Untreated Sleep Apnea: The Quiet Danger on the Road

By Dr. David O. Volpi

It is common knowledge that untreated sleep apnea can have dire health effects, but researchers in England found out that loss of sleep also increases a person’s risk of nodding asleep at the wheel, and getting in a car accident. That endangers not only the person suffering from the sleep disorder, but any person driving around them at any given time.

The study, which was organized by the European Respiratory Society and the European Sleep Research Society, and presented April 12, 2013 at the Sleep and Breathing Conference in Berlin, determined that people with untreated sleep apnea are more likely to fail a driving simulator test, and report nodding asleep while driving.

Let’s review: What is sleep apnea?

Sleep apnea is a breathing disorder that causes a person’s breathing during sleep to be paused and/or shallow. The pauses generally last 10 to 20 seconds, and in severe cases, can occur hundreds of times a night. With obstructive sleep apnea (OSA), the airway is blocked and/or collapses while sleeping. Air squeezing by the blockage can cause loud snoring and interrupted sleep.

As a result of the paused breathing and/or snoring, many sleep apnea sufferers are woken up throughout the night and spend more time in light sleep, rather than deep, restful REM (rapid eye movement) sleep. This chronic sleep deprivation results in daytime sleepiness, and can negatively affect job performance, mood, reflexes, concentration, and it can lead to hypertension, heart disease, and memory problems.

Testing and results of the study

To determine the effect of untreated sleep apnea on driving, the researchers conducted two separate studies. The first was a driving simulation test where 133 patients with untreated sleep apnea and 89 without sleep apnea were asked to “drive” 90 km—about 55 miles.

Various criteria was recorded, including the participants’ ability to complete the driving distance, their time spent in the middle lane, and any participation in an unprovoked crash or a “veer event” crash.

The results of the driving simulation test showed that:

• Patients with untreated sleep apnea were more likely to fail the driving simulation test—24 percent of the sleep apnea patients failed the test, compared to 12 percent of those without sleep apnea.
• In addition, many patients with untreated sleep apnea were unable to complete the test at all, had more unprovoked crashes, and were unable to follow the clear driving instructions given at the beginning of the simulation test.

In the second study, 118 people with untreated sleep apnea and 69 without sleep apnea completed a questionnaire about their driving behavior, and also took the 90 driving test on the simulator.
The results showed that:

• 35 percent of those with untreated sleep apnea admitted to nodding asleep while at the wheel, and 38 percent of this same group failed the driving simulation test.
• By comparison, only 11 percent of people without sleep apnea said they have nodded off while driving, and none of this group failed the simulator test.

Key differences in the reasons for failure

While some people in the control group (those without sleep apnea) also failed the driving simulator test, the researchers noted key differences in why they failed the test:

• 13 people with untreated sleep apnea did not finish the test because they fell asleep or veered completely off the road.
• 5 people with untreated sleep apnea failed because they spent more than 5 percent of the study outside the lane they had been instructed to stay in.

But in the control group, no one failed the simulation for either of these reasons. Again, no one in the “without sleep apnea” group failed the driving simulation due to falling asleep, veering completely off the road, or driving outside the lane.

Dan Smyth of Sleep Apnea Europe noted, "The dangers of untreated sleep apnea and driving are highlighted in both studies. These studies give weight to the need for provision of sufficient resources for early diagnosis and treatment.

While further investigation is needed to examine the reasons for failure of the simulator tests, I acknowledge the researchers for bringing light to this very dangerous side effect of untreated sleep apnea. of sleep apnea, where effective treatment ensures a return to acceptable risk levels for road users."

Are you at risk for sleep apnea?

So how do you know you may have obstructive sleep apnea? Some common symptoms include snoring, paused breathing during sleep and excessive sleepiness during the day. Increased blood pressure is another sign you may have sleep apnea.

While sleep apnea is more common in men, OSA increases in women after age 50. Being overweight may also increase a woman’s risk of having sleep apnea. Menopausal women are three and a half times more likely to get OSA, possible due to reduced amounts of progesterone.

If you experiencing one or more of the above sleep apnea symptoms on a regular basis, see a qualified sleep doctor to get diagnosed and treated properly. There are multiple options and minimally invasive techniques available today to treat your sleep disorder.