Fatigue has been linked to a range of undesirable outcomes. These include lapses of attention and microsleeps, reduced reaction time, and impaired risk awareness and decision making (1); large-scale industrial disasters, including nuclear power plant meltdowns (2); increased workplace fatalities and injuries (3,4); and impaired health. Sleep loss is often a key contributor for fatigue, and indeed, ongoing sleep loss has been linked to increased rates of hypertension, cardiovascular disease, diabetes, and also all-cause mortality (5).
However, fatigue may also result in other negative outcomes that are relevant to consider. For instance, fatigue results in significant costs to the community, which have been estimated to be around $80 billion annually (6). In Australia, this figure may be at least $3 billion (7). A reason for this cost may relate to direct costs to employers and the community due to workplace injuries and incidents, and also due to losses in productivity (including covering for lost workers).
One study which looked at the impact of sleeping disorders (e.g. insomnia) on workplace productivity found that those with insomnia (compared to people without insomnia) had a reduced performance output of 4% (9) across the US, this resulted in increased annual costs of $41.1 billion US dollars. Longer working hours, which may be reflective of fatigue and/or reduced sleep, have also shown to reduce productivity. For instance, it has been stated that “employee productivity per hour for 10- to 12-hour shifts is significantly lower than for an 8-hour shift” (8, pg. 16). Figure 1 highlights how productivity decreases with increasing sleep disturbance.
Figure 1. Increase in productivity loss (as a percentage) as a function of sleep disruption. Note that as sleep disruption increases—thereby acting as a surrogate of fatigue—productivity losses increase. Retrieved from (9).
Other significant sources of added costs and reduced productivity to employers is because of fatigue-related lost productive time (LPT). LPT includes both time away from work (absenteeism), and time at work but not performing at full capacity due to fatigue (presenteeism). Again in the US, the prevalence of fatigue across a national cross-section of workers found that fatigue was extremely prevalent, at 37.9% of the tested population (10). Of those reporting fatigue, nearly 66% reported health-related lost productive time, compared to 26.4% of those not reporting fatigue. When fatigue co-occurred with other conditions (e.g. pain, digestive problems, cold/flu, diabetes), there was an average of a threefold increase in the number of workers reporting significant LPT. In this study, fatigued workers were estimated to cost employers $136.4 billion annually in health-related LPT; greater than other estimates (10).
Employee sickness absence from work can no doubt be a considerable expense to employers. A recent study from Sweden studied the links between sickness absence and sleeping disturbances and fatigue (11). This was deemed important given that the rate of long-term sickness absence exceeding 90 days has doubled between 1993 to 2001 (11). Of a national sample of 8300 individuals over a two year period, it was found that those whom reported sleeping disturbances or fatigue at the start of the two year collection period were 1.24 and 1.35 times higher (respectively) of entering long-term sickness absence (exceeding 90 days) over the period. Similar results were found even after adjusting for a range of confounding factors.
Taken together, the studies cited in this article suggest that besides meeting legal work health and safety duties, of which breaches can result in severe financial penalties, managing occupational fatigue and sleeping disturbances make good business sense with respect to bottom-line productivity and operating costs.
- SafetyNet. (2009). Fatigue. Retrieved September 25, 2013.
- Dinges, D.F. (1995). An overview of sleepiness and accidents. J Sleep Res., 4(S2), 4-14.
- Akerstedt, T., Fredlund, P., Gillberg, M., & Jansson, B. (2002). A prospective study of fatal occupational accidents—Relationship to sleeping difficulties and occupational factors. Journal of Sleep Research, 11, 69–71.
- Uehli, K., Mehta, A.J., Miedinger, D., Hug, K., Schindler, C., Holsboer-Trachsler, E., Leuppi, J.D., & Künzli, N. (2013). Sleep problems and work injuries: A systematic review and meta-analysis. Sleep Med Rev., pii: S1087-0792(13)00008-7. doi: 10.1016/j.smrv.2013.01.004.
- Alvarez, G.G., & Ayas, N.T. (2004). The impact of daily sleep duration on health: a review of the literature. Prog Cardiovasc Nurs., 19(2), 56-9.
- Moore-Ede M. (1993) The twenty-four hour society: understanding human limits in a world that never stops. Reading, MA: Addison-Welsely Publishing.
- House of Representatives Standing Committee on Communications, Transport and the Arts. (2000). Beyond the Midnight Oil: Managing Fatigue in Transport. Parliament of Australia, Canberra.
- Dawson, D., McCulloch, K., & Baker, A. (2001). Extended working hours in Australia: counting the costs, commissioned by the Queensland Department of Industrial Relations, Adelaide, Centre for Sleep Research.
- Zammit et al. (2010). Impact of nighttime awakenings on worker productivity and performance. J Occup Environ Med., 52(5), 513-8.
- Ricci, J.A., Chee, E., Lorandeau, A.L., & Berger, J. (2007). Fatigue in the U.S. workforce: prevalence and implications for lost productive work time. J Occup Environ Med., 49(1), 1-10.
- Akerstedt, T., Kecklund, G., Alfredsson, L., & Selen, J. (2007). Predicting long-term sickness absence from sleep and fatigue. J Sleep Res., 16(4), 341-5.