine (6-AM), 6.5% to morphine, 5.4% to codeine, and 4.1% to methadone. The majority of the confirmed tests for morphine (96.5%), codeine (88.4%) and methadone (81.9) were also positive for 6-AM. The presence of other drugs, particularly cocaine and cannabis, was very common. Concentration values reached important levels. Positive results for morphine (0.1%), codeine (0.6%) or methadone (0.4%) alone were very infrequent. CONCLUSIONS: Drivers with a confirmed positive roadside test for morphine, codeine, and methadone had also consumed heroin and/or other illicit drugs, such as cocaine and/or THC, and at relevant concentrations. Improving interventions to combat the problem of driving under the influence of driving-impairing substances is a priority.

Roadside opioid testing of drivers using oral fluid: the case of a country with a zero tolerance law, Spain.

BACKGROUND: Opioids can impair psychomotor performance, and driving under the influence of opioids is associated with an increased risk of accidents. The goals of this study were i) to determine the prevalence of opioids (heroin, morphine, codeine, methadone and tramadol) in Spanish drivers and ii) to explore the presence of opioids, more specifically whether they are used alone or in combination with other drugs. METHODS: The 2008/9 DRUID database regarding Spain was used, which provided information on 3302 drivers. All drivers included in the study provided a saliva sample and mass-chromatographic analyses were carried out in all cases. To determine the prevalence, the sample was weighted according to traffic intensity. In the case of opioid use combinations, the sample was not weighted. The detection limit for each substance was considered a positive result. RESULTS: The prevalence of opioids in Spanish drivers was 1.8% (95% CI, 1.4-2.3). Polydrug detection was common (56.2%): of these, in two out of three cases, two opioids were detected and cocaine was also detected in 86% of the cases. The concentration (median [Q1-Q3] ng/ml) of the substances was low: methadone 1.71 [0.10-15.30], codeine 40.55 [2.10-120.77], 6-acetylmorphine 5.71 [1.53-84.05], and morphine 37.40 [2.84-200.00]. Morphine was always detected with 6-acetylmorphine (heroin use). CONCLUSIONS: Driving under the influence of opioids is relatively infrequent, but polydrug use is common. Our study shows that 6 out of 10 drivers with methadone in their OF (likely in methadone maintenance programs) are using other substances. This should be taken into account by health professionals in order to properly inform patients about the added risks of mixing substances when driving.

Prevalence of psychoactive substances, alcohol, illicit drugs, and medicines, in Spanish drivers: a roadside study.

Following population, geographic, road type and time criteria, Spain has carried out random, roadside controls of 3302 representative sample of Spanish drivers, including saliva analysis for 24 psychoactive substances and alcohol breath tests. The 81.4% of the drivers were male, with an average age of 34.8±11.8 (mean±SD). The 17% of the drivers were found to be positive to any of the substances analysed. The 6.6% of the drivers found positive to alcohol (>0.05 mg/l in breath), 11% were found positive to any illicit drug, and 2% were positive to one of the medicines analysed. Some drivers were positive in more than one substance. The most common illicit drugs among Spanish drivers were cannabis (7.7%), or cocaine (3.5%), either alone or combined with other substances. The most prevalent medicines were the benzodiazepines (1.6%). As a tendency, higher figures for positive cases were observed among males than in females (being statistically significant the differences for alcohol, cannabis and cocaine). Alcohol and cocaine positive cases were more frequently found among drivers of urban roads. Alcohol positive cases (alone, >0.05 mg/l), were more likely found as age increase (OR=1.02), those driving in urban roads (OR=2.13), and driving at any period than weekdays, while alcohol+drugs cases were more likely found among males (OR=2.819), those driving on urban road (OR=2.17) and driving at night periods. Finding a medicines positive case was more likely as elder the driver was (OR=1.05). There have been differences in the prevalence of positive cases of alcohol, cannabis and cocaine, in relation to the period of the week: in three cases the highest prevalence seen in night time. This study shows the high prevalence of psychoactive substances and alcohol in Spanish drivers, mainly illicit drugs (cannabis). This question requires a response from the authorities and from society, with an integral and multi-disciplinary approach that can heighten the population's awareness of the risks of driving under the influence of certain substances.