Sleep deprived people more likely to have car crashes

September 18, 2018

Science Daily/Oxford University Press USA

A new study indicates that people who have slept for fewer than seven of the past 24 hours have higher odds of being involved in and responsible for car crashes. The risk is greatest for drivers who have slept fewer than four hours.

Experts recommend that adults should sleep for seven to nine hours a night, yet government surveys indicate that one in five U.S. adults sleeps for fewer than seven hours on any given night, and one in three report usually sleeping for fewer than seven hours. An estimated seven percent of all motor vehicle crashes in the U.S. and 16 percent of fatal crashes involve driver drowsiness.

While the dangers of driving drowsy were already well known, this is the first peer-reviewed study to quantify the relationship between how much a driver has slept and his or her risk of being responsible for a crash. For this new study, researchers analyzed data from a previous study by the U.S. Department of Transportation, which involved in-depth investigations of a sample of 5,470 crashes, including interviews with the drivers involved.

The researchers here found that drivers who reported fewer than four hours of sleep had 15.1 times the odds of responsibility for car crashes, compared with drivers who slept for the recommended seven to nine hours in the preceding 24-hour period, comparable to U.S. Department of Transportation estimates of the crash risk of a driver with a blood alcohol concentration roughly 1.5 times the legal limit.

Researchers involved in the study also discovered that drivers who reported six, five, and four hours of sleep in the past 24 hours had 1.3, 1.9 and 2.9 times the odds of responsibility for a crash, respectively, compared with a driver who slept for seven to nine hours. Drivers who reported less than four hours of sleep had particularly elevated risk of single-vehicle crashes, which are more likely to result in injury or death. Drivers who had changed their sleep or work schedule in the past week and drivers who had been driving for 3 hours or longer without a break were also found to be at increased risk.

"Being awake isn't the same as being alert. Falling asleep isn't the only risk," said study author Brian Tefft. "Even if they manage to stay awake, sleep-deprived drivers are still at increased risk of making mistakes -- like failing to notice something important, or misjudging a gap in traffic -- which can have tragic consequences," he added.

https://www.sciencedaily.com/releases/2018/09/180918082041.htm

Zinc supplementation shows promise in reducing cell stress after blasts

- April 27, 2014

Science Daily/Federation of American Societies for Experimental Biology (FASEB)

Supplementation with zinc might reduce cell stress after the type of blast injury soldiers experience from IEDs, researchers say. Each year, approximately 2 million traumatic brain injuries (TBIs) occur in the USA, including with soldiers.

"We have nothing beyond ibuprofen for most TBIs," said Dr. Angus Scrimgeour, who has been investigating the effects of low zinc diets on cell stress following a blast injury. "The adult brain does not self-repair from this kind of trauma." Results of a new study suggest that zinc supplementation reduces blast-induced cell stress.

Scrimgeour works for the US Army Research Institute of Environmental Medicine and recently looked at the effects of 5-weeks of low and adequate zinc diets on a specific protein in muscle cells called MMP. The study recreated blast injuries in 32 rats similar to what soldiers experience from IEDs, including loss of consciousness. An equal number of rats served as a control group. Results suggest that zinc supplementation reduces blast-induced cell stress. He presented the results of his research at the American Society for Nutrition's Scientific Sessions & Annual Meeting at EB on Sunday, April 27.

"We know that soldiers' brain tissue cannot repair on low zinc diets," said Scrimgeour. "And they are losing zinc through diarrhea and sweating." The question moving forward is whether prevention through diet supplementation or post-blast treatment works best to repair behavioral deficits associated with mild TBI.

Scrimgeour added that further research is planned to investigate nutrient combinations for treating mild TBI, including omega-3, vitamin D, glutamine and/or zinc. Although the Army is conducting this research, the results can be applied outside of the military, according to Scrimgeour. "As the blast impact experienced by Soldiers are similar to those experienced during head injuries received in a car accident or during an NFL concussion, these findings could translate from the Soldier to the civilian population." Scrimgeour cautioned, however, that what works in animals doesn't always work in soldiers, which is why more research is needed.

http://www.sciencedaily.com/releases/2014/04/140427185159.htm