Antti O. Impinen

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.

Poly-drug findings in drugged driving cases during 1977–2007

Background: Driving under the influence of drugs (DUID) is an increasing public health and traffic safety related problem. We examined the poly-drug findings and their trends among all apprehended DUID offenders in Finland. Methods: A register data from 1977 to 2007 was analysed. The data included a total of 31,963 suspected DUID cases with a positive finding for an illicit/licit drug impairing driving performance. Blood and/or urine specimens were analysed in one central laboratory. Results: Poly-drug findings were common among suspected DUID cases during the entire study period. Seventy-seven per cent of the specimens had a finding from two or more substance groups. Benzodiazepines with alcohol (20% of poly-drug cases) and amphetamines with benzodiazepines (18%) were the most frequently found combinations. Benzodiazepines were present in the five most frequent combinations. The proportion of cases including drugs only increased more rapidly than the proportion of cases including a combination of drugs and alcohol during the last three decades. The level of aggravated drink-driving limit in Finland (BAC>1.2‰ ) was exceeded in 44% of the cases including alcohol. Conclusion: In addition to amphetamines, benzodiazepines formed a major concern among suspected DUID cases. The large proportion of poly-drug findings may indicate extensive substance abuse among DUID offenders.

Mortality and Causes of Death among Drugged Drivers

Background Studying drugged drivers gives complementary information about mortality of drug users, which mainly has been studied among opioid abusers. The aim of this study was to analyse mortality rates and causes of death among drivers under the influence of drugs (DUID) in Finland and compare them with the general Finnish population during 1993–2006. Methods Register data from 5832 DUID suspects apprehended by the police were studied, with a reference group (n=74 809) drawn from the general Finnish population. Deaths were traced from the National Death Register. Survival and differences in mortality hazards were estimated using Kaplan–Meier plots and Cox regression models. Results The hazard of death was higher among male (HR 9.6, CI 8.7 to 10.6) and female (HR 9.1, CI 6.4 to 12.8) DUID suspects compared to the reference population. Among male DUID suspects, cause-specific hazards were highest for poisoning/overdose, violence and suicide. 24% of DUID suspects and 8% of reference subjects were under the influence of drugs/alcohol at the time of death. Poly-drug findings indicated excess in mortality among drugged drivers. Hazard of death was higher among male DUID suspects who had findings for benzodiazepines only (HR 10.0, CI 8.4 to 11.9) or benzodiazepines with alcohol (HR 9.6, CI 8.2 to 11.2), than with findings for amphetamines (HR 4.6, CI 2.7 to 7.6). Conclusion DUID suspects had an increased risk of death in all observed causes of death. Findings for benzodiazepines indicated excessive mortality over findings for amphetamines. Preventive actions should be aimed especially at DUID subgroups using benzodiazepines.

High mortality among people suspected of drunk-driving. An 18-year register-based follow-up

OBJECTIVES The aim of this study was to examine the overall and cause-specific mortality of DUI arrestees compared to a reference population with no history of DUI and to recognize the risk factors of premature death. METHODS The data used were a register of all DUI arrestees between April 1988 and December 2006. All drivers with drug-positive samples were excluded. DUI arrestees were compared to a reference population with no previous history of DUI. Overall and cause-specific hazard ratios were calculated and risk factors were estimated. RESULTS Alcohol causes, diseases of the circulatory system and accidents constituted the most common causes of death among DUI arrestees. Suspected DUI was linked with higher mortality in every observed cause of death. The risk of death by alcohol-related or external cause was especially high. Among women DUI arrests caused sharper increase to the risk of death than increase found among male arrestees. Within the group of DUI arrestees the risk of death was affected by age, sex, marital status, education, multiple arrests as well as time and observed blood alcohol level of the arrest. Half of the suspected DUI cases and one in five of the references had alcohol as a contributing factor to death. CONCLUSIONS Arrest on suspicion of drunk-driving is an indicator for elevated risk of death. Alcohol is often related to deaths of DUI arrestees. Drunk-drivers should be efficiently guided with respect to evaluations and treatments for harmful drinking.

The Association between Social Determinants and Drunken Driving: A 15-Year Register-based Study of 81,125 Suspects

AIMS The aim of the study was to examine the association between social background and drunken driving. METHODS A Finnish register on suspected drunken driving was combined with data on social background. There were 81,125 drivers arrested for drunken driving and 86,279 references from 1993 to 2007. RESULTS A low level of education, unemployment, living alone and divorce were strongly associated with drunken driving. In addition, for persons aged 15-24 years, low parental education and income, high own income and possession of a car correlated with higher odds of drunken driving. For working-aged men and women, low income was associated with a higher risk of drunken driving. For working-aged women, also possession of a car was a risk factor. CONCLUSIONS Social factors are associated with drunken driving. In general, people with a lower social position are more prone to drive after drinking. Social differences are visible already in youth, whereas working and own income of young persons signal different risk mechanisms for youth than for working-aged people. Measures for preventing drunken driving are needed within public health policies.

Performance evaluation of the DrugWipe® 5/5+ on-site oral fluid screening device

This study presents a retrospective performance evaluation of an on-site oral fluid drug screening device DrugWipe® 5/5+ (Securetec). The results obtained by the device were compared with gas chromatography–mass spectrometry confirmation analysis results in whole blood. Data used in the comparison were based on 1,807 real cases in which the Finnish police had conducted an on-site drug test on persons suspected of driving under the influence of drugs. The present data cover only cases wherein the DrugWipe device has shown a positive result for at least one substance. The data were compiled from the databases of Alcohol and Drug Analytics Unit at the National Institute for Health and Welfare. The performance of the DrugWipe was evaluated for its relevant drug groups: amphetamines, cannabis, opiates, and cocaine. The evaluation was carried out by calculating the sensitivity, specificity, and accuracy as well as the positive and negative predictive values. These calculations were based on the classification of the results as true positives, false positives, true negatives, and false negatives. Additionally, the demographics of the cases and analytical findings in whole blood are discussed. According to this study, the DrugWipe device performed quite well in detecting amphetamines, the most frequently encountered group of illicit drugs in Finnish traffic. The performance of the cannabis, opiate, and cocaine tests was not at the same level.