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High Drowsy Driving Crash Risk on Daytime Commute after Night Work

December 21, 2015




New research from Brigham and Women’s Hospital (BWH) and the Liberty
Mutual Research Institute for Safety published by Proceedings of the National
Academy of Sciences
evaluated the daytime driving performance of night shift
workers after a night of shift work compared to driving after a night of sleep, and
found that 37.5 percent of drivers participating in a test drive after working the night
shift were involved in a near-crash event. The same drivers, with normal sleep the night before the test, had zero near-crashes. These results demonstrate, for the first time, an increased risk of drowsy driving related motor vehicle crashes, as well as an increase in self-reported and biological measures of drowsiness when operating a real motor vehicle during the daytime following night shift work.

“Drowsy driving is a major–and preventable–public health hazard,” said Charles A. Czeisler,
PhD, MD, FRCP, chief of the Division of Sleep and Circadian Disorders at BWH, and
corresponding author of the study. “These findings help to explain why night shift workers have so many more motor vehicle crashes than day workers, particularly during the commute home.Night shift workers should be advised of the hazards of drowsy driving and seek alternate forms of transportation after night shift work.”

“Even veteran night shift workers were vulnerable to the risks associated with drowsy driving, and exhibited reactions similar to behaviors observed in drivers with elevated blood
alcohol concentrations,” said Michael L. Lee, PhD, lead author, and research fellow in the Division of Sleep and Circadian Disorders at BWH. “A short commute for these drivers is shown to be potentially dangerous and the longer the drive, the greater the risk. Education about drowsy driving and its potential hazards could minimize this risk by prompting shift workers to eliminate or reduce the need to drive after night shift work, and to stop driving when their performance is impaired by drowsiness.”

Access the full article here.

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This study was supported by a grant from the Institute of Breathing and Sleep Research,
Heidelberg, Victoria, Australia; Liberty Mutual Insurance; the National Institutes of Health
award 5T32HL7901-14; the National Space Biomedical Research Institute award PF03002; the Department of Homeland Security Federal Emergency Management Agency Assistance to
Firefighter Grant EMW-2010-FP-00521; National Heart, Lung and Blood Institute Cooperative
Agreement U01-HL111478; National Institute of Occupational Safety and Health grant R01-
OH0103001; National Institute on Aging Grant R01-AG044416.

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