Sleep Disorders & Road Safety

Are fatigue and sleepiness, the main symptoms of sleep apnea, major risk factors for road accidents? VitalAire Portugal has teamed up with the Portuguese Road Safety organization (PRP) to measure the impact of sleep disorders on driving. Is it comparable to the risks associated with driving under the influence of alcohol, speeding or distraction? Why are warning signs such as repeated yawning or difficulty keeping the eyes open not taken seriously by drivers? 

Fatigue and sleepiness at the wheel are often underestimated risk factors, yet they play a major role in road accidents. According to the study "Fatigue, Sleepiness and Sleep Disorders - Impact on Road Safety", carried out among 1,002 Portuguese drivers, fatigue accounts for 30% of road accidents.

Alarming data on fatigue and falling asleep at the wheel

The study carried out by Portuguese Road Safety (PRP) in partnership with VitalAire revealed a worrying reality.

What causes us to fall asleep at the wheel?

People with sleep apnea experience a fragmentation of their nocturnal rest. Their repeated micro-awakenings prevent efficient recovery, resulting in a chronic sleep debt that weakens their physical and mental capacities. In the sample, professional drivers, shift workers and young people are particularly vulnerable to fatigue due to irregular schedules and lifestyles that increase the risk of sleepiness at the wheel. Prolonged static position behind the wheel also favors the onset of sleepiness, particularly on long, monotonous journeys.

Risk perception and behavior

Although 86.9% of drivers agree that they should not drive while sleepy, and 91.4% admit that this condition increases the risk of an accident, a worrying number downplay the danger.

• 9.6% of those questioned said they would continue to drive even when tired;
• 18.4% think they can drive safely even when tired;
• 5.2% consider it acceptable to drive with difficulty keeping their eyes open.

Fatigue at the wheel: a neglected risk factor

Fatigue has a similar impact to driving under the influence of alcohol, excessive speed or distraction. The study reveals that 29.7% of drivers involved in an accident in the past year cite fatigue or sleepiness as the main cause. In addition, 44.9% said they had had a near-miss accident, 20.9% of which were related to fatigue or sleepiness.

What should you do if you're falling asleep at the wheel?

The most effective measures remain the least adopted:

• Stopping for a nap (11.2%), considered effective by 82.5% of drivers;
• Asking a passenger to take the wheel (13.0%), considered effective by 86.5%.

The impact of sleep disorders on driving

The study also revealed that one in five drivers is at high risk of suffering from obstructive sleep apnea, a condition that compromises rest quality and increases daytime sleepiness. In addition, 10.7% of drivers reported having a diagnosed sleep disorder, the most common being insomnia (53%) and sleep apnea (41%). Sleep debt significantly impairs reflexes. A night of disturbed sleep slows reaction time and reduces peripheral vision. As a result, anticipation skills are greatly diminished.

Awareness-raising and prevention

Many drivers underestimate the risks and overestimate their ability to cope with fatigue, using ineffective strategies that increase the risk of accidents

Alain Areal, President of Portuguese Road Prevention.

Reducing the number of accidents will require a 360° approach, combining information campaigns on the dangers of fatigue at the wheel; safer road infrastructures (such as rest areas and rumble strips); fatigue-detecting safety technologies; driver training and greater corporate involvement in the fight against fatigue at work.

In partnership with the road safety agency (Prevenção Rodoviária Portuguesa, PRP), Air Liquide Healthcare's home healthcare subsidiary in Portugal, VitalAire, consulted over 1,000 drivers. Online questionnaires were used to assess both their sleepiness and their risk of sleep apnea.