The Risk of Motor Vehicle Accidents Involving Drivers With Prescriptions for Codeine or Tramadol

Development of a potential opioid misuse measure from administrative dispensing data and contrasting opioid misuse among individuals on long-term tramadol, long-term short-acting hydrocodone or long-term short-acting oxycodone therapy in Arkansas

OBJECTIVE

This study sought to: (1) construct and validate a composite potential opioid misuse score; and (2) compare potential opioid misuse among individuals prescribed long-term therapy on tramadol, short-acting hydrocodone or short-acting oxycodone.

METHODS

A retrospective cohort study was conducted using Arkansas All-Payer Claims Database (APCD; 2013-2018) linked to Arkansas Prescription Drug Monitoring Program (PDMP; 2014-2017) and state death certificate data (2013-2018). The study subjects were ambulatory, cancer-free adults with incident long-term therapy on tramadol, short-acting hydrocodone or short-acting oxycodone. The number of opioid prescribers/pharmacies, cash payment for opioid prescriptions, overlapping prescribers/pharmacies and a composite misuse score (derived from opioid prescribers/pharmacies and cash payment) were assessed in two 180 day windows as potential measures of misuse. The composite score was developed based on associations observed with opioid overdose and opioid-related injuries.

RESULTS

A total of 17,816 (tramadol), 23,660 (hydrocodone) and 4799 (oxycodone) persons were included. The composite score had modest discrimination for overdose (c-index = 0.65). In the first 180 day period, the average composite misuse scores were 1.28 (tramadol), 1.93 (hydrocodone) and 2.18 (oxycodone). Compared to long-term hydrocodone, long-term tramadol had lower misuse (IRR [95% CI]: 0.75 [0.73-0.76]), and long-term oxycodone had higher misuse (1.09 [1.07-1.11]) in adjusted analyses. Qualitatively similar associations were observed for nearly all individual component measures of misuse.

CONCLUSION

A composite measure of potential opioid misuse had modest levels of discrimination in detecting overdose. In comparison to long-term hydrocodone therapy, long-term oxycodone had higher and tramadol had lower risk of potential opioid misuse.

Opioids and the Risk of Motor Vehicle Collision: A Systematic Review

Background: Opioid analgesics are among the most commonly prescribed medications, but questions remain regarding their impact on the day-to-day functioning of patients including driving. We set out to perform a systematic review on the risk of motor vehicle collision (MVC) associated with prescription opioid exposure. Method: We searched Medline, PubMed, EMBASE, Scopus, and TRID from January 1990 to August 31, 2021 for primary studies assessing prescribed opioid use and MVCs. Results: We identified 14 observational studies that met inclusion criteria. Among those, 8 studies found an increased risk of MVC among those participants who had a concomitant opioid prescription at the time of the MVC and 3 found no significant increase of culpability of fatal MVC. The 3 studies that evaluated the presence of a dose-response relationship between the dose of opioids taken and the effects on MVC risk reported the existence of a dose-response relationship. Due to the heterogeneity of the different studies, a quantitative meta-analysis to sum evidence was deemed unfeasible. Our review supports increasing evidence on the association between motor vehicle collisions and prescribed opioids. This research would guide policies regarding driving legislation worldwide. Conclusion: Our review indicates that opioid prescriptions are likely associated with an increased risk of MVCs. Further studies are warranted to strengthen this finding, and investigate additional factors such as individual opioid medications, opioid doses and dose adjustments, and opioid tolerance for their effect on MVC risk.

When driving hurts: characterizing the experience and impact of driving with back pain

OBJECTIVES

Driving is one of the most widespread aspects of daily living to people in the United States and is an active process that requires various cognitive functions, such as attention. Chronic low back pain (CLBP) is one of the more prevalent and costly health conditions in the world, with individuals who report CLBP also reporting significant impairment across different domains of daily life both physically and cognitively. However, despite the prevalence of these two constructs, research detailing the experience of driving in pain remains largely underrepresented. This cross-sectional study sought to characterize the driving experience of people who experience CLBP, focusing on the psychological constructs related to chronic pain like pain catastrophizing, affective responses (irritability, anxiety, fear), and self-reported driving behaviors and outcomes.

METHODS

This study distributed an online questionnaire measuring pain, disability, and other psychological constructs commonly associated with CLBP like pain catastrophizing through M-turk to 307 U.S. participants with recurring CLBP and regular driving activity. Participants also answered questions regarding driving in pain, affective responses to driving in pain (i.e., irritability, anxiety, and fear), driving behaviors and violations, driving avoidance habits as a result of pain, opioid use, using pain medication while driving, and recent vehicle collisions within the past three years. Bivariate correlations were used to compare study variables, and one-way ANOVA's were used to compare means between participants with and without a collision history within the past three years.

RESULTS

Findings demonstrated significant positive associations not only between the psychological factors commonly associated with chronic pain, such as pain intensity, pain disability, pain catastrophizing, and the cognitive intrusion by pain, but also statistically significant relationships between these measures and pain intensity while driving, affective responses to driving in pain, driving violations, and driving avoidance habits. Additionally, in comparison to participants with no collision history within the past three years, participants who had been driving during a vehicle collision reported greater pain catastrophizing and cognitive intrusion by pain scores.

CONCLUSIONS

To our knowledge, the current study is the first to characterize driving experience specifically among individuals with CLBP, with attention to the relationship among key sensory, affective, and cognitive psychological metrics as well as self-reported driving history and behavior. The current findings reinforce multiple associations between pain and cognitive-affective variables that have been observed in literature outside the driving context, including pain intensity, anger, inattention, and behavioral disruption. Given that driving is a pervasive, potentially risky behavior that requires some form of cognitive focus and control, the current findings point to a continued need to examine these associations within this specific life context. We believe we have laid a groundwork for research considering the role of psychological pain variables in a driving performance. However, the nature of our analyses prevents any sort of causality from being inferred, and that future experimental research is warranted to better understand and explain these mechanisms underlying driving in pain while accounting for participant bias and subject interpretation.

Injury Prevention and long-term Outcomes following Trauma-the IPOT project: a protocol for prospective nationwide registry-based studies in Norway

INTRODUCTION

Traumatic injuries constitute a major cause of mortality and morbidity. Still, the public health burden of trauma in Norway has not been characterised using nationwide registry data. More knowledge is warranted on trauma risk factors and the long-term outcomes following trauma. The Injury Prevention and long-term Outcomes following Trauma project will establish a comprehensive research database. The Norwegian National Trauma Registry (NTR) will be merged with several data sources to pursue the following three main research topics: (1) the public health burden of trauma to society (eg, excess mortality and disability-adjusted life-years (DALYs)), (2) trauma aetiology (eg, socioeconomic factors, comorbidity and drug use) and (3) trauma survivorship (eg, survival, drug use, use of welfare benefits, work ability, education and income).

METHODS AND ANALYSIS

The NTR (n≈27 000 trauma patients, 2015-2018) will be coupled with the data from Statistics Norway, the Norwegian Patient Registry, the Cause of Death Registry, the Registry of Primary Health Care and the Norwegian Prescription Database. To quantify the public health burden, DALYs will be calculated from the NTR. To address trauma aetiology, we will conduct nested case-control studies with 10 trauma-free controls (drawn from the National Population Register) matched to each trauma case on birth year, sex and index date. Conditional logistic regression models will be used to estimate trauma risk according to relevant exposures. To address trauma survivorship, we will use cohort and matched cohort designs and time-to-event analyses to examine various post-trauma outcomes.

ETHICS AND DISSEMINATION

The project is approved by the Regional Committee for Medical Research Ethics. The project's data protection impact assessment is approved by the data protection officer. Results will be disseminated to patients, in peer-reviewed journals, at conferences and in the media.

A 'Dilute and Shoot' Liquid Chromatography-Mass Spectrometry Method for Multiclass Drug Analysis in Pre-Cut Dried Blood Spots

Drugs able to affect the auditory and nervous systems and consumed by workers to treatdifferent pathologies can represent a possible source of risk in the work environment. All the target compounds involved in the presented project show ototoxic and/or narcoleptic side effects and, for these reasons, occupational safety organizations have recognized them as potential causes of work injuries. A multiclass method for the analysis of 15 drugs among the most widespread worldwide (belonging to nine different classes including antihistamines, beta-blockers, antidepressants, Z-drugs and opioids), was developed and validated. This study describes a rapid, sensitive and effective method to analyse these substances in whole blood using tailored pre-cut dried blood spots. Detection was achieved with a triple quadrupole mass spectrometer after an easy and simple 'dilute and shoot' solubilisation followed by an UPLC separation. All the issues linked to the use of the dried blood spots and whole blood, such as haematocrit variability, volumetric evaluation and sample carrier choice were carefully studied and managed during method development. From the validation study results it emerged that this approach can be deemed successful thanks to its few pg µL-1 LOQs, good linear intervals, absolute recoveries of no less than 75%, an almost negligible matrix effect and accuracy and precision in line with the European and American guidelines for validation. All the obtained goals have been specifically pursued in order to encourage method diffusion as a primary prevention intervention, even in small private workplaces.

Opioid Use and Driving Performance

INTRODUCTION

The USA is in an opioid epidemic, with an increased number of individuals taking psychoactive drugs while executing the tasks of everyday life, including operating a motor vehicle. The pharmacology of opioids has been widely studied, but the effects of opioids on psychomotor function, driving performance, and the risk of motor vehicle collision remain less clear. Clinicians are faced with the challenge of controlling patient pain while also reconciling conflicting messages from the literature about how safe it is for their patients taking opioids to engage in potentially dangerous routine tasks.

DISCUSSION

This review assesses the current literature regarding opioids as they relate to neurocognitive function, driving performance, and accident risk. Manuscripts are categorized by study context and subject matter: controlled experimental administration, illicit use, prescription use, retrospective forensic toxicology, and polydrug consumption.

CONCLUSION

Illicit use, initiation of therapy, and opioid use in combination with other psychoactive medications are contexts most clearly associated with impairment of driving-related functions and/or operation of a motor vehicle. Clinicians should counsel patients on the risk of impairment when initiating therapy, when co-prescribing opioids and other psychoactive drugs, or when a patient is suspected of having an opioid use disorder.

Factors associated with serious vehicular accidents: A cross-sectional study in hospital emergency rooms

AIMS

Pictograms on medicine boxes warn of potential drug-related driving hazard; we studied their association with serious accidents.

METHODS

Prospective study in emergency departments of the hospitals in Bordeaux and Périgueux (France), of drivers with serious (admitted at least 24 hours) or nonserious vehicular accidents. Minors, passengers, pedestrians or subjects incapable of answering an interview were excluded. Interviews ascertained driver and accident characteristics, use of drugs with or without pictograms, use of alcohol and abuse substances, sleepiness, distractions, and mind wandering at the time of the accident, RESULTS: Between 18 October 2016 and 26 December 2018, 1200 of the 6212 drivers admitted to the hospital emergency rooms, 741 nonserious, 459 serious, were interviewed. Serious accidents were associated with male sex (odds ratio 1.89, 95% confidence interval [1.36-2.64]), age above 60 years (3.64 [2.21-6.00]), driving on local roads (3.34 [2.34-4.76]), driving a motorcycle (3.39 [2.29-5.00]), having drunk alcohol within 6 hours (2.89 [1.85-4.51]) and using a drug with a pictogram during the 24 hours previous to the accident (1.57 [1.06-2.32]). From 207 police reports, 101 drivers were not responsible, and 106 were responsible, associated with age below 40 years, driving in overcast or rainy weather (2.62 [1.29-5.33]), on local roads (3.89 [1.90-7.95]), and use of at least 1 pictogram drug in the previous week (3.12 [1.31-7.41]).

CONCLUSION

The known risks of alcohol and pictogram drugs, of riding motorcycles and using local roads were confirmed. As measured, behavioural sleepiness did not predict accidents.

Prescription opioids, alcohol and fatal motor vehicle crashes: a population-based case-control study

Background

The prevalence of prescription opioid use among drivers has increased markedly in the past two decades. The purpose of this study is to assess the associations of prescription opioid use and alcohol use with the risk of fatal crash involvement in US drivers.

Methods

We performed a population-based case-control study using toxicological testing data from two national data systems. Cases (n = 3606) were drivers involved in fatal motor vehicle crashes selected from the Fatality Analysis Reporting System and controls (n = 15,600) were drivers participating in the 2007 and 2013 National Roadside Surveys of Alcohol and Drug Use by Drivers. Multivariable logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs) of fatal crash involvement associated with prescription opioid use with and without the presence of alcohol.

Results

Overall, cases were significantly more likely than controls to test positive for prescription opioids (5.0% vs. 3.7%, p < 0.001), alcohol (56.2% vs. 7.1%, p < 0.0001), and both substances (2.2% vs. 0.2%, p < 0.001). Relative to drivers testing negative for prescription opioids and alcohol, the adjusted ORs of fatal crash involvement were 1.72 (95% CI: 1.37, 2.17) for those testing positive for prescription opioids and negative for alcohol, 17.92 (95% CI: 16.19, 19.84) for those testing positive for alcohol and negative for prescription opioids, and 21.89 (95% CI: 14.38, 33.32) for those testing positive for both substances. The interaction effect on fatal crash risk of prescription opioid use and alcohol use was not statistically significant on either additive or multiplicative scale.

Conclusions

Prescription opioid use is associated with a significantly increased risk of fatal crash involvement independently of alcohol use. Concurrent use of prescription opioids and alcohol is associated with a 21-fold increased risk of fatal crash involvement.

Characterizing the Interrelationships of Prescription Opioid and Benzodiazepine Drugs With Worker Health and Workplace Hazards

OBJECTIVE

Prescription opioid and benzodiazepine drug use, which has risen significantly, can affect worker health. Exploration of the scientific literature assessed (1) interrelationships of such drug use, occupational risk factors, and illness and injury, and (2) occupational and personal risk factor combinations that can affect their use.

METHODS

The scientific literature from 2000 to 2015 was searched to determine any interrelationships.

RESULTS

Evidence for eight conceptual models emerged based on the search yield of 133 articles. These models summarize interrelationships among prescription opioid and benzodiazepine use with occupational injury and illness. Factors associated with the use of these drugs included fatigue, impaired cognition, falls, motor vehicle crashes, and the use of multiple providers.

CONCLUSION

Prescription opioid and benzodiazepine drugs may be both a personal risk factor for work-related injury and a consequence of workplace exposures.

The impact of therapeutic opioid agonists on driving-related psychomotor skills assessed by a driving simulator or an on-road driving task: A systematic review

BACKGROUND

Driving cessation is associated with poor health-related outcomes. People with chronic diseases are often prescribed long-term opioid agonists that have the potential to impair driving. Studies evaluating the impact of opioids on driving-related psychomotor skills report contradictory results likely due to heterogeneous designs, assessment tools and study populations. A better understanding of the effects of regular therapeutic opioid agonists on driving can help to inform the balance between individual's independence and community safety.

AIM

To identify the literature assessing the impact of regular therapeutic opioid agonists on driving-related psychomotor skills for people with chronic pain or chronic breathlessness.

DESIGN

Systematic review reported in accordance with the Preferred Reporting Items for Systematic Review and Meta-analysis statement; PROSPERO Registration CRD42017055909.

DATA SOURCES

Six electronic databases and grey literature were systematically searched up to January, 2017. Inclusion criteria were as follows: (1) empirical studies reporting data on driving simulation, on-the-road driving tasks or driving outcomes; (2) people with chronic pain or chronic breathlessness; and (3) taking regular therapeutic opioid agonists. Critical appraisal used the National Institutes of Health's quality assessment tools.

RESULTS

From 3809 records screened, three studies matched the inclusion criteria. All reported data on people with chronic non-malignant pain. No significant impact of regular therapeutic opioid agonists on people's driving-related psychomotor skills was reported. One study reported more intense pain significantly worsened driving performance.

CONCLUSION

This systematic review does not identify impaired simulated driving performance when people take regular therapeutic opioid agonists for symptom control, although more prospective studies are needed.

Characterization of drug and alcohol use among senior drivers fatally injured in U.S. motor vehicle collisions, 2008-2012

OBJECTIVE

Adults 65 years of age and older comprise the fastest growing demographic in the United States. As substance use is projected to increase in this population, there is concern that more seniors will drive under the influence of impairing drugs. The purpose of this analysis was to characterize the drug and alcohol usage among senior drivers fatally injured (FI) in traffic collisions.

METHODS

Data from the Fatality Analysis Reporting System were analyzed from 2008 to 2012. Commonly used classes and specific drugs were explored. Rates of drug use, multiple drugs, concomitant drug and alcohol use, and alcohol use alone were generated using Poisson regression with robust error variance estimation. Rates were compared to a reference population of FI middle-aged drivers (30 to 50 years old) using rate ratios.

RESULTS

Drug use among FI senior drivers occurred in 20.0% of those tested. Among drug-positive FI senior drivers, narcotics and depressants were frequent. The prevalence of testing positive for any drug, multiple drugs, combined drug and alcohol, and alcohol use alone among FI seniors were 47% less (relative risk [RR] = 0.53, 95% confidence interval [CI], 0.47, 0.62), 59% less (RR = 0.41, 95% CI, 0.34, 0.51), 87% less (RR = 0.13, 95% CI, 0.09, 0.19), and 77% less (RR = 0.23, 95% CI, 0.19, 0.28), respectively, compared to FI middle-aged drivers.

CONCLUSIONS

Though overall drug use is less common among FI senior drivers relative to FI middle-aged drivers, driving under the influence of drugs may be a relevant traffic safety concern in a portion of this population.

Medication use and the risk of motor vehicle collisions among licensed drivers: A systematic review

OBJECTIVES

Driving under the influence of prescription and over-the-counter medication is a growing public health concern. A systematic review of the literature was performed to investigate which specific medications were associated with increased risk of motor vehicle collision (MVC).

METHODS

The a priori inclusion criteria were: (1) studies published from English-language sources on or after January 1, 1960, (2) licensed drivers 15 years of age and older, (3) peer-reviewed publications, master's theses, doctoral dissertations, and conference papers, (4) studies limited to randomized control trials, cohort studies, case-control studies, or case-control type studies (5) outcome measure reported for at least one specific medication, (6) outcome measure reported as the odds or risk of a motor vehicle collision. Fourteen databases were examined along with hand-searching. Independent, dual selection of studies and data abstraction was performed.

RESULTS

Fifty-three medications were investigated by 27 studies included in the review. Fifteen (28.3%) were associated with an increased risk of MVC. These included Buprenorphine, Codeine, Dihydrocodeine, Methadone, Tramadol, Levocitirizine, Diazepam, Flunitrazepam, Flurazepam, Lorazepam, Temazepam, Triazolam, Carisoprodol, Zolpidem, and Zopiclone.

CONCLUSIONS

Several medications were associated with an increased risk of MVC and decreased driving ability. The associations between specific medication use and the increased risk of MVC and/or affected driving ability are complex. Future research opportunities are plentiful and worthy of such investigation.

New opioid analgesic use and the risk of injurious single-vehicle crashes in drivers aged 50-80 years: A population-based matched case-control study

BACKGROUND

the increasing trend in opioid analgesic use among older drivers has raised concerns about their risk of being involved in car crashes.

AIM

to investigate if older drivers who started using opioid analgesics have a higher probability of being involved in injurious crashes.

METHODS

population-based matched case-control study. Data from population registers were merged using a personal identity number. Cases were drivers aged 50-80 years responsible for a single vehicle crash between 01.07.05 and 31.12.09 that led to at least one injured passenger (n = 4,445). Four controls were randomly matched to each case by sex, birth month/year, and residence area from persons holding a valid driving license who did not crash during the study period. New use was defined as at least one dispensation within 1-30 days prior to the crash, but none within the previous 31-180 days; frequent use when ≥3 dispensations were given within 0-180 days, with at least one within 31-180 days. Individuals using 1-2 non-opioid analgesic medications were used as reference category. Conditional logistic regression was used to estimate odds ratios (OR; 95% CI) adjusting for benzodiazepine use, co-morbidity, civil status and occupation.

RESULTS

adjusted odds for new use were two-fold that of drivers using 1-2 non-opioid analgesics medications (2.0; 1.6-2.5). For frequent use, adjusted odds were also increased regardless of number of dispensations (3-4 = 1.7; 1.3-2.1, 5-6 = 1.6; 1.2-2.3, and ≥7 = 1.7; 1.3-2.1).

CONCLUSION

new, but also frequent opioid analgesic use, resulted in an increased probability of single vehicle crashes. While more epidemiologic evidence is needed, patients could be advised to refrain from driving when using opioid analgesics.

The role of surfactants in the formulation of elastic liposomal gels containing a synthetic opioid analgesic

Transdermal drug delivery systems have made significant contributions to the medical community, but have yet to completely substitute oral or parenteral delivery. Recently, various strategies have been used to augment the transdermal delivery of therapeutics. Primarily, they include iontophoresis, electrophoresis, sonophoresis, chemical permeation enhancers, microneedles, and vesicular systems. Among these strategies, elastic liposomes appear promising. Elastic vesicle scaffolds have been developed and evaluated as novel topical and transdermal delivery systems, with an infrastructure consisting of hydrophobic and hydrophilic moieties together, and as a result, such scaffolds can accommodate drug molecules with a wide range of solubility. High deformability of these vesicles provides for better penetration of intact vesicles. This system is much more efficient at delivering low- and high-molecular-weight drugs to the skin in terms of quantity and depth. In this work, elastic liposomes of Tramadol HCl were prepared using a solvent evaporation method with different surfactants and were characterized using microscopy, and particle size, shape, drug content, ex vivo release, and zeta potential were also calculated. The prepared elastic liposomes were found to be in the range of 152.4 nm with a zeta potential of −22.4 mV; the entrapment efficiencies of the selected formulation was found to be 79.71%±0.27%. All formulations in the form of a gel were evaluated for physicochemical properties and were found to be homogeneous with no grittiness, and the pH of all formulations was found to be neutral. The optimized selected elastic liposomal formulation followed the Higuchi equation and Fickian diffusion and released the drug for a period of 24 hours. The overall results provide much promise for the continued investigation of deformable vesicles as transdermal drug carriers.

Medication use and the risk of motor vehicle collision in West Virginia drivers 65 years of age and older: a case-crossover study

Background

The current generation of older adults reports a higher lifetime prevalence of prescription, over-the-counter, and recreational drug use. The purpose of this analysis is to characterize the drug usage and determine the risk of motor vehicle collision associated with individual medications in a population of drivers ≥65 years.

Methods

A case-crossover study was conducted at West Virginia University Healthcare’s facilities using data obtained from the electronic health records (n = 611) of drivers ≥65 years admitted for medical treatment following a motor vehicle collision which occurred between Jan. 1, 2009 and June 30, 2014. Patients’ medication usage 14 days before collision were matched and compared to their medication usage during four control periods prior to collision. Odds ratios were then calculated for the most prevalent individual medications and pharmaceutical sub-classes using conditional logistic regression.

Results

Analgesic, cardiovascular and gastrointestinal medicines were common. Few drivers tested positive for either licit or illicit drugs. Of those testing positive for drugs, benzodiazepines and opiates were prevalent. Drivers consuming Tramadol (adjusted OR 11.41; 95 % CI 1.27, 102.15) were at a significantly increased risk of motor vehicle collision.

Conclusions

Older adult drivers who have a prescription for this medication may need to be aware of the potential risk. Further research is necessary in a larger, more nationally representative population.

Examining the impact of opioid analgesics on crash responsibility in truck drivers involved in fatal crashes

INTRODUCTION

Commercial motor vehicle (CMV) drivers, particularly drivers of large trucks continue to be a population of concern regarding traffic safety despite the reduction in large truck crash rates over the past decade. Medication and drug use while driving is one important risk factor for large truck crashes. Work-related exposures, such as vibration, manual handling and poor ergonomics contribute to an increased risk for injuries and chronic conditions and are common reasons for opioid analgesic (OA) use by CMV truck drivers. The objectives of this study were to examine the role of OA use in CMV truck drivers involved in fatal crashes by: (a) generating prevalence estimates of OA use; (b) documenting the relationship between OA use and crash responsibility.

METHODS

Case-control study using logistic regression to compare Fatality Analysis Reporting System (1993-2008) record of one or more crash-related unsafe driver actions (UDAs--a proxy measure of responsibility) between drivers with a positive drug test and drivers with a negative drug test for OA, controlling for age, other drug use, and driving history.

RESULTS

The annual prevalence of OA use among all CMV drivers of large trucks involved in fatal crashes did not exceed 0.46% for any year in the study period and mostly ranged between 0.1 and 0.2%. Male truck drivers using OA had greater odds of committing an UDA (OR: 2.80; 95% CI: 1.64; 4.81). Middle-aged users had greater odds than younger or older users.

CONCLUSION

The results of our study indicate that the presence of OAs is associated with greater odds of committing an UDA. This association may have implications for the commercial transport industry and traffic safety. However, the limited prevalence of OA use is encouraging and further research is needed to address the limitations of the study.

Risk of road accident associated with the use of drugs: a systematic review and meta-analysis of evidence from epidemiological studies

This paper is a corrigendum to a previously published paper where errors were detected. The errors have been corrected in this paper. The paper is otherwise identical to the previously published paper. A systematic review and meta-analysis of studies that have assessed the risk of accident associated with the use of drugs when driving is presented. The meta-analysis included 66 studies containing a total of 264 estimates of the effects on accident risk of using illicit or prescribed drugs when driving. Summary estimates of the odds ratio of accident involvement are presented for amphetamines, analgesics, anti-asthmatics, anti-depressives, anti-histamines, benzodiazepines, cannabis, cocaine, opiates, penicillin and zopiclone (a sleeping pill). For most of the drugs, small or moderate increases in accident risk associated with the use of the drugs were found. Information about whether the drugs were actually used while driving and about the doses used was often imprecise. Most studies that have evaluated the presence of a dose-response relationship between the dose of drugs taken and the effects on accident risk confirm the existence of a dose-response relationship. Use of drugs while driving tends to have a larger effect on the risk of fatal and serious injury accidents than on the risk of less serious accidents (usually property-damage-only accidents). The quality of the studies that have assessed risk varied greatly. There was a tendency for the estimated effects of drug use on accident risk to be smaller in well-controlled studies than in poorly controlled studies. Evidence of publication bias was found for some drugs. The associations found cannot be interpreted as causal relationships, principally because most studies do not control very well for potentially confounding factors.

Analgesics and road traffic crashes in senior drivers: an epidemiological review and explorative meta-analysis on opioids

AIM

To assess the epidemiological evidence associating the use of analgesics with the occurrence of road traffic crashes in senior drivers including a meta-analysis with specific focus on opioids.

METHODS

Systematic literature review of articles published between 1991 and 2012 retrieved from major databases using relevant key words. Eligible articles were fully reviewed and the main characteristics and results summarized. The methodological quality was assessed using the Newcastle-Ottawa Scale. Heterogeneity tests and forest and funnel plots were used as part of the meta-analysis on opioids.

RESULTS

From the potentially eligible articles, nine were selected (4 case-control, 1 case-crossover, and 4 cohort studies) of which four were of medium and five of high quality; seven investigated opioids and four non-steroidal anti-inflammatory drugs. Crash involvement (n=7) rather than responsibility (n=2) was investigated. Age and sex were the most common covariates adjusted for. Both opioids and non-steroidal anti-inflammatory drugs showed mixed results including differences across estimates between and within studies. A marginal positive effect was observed in the pooled analyses on opioids (n=6, OR 1.20; 95% CI 1.08-1.32).

CONCLUSIONS

The evidence is unconvincing in terms of number of studies, control of major confounders, and consistency of the results. The effect seen for opioids can be attributed to the lack of adjustment of key confounders such as concomitant illness or the consumption of alcohol or other psychoactive medications. There is a need for more efficient designs like larger population-based retrospective cohorts and nested case-control or case-crossover studies based on registers of high quality allowing adjustment for these factors and for the selection of unequivocal outcomes (e.g. drivers' responsibility) to produce more persuasive empirical evidence.

Effects of three therapeutic doses of codeine/paracetamol on driving performance, a psychomotor vigilance test, and subjective feelings

RATIONALE

Some recent pharmacoepidemiological studies revealed an elevated risk of driving accidents after opioid analgesics uses. Among analgesics, codeine is often associated with paracetamol in numerous pharmaceutical specialties.

OBJECTIVES

The objective of this study was to evaluate the dose-effect relationship of three usual therapeutic doses of codeine/paracetamol on driving ability, psychomotor performance, subjective alertness, in link with blood concentrations in healthy young volunteers.

METHODS

Driving performance, responses to psychomotor vigilance tests, and scales reflecting alertness were evaluated during the morning after drug intake in a double-blind, randomized, placebo-controlled study. Sixteen healthy volunteers (23.4 ± 2.7 years old, 8 men and 8 women) participated in this balanced, cross-over study. Three doses of codeine/paracetamol (20/400, 40/800, 60/1200 mg) were evaluated against placebo. Two blood samples were collected, 1 and 4 h after drug intake. In serum, codeine and morphine concentrations were determined in serum using high-performance liquid chromatography electrospray ionization-tandem mass spectrometry, and paracetamol concentrations using fluorescence polarization immunoassay.

RESULTS

Driving and psychomotor performance were not affected by any of the three codeine/paracetamol doses. However, significant, though modest, correlations were observed between the driving parameters and both morphine and codeine blood concentrations.

CONCLUSIONS

This study did not reveal any significant impairment in performance due to the three therapeutic doses used in healthy young volunteers. However, the relationships between drug blood concentration and behavioral measures suggest that an inter-subject variability in blood concentration may influence the power of the observed drug effect.

An increased risk of motor vehicle accidents after prescription of methadone

AIMS

To investigate whether exposure to methadone affects the risk of motor vehicle accident with personal injury.

DESIGN

Cohort study linking three Norwegian administrative registries using unique person identifiers.

SETTING

Information was retrieved from the Norwegian Prescription Database on any prescriptions ever received by the individuals for methadone and all prescriptions for benzodiazepines. The Norwegian Road Accident Registry provided information about motor vehicle accidents involving personal injuries on Norwegian roads. The Central Population Registry provided demographic information on all residents in Norway.

PARTICIPANTS

All Norwegian adults aged 18-69 years were observed for 2.5 years.

MEASUREMENTS

Standardized incidence ratio (SIR) was calculated by comparing the incidence of traffic accidents with personal injuries in patients exposed to methadone with the incidence in those not exposed.

FINDINGS

During the 4626 person-years observed in patients exposed to methadone, there were 26 motor vehicle accidents. There were very few accidents among the females who received methadone and they had no increased risk of being involved in motor vehicle accidents (SIR 1.1; 95% CI 0.2-3.1). We observed an increased risk of involvement in accidents among males (SIR 2.4; 95% CI 1.5-3.6). This figure did not change significantly when exposure to benzodiazepines was excluded.

CONCLUSIONS

Men exposed to methadone appear to have an increased risk of being involved in motor vehicle accidents involving personal injuries. This increased risk could not be explained by exposure of benzodiazepines.

Risk of road traffic accidents in patients discharged following treatment for psychotropic drug overdose: a self-controlled case series study in Australia

BACKGROUND

Use of psychotropic drugs is known to impair driving and increase the risk of road traffic accidents. They are also the most common drugs taken in overdose in hospital-treated episodes of self-poisoning. Most patients who take psychotropic drug overdoses are discharged within 48 hours, while they still have possible subclinical drug effects.

OBJECTIVE

Using a self-controlled case series design, we aimed to determine whether patients with psychotropic drug overdose are at a higher risk of a traffic accident in the period following discharge compared with a control period not associated with hospital-treated drug overdose.

METHODOLOGY

Using the New South Wales (NSW) Admitted Patient Data Collection (APDC) as the primary source, we retrieved 40 845 hospital separation records dated between 1 July 2000 and 30 June 2008 (8 years) in patients aged 18-80 years admitted to a hospital in NSW following an intentional self-poisoning with a psychotropic drug (coded X61 or X62 as the International Classification of Diseases, 10th Edition, [ICD-10] external cause of injury). Of these, 33459 hospital separations (i.e. discharges, transfers and deaths) involving 24 284 patients were considered eligible as the patients were discharged directly into the community where they could have driven a motor vehicle. We selected three separate post-admission periods (3 days, 1 week and 4 weeks), subtracted the number of inpatient days from each and calculated three separate post-discharge periods (immediate, intermediate and extended, respectively) for each episode of overdose. The control period was the duration of the study period where the individual was aged 18 years or older, excluding the total person-days in the post-discharge period/s and the index inpatient period/s. The APDC dataset was linked to the NSW Roads and Traffic Authority CrashLink dataset to identify any accidents in which each patient was involved as a motor-vehicle driver during the follow-up period. Incidence rate ratio (IRR) for matched post-discharge and control periods was found using random effects Poisson regression.

RESULTS

Seventy-two percent of the subjects were discharged within 2 days following their admission with overdose. Compared with the corresponding control periods the risk of a traffic accident was 3.5 times higher (IRR = 3.49; 95% CI 1.66, 7.33; p = 0.001) during the immediate, 1.9 times higher (IRR = 1.88; 95% CI 1.09, 3.25; p = 0.023) during the intermediate and 1.6 times higher (IRR = 1.65; 95% CI 1.27, 2.15; p = 0.0002) during the extended post-discharge period.

CONCLUSIONS

Self-poisoning with psychotropic drugs is associated with a markedly increased risk of a traffic accident during the first few days following discharge. These findings raise clinical and medico-legal implications concerning fitness-to-drive during this period. The risk reduces with time but remains significantly elevated after 4 weeks post-overdose. Further research is necessary to find out the factors contributing to this ongoing risk.

Genetically polymorphic OCT1: another piece in the puzzle of the variable pharmacokinetics and pharmacodynamics of the opioidergic drug tramadol

We investigated whether tramadol or its active metabolite, O-desmethyltramadol, are substrates of the organic cation transporter OCT1 and whether polymorphisms in OCT1 affect tramadol and O-desmethyltramadol pharmacokinetics. Tramadol showed high permeability through parallel artificial membrane permeability assays (PAMPAs). Tramadol uptake in HEK293 cells did not change after OCT1 overexpression, and the concentrations of tramadol in the plasma of healthy volunteers were independent of their OCT1 genotypes. In contrast, O-desmethyltramadol showed low membrane permeability, and OCT1 overexpression increased O-desmethyltramadol uptake 2.4-fold. This increase in uptake was reversed by OCT1 inhibitors and absent when loss-of-function OCT1 variants were overexpressed. Volunteers carrying loss-of-function OCT1 polymorphisms had significantly higher plasma concentrations of O-desmethyltramadol (P = 0.002, n = 41) and significantly prolonged miosis, a surrogate marker of opioidergic effects (P = 0.005, n = 24). In conclusion, polymorphisms in OCT1 influence the pharmacokinetics of O-desmethyltramadol, presumably by affecting its uptake into liver cells, and thus may modulate the efficacy of tramadol treatment.

Opioid therapy for osteoarthritis and chronic low back pain

BACKGROUND

Chronic low back pain (CLBP) and osteoarthritis (OA) of any joint are highly prevalent, occurring in > 50% of US adults aged ≥ 60 years. Opioids are prescribed more frequently for CLBP and OA than for any other noncancer pain, and the judicious use of opioids is recommended by treatment guidelines for the management of CLBP and OA pain.

OBJECTIVE

To review the appropriate role of opioid analgesics in the treatment of patients with moderate-to-severe pain due to CLBP or OA and provide recommendations for best practices when prescribing opioids.

METHODS

Articles were identified through a search of PubMed. Additional references were identified for inclusion from the reference lists of articles identified via the literature search, treatment guidelines, and Cochrane Reviews.

RESULTS

The available data suggest that opioid therapy represents a valuable treatment option in patients who do not respond to other analgesics and in whom the potential benefits of treatment outweigh the potential risks. Prescribing physicians need to perform vigilant patient screening and monitoring for signs of abuse, intervene promptly to manage or prevent adverse events and drug interactions, tailor opioid therapy to individual patients' comorbidities, and know how to switch or rotate opioids to find the best treatment option.

CONCLUSIONS

Prescribers need to understand the place of opioid therapy in a multimodal treatment program that includes patient rehabilitation to reduce pain and improve function. The analgesic benefits of opioids must be balanced against concerns about addiction and abuse, adverse events, and their potential impact on other aspects of treatment.

Benzodiazepines predict use of opioids--a follow-up study of 17,074 men and women

OBJECTIVE

To evaluate the effect of the use of benzodiazepines on prescription of opioids 4-7 years later in patients with noncancer pain.

DESIGN

A cohort of 7,991 men and 9,083 women aged 40, 45 and 60 years who reported no use of opioids in health surveys in 2000-2001 was linked to the nationwide Norwegian Prescription Database, and their prescriptions of opioids during 2004-2007 were analyzed. Moderate-high prescription frequency of opioids was defined as at least 12 prescriptions during the period January 2004-December 2007.

RESULTS

The unadjusted odds ratio for moderate-high prescription frequency of opioids for individuals who had previously used benzodiazepines was 7.7 (95% confidence interval 5.6-10.5) as compared with previous nonusers. After adjustment for musculoskeletal pain, alcohol, smoking habits, and socioeconomic variables, the odds ratio was lowered to 3.1 (2.1-4.6). The analysis of the effect of benzodiazepines and chronic pain individually and in combination suggest that use of benzodiazepines is an even stronger predictor of later opioid use than self-reported chronic pain.

CONCLUSIONS

Our study suggests that earlier use of benzodiazepines may predict repeated use of opioids. Before starting pain treatment with opioids, clinicians should take into consideration the possibility of substance abuse and mental health disorders. A central issue when prescribing opioids for chronic noncancer pain is to balance the risk of problematic use of these drugs with the benefits of pain relief.

Driving functions in a video simulator in chronic non-malignant pain patients using and not using codeine

BACKGROUND AND AIMS

A considerable number of Europeans suffer from chronic pain and are using opioids, particularly of the weak type. It is a clinical impression that many of these are driving or wish to drive a car. The aims of this study were to investigate if codeine influences driving ability in a simulator, and to examine if chronic pain per se might impair such functions.

METHODS

Twenty patients with chronic pain on long-term codeine therapy were compared to 20 chronic pain patients not using codeine in a video driving simulator test. The chronic pain patients were then compared to 20 healthy controls. The primary outcome measures were reaction time and number of missed reactions.

RESULTS

The patients using codeine 120-270 mg (mean 180 mg) daily showed the same driving skills as patients not using codeine, and the codeine level did not affect the results. This was the case both 1h after intake of a single dose of 60 mg codeine and five or more hours after the last codeine intake. The reaction times were significantly slower for the chronic pain patients, in both rural and urban driving conditions, compared to the healthy controls (difference 0.11s. and 0.12s., respectively). The chronic pain patients missed almost twice as many reactions to traffic signs. There were no difference between the groups in steering precision.

CONCLUSION

The main finding in this simulator study was that codeine does not impair driving-related abilities over and above what is associated with chronic pain per se.

Nicotine dependence predicts repeated use of prescribed opioids. Prospective population-based cohort study

PURPOSE

The aim of this study was to evaluate prospectively smoking dependence as a predictor of repeated use of prescribed opioids in non-cancer patients.

METHODS

We conducted a prospective population-based study cohort of 12,848 men and 15,894 women 30-75 years of age in health surveys in Norway during 2000-2002 with repeated opioid prescriptions (12+, during 2004-2007) recorded in the Norwegian Prescription Database as the outcome measure. Information on history of smoking and potential confounders was obtained at baseline by self-administered questionnaires. For smoking, participants were divided into categories: never; previously heavy (stopped maximum of 5 years earlier; 10+ cigarettes daily); daily not heavy (1-9 cigarettes); dependent daily smokers (10+ cigarettes), and other (previously and/or not daily). Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated by logistic regression.

RESULTS

During follow-up, 335 (1.5%) of survey participants were registered with 12+ prescriptions of opioids during the period 2004-2007. The prevalence of repeated prescription frequency of opioids was higher for men and women with a history of smoking. The adjusted OR for prescribed opioids for dependent daily smokers was 3.1 (95% CI: 2.3-4.1), for daily non-heavy smokers 1.8 (1.2-2.7), and for previous heavy smokers 1.8 (1.1-3.0), compared with never-smokers as reference.

CONCLUSIONS

Results of the study suggest that smoking dependence may predict more frequent use of opioids.