The hazards of sleep deprivation | Marta Ann Crispens, MD, MBA, FACOG
A recent study in the New England Journal of Medicine reported that within the constraints of an 80-hour work week, more flexible work hour restrictions for internal medicine residents that did not specify shift lengths or time off between shifts did not adversely affect 30-day mortality or other measures of patient safety.1 A randomized trial of surgical residents similarly found that less restrictive work hours was associated with non-inferior patient outcomes as compared to a more restrictive work hours policy.2 But what if this is the wrong question? Perhaps the question is not how to optimize the 80-hour week, but whether it is possible to reconcile the 80-hour week and 24-hour shifts with the realities of human physiology.
Sleep deficiency, defined as both inadequate and mistimed sleep, is an under-recognized health risk.3 Studies performed in rats and dogs demonstrate that the result of prolonged sleep deprivation is death.4,5 More recent studies in rats have shown that repeated exposure to severely limited sleep results in persistent physiological imbalances.6 In humans, sleep deprivation is associated with major health risks, including cardiovascular disease, obesity, type 2 diabetes, and cancer.3 Sleep deprivation results in impairment of cognitive and motor performance comparable to being drunk.7 The optimal sleep time for an adult is 7 to 8 hours per night.3
Software developers were long known for eschewing sleep and working long hours to complete projects. That is, until it was recognized that long hours led to decreasing creativity and productivity and increasing rates of programming errors. Agile is a set of values and principles for software development.8 The eighth agile principle is sustainable pace, that is a work pace that the team would be able to sustain indefinitely.9 This idea derives from the observation, often attributed to Henry Ford, that productivity declines after 40 hours per week of work – and perhaps 35 hours for knowledge workers.10, 11
More recent academic analyses have confirmed that longer work hours result in employee fatigue and stress that reduces productivity and increases the probability of errors, accidents, and illness.12 There is an irony in the observation that the information technology sector has recognized and acted upon the realities of human physiology before doctors.
We face a number of challenges in medicine including burnout, suicide, and medical errors. Although there are many contributors, sleep deprivation is an important factor. The United States has adopted work hour restrictions for physicians in training that are less restrictive than those imposed for airline pilots or truck drivers.13, 14 There are no work hour restrictions for physicians in practice. There are two main challenges to decreasing resident work hours, the need for more providers to supply patient care and a decrease in educational opportunities for residents. Several countries in northern Europe have successfully achieved reductions in resident duty hours to 48 hours or less with continued provision of safe patient care and satisfactory training.15
There will always be the challenge that patients require care 24/7/365. However, the goals of maximizing patient safety and achieving a healthy work-life balance and better overall health for all providers during and after training require that we rethink the organization of healthcare systems and training to find our sustainable pace.
Marta Ann Crispens, MD, MBA, FACOG, is a Professor and Director, Division of Gynecologic Oncology, in the Department of Ob/Gyn and Chair of the Vanderbilt-Ingram Cancer Center Scientific Review Committee at Vanderbilt University Medical Center in Nashville, TN.
- Silber JH, Bellini LM, Shea JA, et al. Patient safety outcomes under flexible and standard resident duty-hour rules. N Engl J Med 2019;380:905-914.
- Bilimoria KY, Chung JW, Hedges LV, et al. National cluster-randomized trial of duty hour flexibility in surgical training. N Engl J Med 2016;374:713-27.
- Luyster FS, Strollo PJ Jr, Zee PC, et al. Sleep: A health imperative. Sleep 2012;35:727-34.
- Rechtschaffen A, Bergmann BM. Sleep deprivation in the rat: An update of the 1989 paper. Sleep 2002;25:18-24.
- Bentivoglio M, Grassi-Zucconi G. The pioneering experimental studies on sleep deprivation. Sleep 1997;20:570-6.
- Everson CA, Szabo A. Repeated exposure to severely limited sleep results in distinctive and persistent physiological imbalances in rats. PLoS One 2011;6:e22987.
- Williamson AM, Feyer AM. Moderate sleep deprivation produces impairments in cognitive and motor performance equivalent to legally prescribed levels of alcohol intoxication. Occup Environ Med 2000;57:649-55.
- Agile Alliance. Agile 101.
- Agile Alliance. Sustainable Pace.
- International Game Developers Association (igda). Why crunch modes don’t work: Six lessons.
- Cook D. Lost Garden. Laws of productivity. September 28, 2008.
- Pencavel J. The productivity of working hours. The Economic J 2015;589:2052-76.
- Federal Aviation Administration. Fact sheet-Pilot fatigue rule comparison. December 11, 2011.
- Federal Motor Carrier Safety Administration. Summary of hours of service regulations. March 9, 2017.
- Temple, J. Resident duty hours around the globe: Where are we now? BMC Med Ed 2014;14:58-62.