Moderate sleep deprivation produces impairments in cognitive and motor performance equivalent to legally prescribed levels of alcohol intoxication

Abstract

Objectives-To compare the relative effects on performance of sleep deprivation and alcohol. Methods-Performance eVects were studied in the same subjects over a period of 28 hours of sleep deprivation and after measured doses of alcohol up to about 0.1% blood alcohol concentration (BAC). There were 39 subjects, 30 employees from the transport industry and nine from the army. Results-After 17-19 hours without sleep, corresponding to 2230 and 0100, performance on some tests was equivalent or worse than that at a BAC of 0.05%. Response speeds were up to 50% slower for some tests and accuracy measures were significantly poorer than at this level of alcohol. After longer periods without sleep, performance reached levels equivalent to the maximum alcohol dose given to subjects (BAC of 0.1%). Conclusions-These findings reinforce the evidence that the fatigue of sleep deprivation is an important factor likely to compromise performance of speed and accuracy of the kind needed for safety on the road and in other industrial settings. (Occup Environ Med 2000;57:649-655) Keywords: sleep deprivation; performance; alcohol The implications of fatigue for safe performance are well recognised particularly in road safety, but in other settings as well. Fatigue is most likely to occur when rest is reduced such as when working long or irregular hours, doing shift and night work, or due to family responsibilities or lifestyle choices. EVects of fatigue are thought to play a part in between 16% and 60% of road accidents 1 2 and in the United States were estimated to cost in the vicinity of $50 billion. Recently authors have argued that until now society has simply accepted the hazards of fatigue despite evidence of increased risk to health and safety.4 5 This has led to calls for better information on the extent and consequences of the eVects of fatigue on performance.6 The problem, in practice, is at what level of fatigue does performance become a problem? In setting any safety standard for the fatigue caused by sleep deprivation, the sort of information needed is a comparison of performance after a known number of hours spent awake with that caused by some other agent that decreases performance.Alcohol eVects serve as a good model for an acceptable standard for safe performance. Alcohol eVects have been measured and standardised by setting limits on alcohol consumption based on their predicted eVects on driving performance.7 Many countries have set limits for alcohol levels while driving which are based on laboratory, simulator, and on road measures of speed and accuracy of performance.8 These standards provide a benchmark for performance deficits caused by injury, illness, or in this case, the fatigue of sleep deprivation. By comparing the change in performance due to alcohol consumption at concentrations widely agreed to be hazardous (0.05% blood alcohol concentration (BAC)) 8 with the same behaviour after sleep deprivation, it should be possible to assess the amount of sleep deprivation at which equivalent deficits occu...

Consequences of sleep deprivation

“…Prolonged microepisodes of sleep during driving considerably reduce the driving safety [59]. With regard to such parameters as the concentration of attention, reflexes, perceptiveness and accuracy of task performance, the effects of a 24-hour sleep deprivation, or of a 4-5-hour night sleep repeated over a period of one week, are similar to those induced by the 0.5-1‰ level of blood alcohol concentration [153][154][155][156][157]. In most of the European countries, the highest permissible blood level of alcohol in car drivers is 0.5‰, and the Polish law permits only the values below 0.2‰.…”

The Impact of Moderate Sleep Loss on Neurophysiologic Signals during Working-Memory Task Performance

“…33,35 This observation is consistent with other reports that have compared the effects of sleep deprivation and alcohol on performance. 66,78,79 In contrast, the magnitude of the behavior impairment associated with moderate sleep loss was not as great as that observed following a single standard 50-milligram dose of the over-the-counter antihistamine diphenhydramine in the same subjects. 34…”

An evaluation of senior house officer training in oral and maxillofacial surgery

“…1-3 These changes were made in an attempt to improve junior doctors' working lives and decrease the potential for errors due to lack of rest. [4][5][6][7][8][9][10] The 'New Deal' 1 and more recently the European Working Time Directive (EWTD) 2,3 both placed restrictions on the number of hours an individual can work and imposed minimum rest requirements. An individual can choose to opt out of the EWTD, but the rest break requirements are not negotiable.…”