Healthcare professionals, pilots, truck drivers and shift workers have likely all experienced sleep deprivation, which negatively affects performance, safety, and quality of life. Researchers have developed a blood test that can accurately detect whether someone has been awake for 24 hours or more.
Sleep deprivation can increase the risk of road and workplace accidents occurring, which also increases the likelihood of serious injury or fatality to self and others. It's also been linked to disease. Lack of sleep is common in our modern society, the result of competing demands for work, study, and family responsibilities and recreational activities.
While tools that measure pupillary response, slow eye closures, and microsleep have been developed to gauge sleep deprivation, their results can be confounded by other factors associated with accidents, such as light and epinephrine (or adrenaline) levels. Now, researchers from Monash University led a study to develop a blood test that accurately detects when someone hasn’t slept for 24 hours.
“This is a really exciting discovery for sleep scientists, and could be transformative to the future management of health and safety relating to insufficient sleep,” said Clare Anderson, the study’s corresponding author. “While more work is required, this is promising first step.”
Using a machine learning algorithm, the researcher identified a suite of metabolites – a substance created when the body breaks down food, drugs, chemicals or its own tissues – that predicted sleep deprivation across 40 hours of wakefulness. When they tested the biomarker, they found that it detected people who’d been awake for 24 hours with a 99.2% probability of being correct when compared to their own well-rested sample. When the well-rested sample wasn’t used for comparison, the test’s probability fell to 89.1%, which is still high.
The researchers hope that their test will inform future tests that can identify sleep-deprived drivers simply, quickly, and accurately or be used in safety-critical workplaces.
“There is strong evidence that less than five hours’ sleep is associated with unsafe driving, but driving after 24 hours awake, which is what we detected here, would be at least comparable to more than double the Australian legal limit of alcohol performance-wise,” Anderson said.
They foresee their test being used similarly to a test for alcohol concentration or the presence of drugs in drivers.
“Next steps would be to test it in a less controlled environment and maybe under forensic conditions, particularly if it was to be used as evidence for crashes involving drivers falling asleep,” said Katy Jeppe, lead author of the study. “Given it’s blood, the test is more limited in a roadside context, but future work could examine whether our metabolites, and therefore the biomarker, are evident in saliva or breath.”
But this will require further research and testing.
“Much further work would be needed if laws were to change and a sleep deprivation test introduced on the road or in workplaces,” Jeppe said. “This would include further validation of biomarkers, as well as establishing safe levels of sleep to prevent and recover from impairment, not to mention the extensive legal process.”
Currently, the test detects if someone has been awake for 24 hours or more, but the researchers say it can detect wakefulness down to 18 hours.
“A biomarker for limited sleep over the previous night could be developed, and others have made progress in this respect,” said Jeppe.
Ultimately, the researchers see their novel test as potentially game-changing.
“Objective tests that identify individuals who present as a risk to themselves or others are urgently needed in situations where the cost of a mistake is fatal,” said Anderson. “Alcohol testing was a game-changer for reducing road crashes and associated serious injuries and fatalities, and it is possible that we can achieve the same with fatigue. But much work is still required to meet this goal.”
The study was published in the journal Science Advances.
Source: Monash University
