Lapses of attention during driving in the alcohol hangover state

Background. The morning after a drinking session, i.e. during the alcohol hangover state, people commonly report reduced alertness and ability to concentrate. Thus, it is likely that lapses of attention may occur. These lapses may compromise safety in potentially dangerous activities such as driving a car. The purpose of this study was to examine the presence of lapses of attention during driving in the hangover state. Methods. In N = 47 healthy volunteers, driving performance was tested the morning following an evening of consuming on average 10.2 (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 when BAC was zero. Lapses of attention were examined, defined as a continuous change of lateral position >100 cm for at least 8 seconds. The number of lapses, maximum lateral deviation, and total time of lapses were computed. Results were compared with subjective assessments of driving quality and driving style. Hangover severity was scored with a visual analog scale ranging from 0 (absent) to 10 (extreme). Δlapses (hangover - control) was related to subjective outcome measures. Results. Data from 4 subjects were excluded as they reported that they had no hangover. Another subject was excluded because he scored positively (6out of 10) on the hangover scale on the control day. Data from N = 42 subjects are presented.During hangover, a significantly increased number of lapses relative to the control day (7.7 versus 5.3 lapses, p = 0.019), and an increased total lapse time (182.7 versus 127.3 seconds, p = 0.040) were observed. The maximum lapse deviation did not differ between hangover and control sessions (p = 0.130). Δlapses was significantly correlated to difference scores on subjective driving quality (p = 0.025) and mental effort to perform the test (p = 0.042). Δlapses was not significantly related to subjective assessments of driving style, sleep quality, or sleepiness scores obtained before or after driving. Driving impairment was significantly related to hangover severity scores. A significant positive relationship was found between difference scores on hangover severity and number of lapses (r = 0.373, p = 0.015) and total lapse time (r = 0.380, p = 0.013). There was no relationship with the number of consumed alcoholic drinks the night before. Conclusions. Driving is significantly impaired during alcohol hangover. Funding: This study was funded by Utrecht University.