Highway driving safety the day after using sleep medication: the direction of lapses and excursions out-of-lane in drowsy drivers.

The primary outcome measure of the on-road driving test is the Standard Deviation of Lateral Position. However, other outcome measures, such as lapses and excursions out-of-lane, also need to be considered as they may be related to crash risk. The aim of this study was to determine the direction of lapses and excursions out-of-lane (i.e. towards/into the adjacent traffic lane or towards/into the road shoulder). In total, data from 240 driving tests were re-analysed, and 628 lapses and 401 excursions out-of-lane were identified. The analyses revealed that lapses were made equally frequently over left (49.4%) and over right (43.3%). In contrast, excursions out-of-lane were almost exclusively directed over right into the (safer) road shoulder (97.3%). These findings suggest that drivers are unaware of having lapses, whereas excursions out-of-lane are events where the driver is aware of loss of vehicle control.

The effects of intranasal esketamine (84 mg) and oral mirtazapine (30 mg) on on-road driving performance: a double-blind, placebo-controlled study.

RATIONALE: The purpose of this study is to evaluate the single dose effect of intranasal esketamine (84 mg) compared to placebo on on-road driving performance. Mirtazapine (oral, 30 mg) was used as a positive control, as this antidepressant drug is known to negatively affect driving performance. METHODS: Twenty-six healthy volunteers aged 21 to 60 years were enrolled in this study. In the evening, 8 h after treatment administration, participants conducted the standardized 100-km on-road driving test. Primary outcome measure was the standard deviation of lateral position (SDLP), i.e., the weaving of the car. Mean lateral position, mean speed, and standard deviation of speed were secondary outcome measures. For SDLP, non-inferiority analyses were conducted, using +2.4 cm (relative to placebo) as a predefined non-inferiority margin for clinical relevant impairment. RESULTS: Twenty-four participants completed the study. No significant SDLP difference was found between esketamine and placebo (p = 0.7638), whereas the SDLP after mirtazapine was significantly higher when compared to placebo (p = 0.0001). The upper limit of the two-sided 95% confidence interval (CI) of the mean difference between esketamine and placebo was +0.86 cm, i.e., <+2.4 cm, thus demonstrating that esketamine was non-inferior to placebo. Non-inferiority could not be concluded for mirtazapine (+3.15 cm SDLP relative to placebo). No significant differences in mean speed, standard deviation of speed, and mean lateral position were observed between the active treatments and placebo. CONCLUSIONS: No significant difference in driving performance was observed 8 h after administering intranasal esketamine (84 mg) or placebo. In contrast, oral mirtazapine (30 mg) significantly impaired on road driving performance.

Hangover resistance in a Canadian University student population.

BACKGROUND: Resistance to alcohol hangover may be a risk factor for alcohol use disorder. Previous research to establish the prevalence of hangover resistance in a drinking population has either not used comparable intoxication levels or has considered hangover resistance over a limited time frame. The purpose of this study was to examine the prevalence of lifetime hangover negative (LHN) drinkers across comparable eBAC values ranging from 0 to 500 mg/dl. METHODS: Students at an eastern Canadian university were surveyed about their heaviest drinking episode in the past month and indicated whether they had ever experienced a hangover in their lifetime (LHN) and, if they had, the hangover severity they experienced the next day. eBACs were calculated and the percentage of LHN drinkers was computed at each 10 mg/dl eBAC increment from 0 to 500 mg/dl. RESULTS: Most LHN drinkers (58% female, 71% male) had an eBAC on their heaviest drinking occasion below 80 mg/dl. Above eBACs of 80 mg/dl, 5.8% of female and 5.1% of male drinkers were lifetime hangover negative. CONCLUSIONS: The results suggest that only a small percentage of heavy drinkers lay claim to being lifetime hangover negative.

Effects of alcohol hangover on simulated highway driving performance.

BACKGROUND: The purpose of this study was to examine the effects of alcohol hangover on simulated highway driving performance. METHODS: Driving performance of forty-two social drinkers was tested the morning following an evening of consuming on average 10.2 (SD = 4.2) alcoholic drinks (alcohol hangover) and on a control day (no alcohol consumed). Subjects performed a standardized 100-km highway driving test in the STISIM driving simulator. In addition to the standard deviation of lateral position (SDLP; i.e., the weaving of the car), lapses of attention were examined. Self-reported driving quality and driving style were scored, as well as mental effort to perform the test, sleepiness before and after driving, and hangover severity. RESULTS: Driving performance was significantly impaired during alcohol hangover as expressed by an SDLP increase of +1.9 cm (t (1,41) = 2.851, p = 0.007), increased number of lapses relative to the control day (7.7 versus 5.3 lapses, t (1,41) = 2.125, p = 0.019), and an increased total lapse time (182.7 versus 127.3 s, p = 0.040). During alcohol hangover, subjects reported their driving quality to be significantly poorer (t (1,41) = 4.840, p = 0.001) and less safe (t (1,41) = 5.078, p = 0.001), wise (t (1,41) = 4.061, p = 0.001), predictable (t (1,41) = 3.475, p = 0.001), and responsible (t (1,41) = 4.122, p = 0.001). Subjects further reported being significantly more tense while driving (t (1,41) = 3.280, p = 0.002), and more effort was needed to perform the driving test (t (1,41) = 2.941, p = 0.001). There was a significant interaction with total sleep time and hangover effects on SDLP and the number of lapses. CONCLUSIONS: In conclusion, driving is significantly impaired during alcohol hangover, as expressed in an elevated SDLP and increased number of lapses. Total sleep time has a significant impact on the magnitude of driving impairment.

Lapses of attention as outcome measure of the on-the-road driving test.

BACKGROUND: Lapses are brief periods of inattention and reduced alertness which may be a risk factor for car crashes. The Dutch on-the-road driving test is applied to examine effects of CNS drugs on driving, using the standard deviation of lateral position (SDLP) as primary outcome measure. This paper examines the utility of an alternative outcome measure, lapses, to determine the degree to which CNS drugs impair driving. METHODS: Data from two double-blind, placebo-controlled on-the-road driving studies that examined the residual effects of hypnotic drugs were reanalyzed. The treatments were zaleplon and zolpidem tested 4 h after middle-of-the-night administration, and ramelteon and zopiclone tested 8.5 h after bedtime administration. In addition to SDLP, outcome measures related to lapses (number, total duration, and maximum deviation) were computed. A lapse was defined as a continuous change in lateral position of greater than 100 cm, lasting for at least 4 s. RESULTS: Both SDLP and lapses were able to detect significant driving impairment after middle-of-the-night administration of zolpidem (10 and 20 mg) and bedtime administration of ramelteon (8 mg) and zopiclone (7.5 mg) relative to placebo. Both measures found no differences from placebo after middle-of-the-night administration of zaleplon (10 and 20 mg). The number of lapses was more sensitive in differentiating treatment from placebo than the maximum deviation of a lapse or their duration. After considering different lapse duration criteria, a lapse was redefined as a continuous change in lateral position of greater than 100 cm, lasting for at least 8 s. This change in definition did not significantly alter the outcome of the statistical analyses. CONCLUSIONS: In addition to SDLP, the number of lapses is a useful outcome measure to identify treatments that impair driving. Future research should determine the unique contributions of SDLP and lapses in defining the potential risk of CNS drugs on driving.