Research by AAA found that drowsy drivers pose more danger on the road than previously thought.

Its Foundation for Traffic Safety study showed that an estimated 6,725 were killed in accidents caused by sleepy drivers in 2021 and that 18% of all traffic deaths from 2017 to 2021 involved drivers compromised by inadequate rest, leading to almost 30,000 fatalities.

AAA pointed out that the numbers, which are based on crash investigations and national fatal-accident data, exceed government estimates of the toll of drowsy driving by about 10-fold.

In fact, the federal government’s own National Highway Traffic Safety Administration says its peer organizations, sleep scientists and public health agencies agree that sleep deprivation’s impact on driving is underestimated. For instance, the NHTSA’s own report estimates that 2021 traffic deaths related to drowsy driving totaled 684, compared to the new AAA figure of 6,725.

One of the dangers of sleepy drivers is their lack of awareness of how tired they are, AAA said, citing its own previous research.

It said it supports development of vehicle technology to detect drowsy driving and prevent people from driving while impaired by lack of adequate rest.

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