A comparative study of the effects of carbamazepine and the NMDA receptor antagonist remacemide on road tracking and car-following performance in actual traffic

Impact of antiepileptic drugs on simulated driving in patients with epilepsy

OBJECTIVE

Results of observational investigations have demonstrated that the risk of a traffic accident is independent of use of AEDs. However, no reports of driving tests conducted with patients administered AEDs have been presented. This study examined this scenario in a simulated driving setting.

METHODS

Driving performance of 43 patients with epilepsy (PWE) and prescribed an AED, who were licensed to drive and drove regularly (subject group), was assessed, with the results compared to 40 age- and gender-matched healthy volunteers (control group). Daily driving skills associated with a traffic accident were examined using two different tests provided by a driving simulator software package, road-tracking and car-following. Standard deviation of lateral position (SDLP) and distance coefficient of variation (DCV) were determined as primary and exploratory outcomes, respectively.

RESULTS

There was no statistically significant difference for primary outcome shown by SDLP between the subject and control groups (p = 0.906), nor for exploratory outcome shown by DCV (p = 0.063). Multiple regression analysis revealed that age (ß=0.967, p = 0.001), female gender (ß=0.469, p<0.001), and duration of driving experience (ß=-0.583, p = 0.038) were correlated with SDLP.

SIGNIFICANCE

The present results demonstrated that the driving performance of PWE taking AEDs was not different from that of healthy volunteers.

Validity and reliability of a driving simulator for evaluating the influence of medicinal drugs on driving performance

RATIONALE

Although driving simulators (DS) are receiving increasing attention due to concern over traffic accidents under the influences of drugs, few DS are recognized for their reliability and validity. Therefore, the development of an evaluation system using DS for driving performance is urgently needed.

OBJECTIVES

To investigate whether the standard deviation of lateral position (SDLP) increases with blood alcohol concentration (BAC) using a DS with reliability and calculate the SDLP threshold from the difference between BAC levels of 0 and 0.05%.

METHODS

Twenty healthy Japanese men performed the DS tasks up to 60 min in Study 1 and DS tasks twice at 1-week intervals in Study 2. Twenty-six healthy men conducted the same DS tasks under BAC level (0, 0.025, 0.05, and 0.09%) in double-blind, randomized, crossover trial in Study 3. The primary outcome was SDLP in a road-tracking test. The test-retest reliability of DS data was assessed, and the estimated difference in SDLP between BAC levels of 0 and 0.05% was calculated using a linear regression model.

RESULTS

The cumulative SDLP values at 5-min intervals were stable, and the intraclass correlation coefficient for its values was 0.93. SDLP increased with BAC in a concentration-dependent manner. The predicted ΔSDLP value for the difference between BAC levels of 0 and 0.05% was 9.23 cm. No participants dropped out because of simulator sickness.

CONCLUSIONS

The new DS used in these studies has reliability, validity, and tolerability and is considered suitable for evaluating the influence of drugs on driving performance.

Evaluation method regarding the effect of psychotropic drugs on driving performance: A literature review

Although automobile driving is necessary for many people, including patients with mental disorders, the influence of psychotropic drugs on driving performance remains unclear and requires scientific verification. Therefore, the objective of this study was to conduct a review of the literature in order to aid the development of a valid evaluation method regarding the influence of medication on driving performance. We conducted a literature search using two sets of terms on PubMed. One set was related to psychotropic drugs, and the other to driving tests. We excluded reviews and case studies and added literature found on other sites. A total of 121 relevant reports were found. The experiments were roughly divided into on-the-road tests (ORT) and driving simulators (DS). Although highway driving tests in ORT are most often used to evaluate driving performance, DS are becoming increasingly common because of their safety and low cost. The validity of evaluation methods for alcohol should be verified; however, we found that there were few validated tests, especially for DS. The scenarios and measurement indices of each DS were different, which makes it difficult to compare the results of DS studies directly. No evaluation indices, except for SD of lateral position, were sufficiently validated. Although highway ORT are the gold standard, DS were shown to have an increasing role in evaluating driving performance. The reliability of DS needs to be established, as does their validation with alcohol in order to accumulate more high-quality evidence.

Driving performance under alcohol in simulated representative driving tasks: an alcohol calibration study for impairments related to medicinal drugs

Comparing drug-induced driving impairments with the effects of benchmark blood alcohol concentrations (BACs) is an approved approach to determine the clinical relevance of findings for traffic safety. The present study aimed to collect alcohol calibration data to validate findings of clinical trials that were derived from a representative test course in a dynamic driving simulator. The driving performance of 24 healthy volunteers under placebo and with 0.05% and 0.08% BACs was measured in a double-blind, randomized, crossover design. Trained investigators assessed the subjects' driving performance and registered their driving errors. Various driving parameters that were recorded during the simulation were also analyzed. Generally, the participants performed worse on the test course (P < 0.05 for the investigators' assessment) under the influence of alcohol. Consistent with the relevant literature, lane-keeping performance parameters were sensitive to the investigated BACs. There were significant differences between the alcohol and placebo conditions in most of the parameters analyzed. However, the total number of errors was the only parameter discriminating significantly between all three BAC conditions. In conclusion, data show that the present experimental setup is suitable for future psychopharmacological research. Thereby, for each drug to be investigated, we recommend to assess a profile of various parameters that address different levels of driving. On the basis of this performance profile, the total number of driving errors is recommended as the primary endpoint. However, this overall endpoint should be completed by a specifically sensitive parameter that is chosen depending on the effect known to be induced by the tested drug.

Assessing the driving performance of a person with epilepsy presurgery and postsurgery

Occupational therapists and certified driving rehabilitation specialists are uniquely skilled to assess functional abilities underlying driving performance. However, little information exists on the utility of clinical assessments to determine driving performance in people with epilepsy. This case study demonstrates how an occupational therapy evaluation battery was used to examine differences in visual and cognitive abilities and simulated driving performance before and after epilepsy surgery. Specifically, a 43-yr-old White man with right anterior lobe epilepsy underwent temporal lobectomy and had his driving-related abilities and simulated driving performance assessed pre- and postsurgery. The occupational therapy evaluation indicated improvements in executive skills, attention, and information processing speed postsurgery. Visuospatial abilities worsened after surgery, likely contributing to the modest increase in vehicle position errors on the driving simulator. Nevertheless, simulated driving performance improved after temporal lobectomy. Reductions in the number of visual scanning, lane maintenance, and speed regulation errors were recorded.

Medicinal Δ(9) -tetrahydrocannabinol (dronabinol) impairs on-the-road driving performance of occasional and heavy cannabis users but is not detected in Standard Field Sobriety Tests

AIMS

The acute and chronic effects of dronabinol [medicinal Δ(9) -tetrahydrocannabinol (THC)] on actual driving performance and the Standard Field Sobriety Test (SFST) were assessed. It was hypothesized that occasional users would be impaired on these tests and that heavy users would show less impairment due to tolerance.

DESIGN, SETTING AND PARTICIPANTS

Double-blind, placebo-controlled, randomized, three-way cross-over study. Twelve occasional and 12 heavy cannabis users (14 males/10 females) received single doses of placebo, 10 and 20 mg dronabinol.

MEASUREMENTS

Standard deviation of lateral position (SDLP; i.e. weaving) is the primary measure of road-tracking control. Time to speed adaptation (TSA) is the primary reaction-time measure in the car-following test. Percentage of impaired individuals on the SFST and subjective high on a visual analogue scale were secondary measures.

FINDINGS

Superiority tests showed that SDLP (P = 0.008) and TSA (P = 0.011) increased after dronabinol in occasional users. Equivalence tests demonstrated that dronabinol-induced increments in SDLP were bigger than impairment associated with BAC of 0.5 mg/ml in occasional and heavy users, although the magnitude of driving impairment was generally less in heavy users. The SFST did not discriminate between conditions. Levels of subjective high were comparable in occasional and heavy users.

CONCLUSIONS

Dronabinol (medicinal tetrahydrocannabinol) impairs driving performance in occasional and heavy users in a dose-dependent way, but to a lesser degree in heavy users due possibly to tolerance. The Standard Field Sobriety Test is not sensitive to clinically relevant driving impairment caused by oral tetrahydrocannabinol.

Associations between clinical tests and simulated driving performance in persons with epilepsy

People with epilepsy (PWE) may experience seizures that constitute a risk to road safety. Consequently, many states have instituted restrictions, such as being seizure-free for intervals of 3 to 12 months, before driving can be resumed. However, 30% of drivers with recurrent seizures still drive despite having a restricted license. As a result of recurrent and uncontrolled seizures, PWE may have impairments in motor, visual and cognitive abilities, as well as impaired driving performance. No studies to date have prospectively examined factors associated with driving performance in PWE. The primary objective of this study was to determine which tests, from a clinical battery, are correlated with driving errors in PWE using a simulator. The sample consisted of 16 drivers with epilepsy (mean age 44.3±12.0; 63% women) recruited from the epilepsy monitoring unit at the University of Florida. All participants completed a clinical battery of cognitive, visual and motor tests, as well as a 35-minute drive on a simulator. Significant correlations emerged between: visual acuity with visual scanning (r=.69, p<.01) and adjustment to stimuli (r=.60, p<.05); contrast sensitivity with lane maintenance (r=-.54, p>.05), vehicle position (r=-.61, p>.05) and total number of errors (r=-.72, p>.01); and useful field of view scores (subtest 2) with visual scanning (r=.57, p>.05) and vehicle position (r=.63, p>.05). Limitations and future implications are addressed. The preliminary findings suggest visual and visual-cognitive tests are associated with driving errors in a simulated driving environment.

Short-term effects of morning versus evening dose of hydroxyzine 50 mg on cognition in healthy volunteers

It is well known that the sedative properties of antihistamines can differ considerably between individual drugs. Several factors have been suggested to determine the presence, absence, and/or magnitude of sedation by antihistamines. Research has suggested that the sedative effects caused by central H1 blockade partly depend on the availability of histamine competing for the same receptor and that this competition is affected by a mechanism related to sleep. Consequently, the present study was designed to compare the effects of evening and morning doses of the first-generation antihistamine hydroxyzine on cognition. It was expected that the sedative effect of hydroxyzine would be apparent in the evening after an evening dose but would be smaller in the morning after a morning dose owing to the greater release of histamine shortly after awakening. Eighteen participants (9 females) participated in a placebo-controlled, randomized, double-blind 3-way crossover design. Performance was assessed using several psychomotor tests: that is, divided attention task, critical tracking task, stop signal task, the attention network test, and the experimental attention switch task. Results demonstrated that evening doses of hydroxyzine impaired performance on the divided attention and the attention network test. Impairment after morning doses was generally larger in magnitude and affected performance measures in all tasks. It is concluded that hydroxyzine-induced impairment at tmax is more prominent after morning doses compared with evening doses and that the present study could not present direct evidence to substantiate the hypothesis that histamine availability inversely affects the magnitude of antihistamine impairment.

Effects of oxcarbazepine and carbamazepine on driving ability: a double-blind, randomized crossover trial with healthy volunteers

RATIONALE

Carbamazepine (CBZ) is known to produce cognitive side effects being at least partly relevant for driving. In contrast to this, the cognitive effects of oxcarbazepine (OXC) are suspected to be less pronounced.

OBJECTIVE

This study aimed to test 900 mg/day OXC as compared to 600 mg/day CBZ with respect to driving.

METHODS

Driving performance of 27 healthy volunteers under subchronic treatment of OXC and CBZ was assessed in a driving simulator with a double-blind, randomized, crossover design including a baseline measurement. The test course contained a representative set of scenarios. Lane-keeping performance, driving mistakes, and eyelid closure (as a behavioral measure of sleepiness) were analyzed. In addition, subjects were asked to assess their driving performance, effort, attention, and sleepiness subjectively.

RESULTS

Both drugs had negative effects on driving as reflected in poorer lane-keeping performance, higher rate of driving mistakes, increased sleepiness, and worse subjective ratings. These effects were most obvious in monotonous situations and could be compensated in situations challenging to cognitive and motor driving skills. With respect to all considered parameters, CBZ did more often differ significantly from baseline than OXC.

CONCLUSIONS

Under both drugs, driving performance was worse than at baseline. Even though deterioration of driving performance was only slightly less pronounced under OXC than under CBZ, it might be recommended as more appropriate than CBZ for epileptic patients who need to drive a car.

The cognitive and psychomotor effects of remacemide and carbamazepine in newly diagnosed epilepsy

An international trial comparing remacemide hydrochloride with carbamazepine was undertaken in individuals with newly diagnosed epilepsy using a novel double-blind, parallel-group, double triangular sequential design. Patients with two or more partial or generalized tonic-clonic seizures in the previous year were randomized to remacemide or carbamazepine and titrated to a target dose of 600 mg/day. Subsequent dosage adjustments were allowed while maintaining the blind. Repeated assessments of neuropsychological function and mood were carried out using computerized and conventional measures. The trial was completed 20 months after initiation, following the second interim analysis. Efficacy as measured by seizure recurrence showed remacemide to be inferior to carbamazepine. Baseline cognitive and neuropsychological measures showed impairment across the whole patient population. Cognitive/neuropsychological performance at 8, 24, and 48 weeks was compared with that at baseline. Significant deterioration was seen on measures of information processing speed and attention after treatment with carbamazepine. The study data provide evidence for the utility and sensitivity of a number of cognitive assessments, which may be employed in future trials of antiepileptic drugs.

The effects of acute treatment with paroxetine, amitriptyline, and placebo on driving performance and cognitive function in healthy Japanese subjects: a double-blind crossover trial

OBJECTIVE

To assess the effects of antidepressants on driving performance from a different methodological viewpoint in light of the recent traffic accidents.

METHODS

In this double-blinded, 3-way crossover trial, 17 healthy males received acute doses of 10 mg paroxetine, 25 mg amitriptyline, and placebo. The subjects were administered three driving tasks--road tracking, car following, and harsh braking--performed using a driving simulator and three cognitive tasks--Wisconsin Card Sorting Test, Continuous Performance Test, and N-back test at baseline and at 1 h and 4 h post-dosing. The Stanford Sleepiness Scale scores were also assessed.

RESULTS

At 4 h post-dosing, amitriptyline significantly impaired road-tracking and car-following performance, reduced driver vigilance, and caused subjective somnolence. Paroxetine impaired neither driving performance nor cognitive function.

CONCLUSIONS

Acute doses of amitriptyline significantly impaired driving performance in the context of driving on crowded urban roads at relatively low speeds. This setting is important with respect to skills necessary for daily driving and may be difficult to measure in actual driving tests. This simulator-based study replicated the results of previous studies and could be considered complementary to them. This method may enable easy and safe screening of the driving hazard potential of drugs.

Effects of a sedative antihistamine, D-chlorpheniramine, on regional cerebral perfusion and performance during simulated car driving

OBJECTIVES

The sedative side effects of antihistamines have been recognized to be potentially dangerous in car driving, but the mechanism underlying these effects has not yet been elucidated to date. The aim of the present study is to examine regional cerebral blood flow (rCBF) responses during a simulated car-driving task following oral administration of D-chlorpheniramine using positron emission tomography (PET) and [15O]H2O, based on a single-blind cross-over study-design.

METHODS

Right-handed, healthy male volunteers (n = 14) drove a car in a simulated environment following oral administration of D-chlorpheniramine repetab 6 mg or placebo. Their rCBF was measured using PET with [15O]H2O in the following three conditions: (1) resting, (2) active driving, and (3) passive driving. All 'in-car' views during the simulated driving were videotaped and used for rating driving performance.

RESULTS

Performance evaluation revealed that the number of lane deviations significantly increased in the D-chlorpheniramine condition compared with the placebo condition (p < 0.01). Subjective sleepiness was not significantly different between the two drug conditions. The regions of diminished brain responses following D-chlorpheniramine treatment were detected in the parietal, temporal and visual cortices, and in the cerebellum. The regions of augmented rCBF responses were found in the orbitofrontal cortex and cerebellar vermis.

CONCLUSION

These results suggest that D-chlorpheniramine tends to suppress visuo-spatial cognition and visuo-motor coordinating functions rather than attention and motor functions during car driving.

Lack of effects between rupatadine 10 mg and placebo on actual driving performance of healthy volunteers

INTRODUCTION

Rupatadine fumarate is a potent, selective, histamine H(1)-receptor antagonist and PAF inhibitor with demonstrated efficacy for the relief of allergic rhinitis. Rupatadine does not easily cross the blood-brain barrier and is believed to be non-sedating at therapeutic doses. Consequently, rupatadine should show no impairment on car driving.

OBJECTIVE

This study compared the acute effects of rupatadine, relative to placebo and hydroxyzine (as an active control), on healthy subjects' driving performance.

METHODS

Twenty subjects received a single dose of rupatadine 10 mg, hydroxyzine 50 mg, or placebo in each period of this randomized, double-blind, three-way crossover study. Two hours postdosing, subjects operated a specially instrumented vehicle in tests designed to measure their driving ability. Before and after the driving tests ratings of sedation were recorded.

RESULTS

There was no significant difference between rupatadine and placebo in the primary outcome variable: standard deviation of lateral position (SDLP); however, hydroxyzine treatment significantly increased SDLP (p < 0.001 for both comparisons). Objective (Stanford sleepiness scale) and subjective sedation ratings (Visual Analogue Scales) showed similar results: subjects reported negative effects after hydroxyzine but not after rupatadine.

CONCLUSION

Rupatadine 10 mg is not sedating and does not impair driving performance.

Stimulant effects of 3,4-methylenedioxymethamphetamine (MDMA) 75 mg and methylphenidate 20 mg on actual driving during intoxication and withdrawal

BACKGROUND

3,4-methylenedioxymethamphetamine (MDMA) is currently one of the most popular drugs of abuse in Europe. Its increasing use over the last decade has led to concern regarding possible adverse effects on driving. The aims of the present study were to investigate the acute effects of MDMA on actual driving performance during the intoxication and withdrawal phase.

METHODS

Eighteen recreational MDMA-users (nine males, nine females) aged 21-39 years participated in a double-blind, placebo-controlled, three-way cross-over study. MDMA 75 mg, methylphenidate 20 mg and placebo were administered on day 1 of treatment (intoxication phase). Driving tests were conducted between 3 and 5 hours post-drug. Subjects returned the following day for a repetition of the driving tests between 27 and 29 hours post-drug (withdrawal phase). On-the-road driving tests consisted of a road-tracking test and a car-following test. Its main parameters were standard deviation of lateral position (SDLP), time to speed adaptation (TSA), brake reaction time (BRT) and gain.

FINDINGS

MDMA and methylphenidate significantly decreased SDLP in the road-tracking tests by about 2 cm relative to placebo on day 1 (intoxication phase). In addition, MDMA intoxication decreased performance in the car-following test as indicated by a significant rise in the 'overshoot' of the subjects' response to speed decelerations of the leading vehicle. Driving performance was not affected by treatments during withdrawal on day 2.

CONCLUSION

Collectively, these data indicate that MDMA is a stimulant drug that may improve certain aspects of the driving task, such as road-tracking performance, but may reduce performance in other aspects of the driving task, such as accuracy of speed adaptation during car-following performance.

Driving impairment in depressed patients receiving long-term antidepressant treatment

BACKGROUND

Depression is a common mental disorder with cognitive deficits, but little information is available on the effects of antidepressant treatment on driving performance in depressed patients.

AIMS

Assessing actual driving performance and cognition of depressed patients receiving long-term antidepressant treatment.

MATERIALS AND METHODS

Performance was assessed in depressed patients receiving selective serotonin reuptake inhibitor (SSRI) or serotonin and noradrenalin reuptake inhibitor (SNRI) treatment for 6-52 weeks and in matched healthy controls by means of two standardised on-the-road driving tests and laboratory tests of cognition.

RESULTS

Data showed poorer driving performance as indicated by a higher standard deviation of lateral position or 'weaving motion' in medicated patients relative to controls. Time to speed adaptation and critical flicker fusion threshold were also impaired in medicated patients. The Hamilton Depression Rating Scale scores in medicated patients were significantly higher as compared to that of controls. No other significant results between the two groups were demonstrated on the variables of the driving tests and laboratory tests of cognition.

CONCLUSIONS

The depressed patients receiving long-term treatment with SSRI- and SNRI-type antidepressants show impaired driving performance. This impairment in driving performance can probably be attributed to residual depressive symptoms instead of the antidepressant treatment.

Mortality among subjects previously apprehended for driving under the influence of traffic-hazardous medicinal drugs

BACKGROUND

Most studies in the field of impaired driving have focused on the hazards represented by impaired drivers to the rest of society; there has been little follow-up of the drivers themselves. The aim of this study was to establish mortality rates among subjects previously apprehended for driving under the influence of traffic-hazardous medicinal drugs, alone or in combination with alcohol.

METHODS

A prospective cohort study of all drivers aged 20-49 years, apprehended in Norway in 1992-1996 and testing positive for traffic-hazardous medicinal drugs in blood, outcome variable: death.

STUDY POPULATION

805 drivers (598 males, 207 females). Mean follow-up period: 6.8 years. Information on deaths was collected from Statistics Norway.

RESULTS

During the follow-up period, 139 of the previously apprehended drivers died (110 males, 29 females). The calculated standardised mortality ratio (SMR) was 15.8 (95% CI: 13.0-19.0) for male and 20.0 (95% CI: 13.4-28.7) for female drivers.

CONCLUSIONS

Apprehension on suspicion of driving under the influence of drugs, combined with detection of traffic-hazardous medicinal drugs in the blood, seems to indicate an elevated risk of premature death in the age group 20-49 years. Secondary prevention of continued drug use could save lives in this drug user group.

The effect of opioids on driving and psychomotor performance in patients with chronic pain

OBJECTIVES

This study compared the psychomotor performance and driving ability of patients with chronic pain managed with stable regimens of opioid analgesics with that of normal healthy volunteers. The hypothesis was that patients with chronic pain on stable opioid analgesic regimens operate their automobiles safely with proficiency equal to normal volunteer controls.

METHODS

Patients were evaluated for errors while driving their own automobile through a predetermined route in the community, including variable residential and highway conditions, and for speed and accuracy on repeated trials through a 5-station obstacle course that evaluated forward and reverse driving, turning, and parallel parking. Patients also completed the Test of Variables of Attention and the Digit Symbol Substitution Test.

RESULTS

No significant differences were observed among groups in driving performance in the community and on the obstacle course or on the Test of Variables of Attention. Results on dependent measures within the opioid group generally were not correlated with morphine equivalent daily opioid doses, which averaged 118 mg (median 40 mg).

CONCLUSIONS

Many patients with chronic pain, even if treated with potent analgesics such as morphine and hydromorphone, show comparable driving ability as normals.

A dose-ranging study of the effects of mequitazine on actual driving, memory and psychomotor performance as compared to dexchlorpheniramine, cetirizine and placebo

BACKGROUND

Mequitazine is a so-called 'non-sedative' second-generation antihistamine even though it has never been firmly established that this drug's sedative potential actually differs from that of the 'sedative' first-generation antihistamines.

OBJECTIVE

The present study compares the sedative effects of three doses of mequitazine on actual driving, psychomotor performance and memory with those of a first- and a second-generation antihistamine.

METHODS

Eighteen healthy volunteers received on separate days a single dose of 5, 10 and 15 mg mequitazine, 10 mg cetirizine, 6 mg dexchlorpheniramine and placebo. Drug effects were assessed using two actual driving tests (highway-driving test and car-following test), cognitive and psychometric tests (tracking, divided attention, memory, reasoning and critical flicker fusion), pupil size and questionnaires.

RESULTS

Highway-driving data revealed an overall effect of Treatment on the standard deviation of lateral position (SDLP). Dexchlorpheniramine impaired driving performance as indicated by a significant rise in SDLP. Mequitazine significantly increased SDLP in a dose-related manner, but the separate dose effects failed to reach statistical significance. Divided attention performance was also affected by Treatment. Reaction time (RT) during mequitazine treatments increased in a dose-related manner and significantly differed from placebo at the highest dose. Subjects reported to be less alert after treatment with dexchlorpheniramine. Cetirizine did not affect performance in any of the tasks.

CONCLUSION

It was concluded that mequitazine is mildly sedating. The effects of mequitazine are comparable to those of other second-generation antihistamines, in that it causes mild driving impairment, particularly at higher doses.