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