Truckers disregarding sleep apnea treatment show greater crash risk
In a study with implications for both trucking companies and policymakers, Roadway Safety Institute researchers have found that non-adherence with employer-mandated sleep apnea treatment increases the risk of serious truck crashes.
"It's well established that left untreated, obstructive sleep apnea is associated with higher crash risk in the general driving population, but relevant data about commercial drivers has been scarce," says Stephen Burks, a professor of economics and management at the University of Minnesota Morris. "Our study examined the first-ever employer-mandated program for diagnosing and treating this dangerous disease among drivers and found a large and statistically significant association between non-adherence with treatment and preventable tractor-trailer crashes."
Obstructive sleep apnea (OSA) is a disease in which the patient's airway closes repeatedly during sleep, causing the brain to partially awaken to resume breathing; this prevents restful sleep, which in turn affects a person's ability to maintain the type of alert attention required for driving. To help prevent crashes associated with OSA, major motor carrier Schneider became the first trucking company to institute a mandatory program to screen, diagnose, and treat this disease among its drivers in 2006; drivers diagnosed with sleep apnea are provided with an auto-adjusting positive airway pressure (APAP) treatment, at no out-of-pocket cost for those enrolled in the firm's employee medical insurance program. Treatment adherence is required for continued employment.
Using the data collected through this employer-mandated program, Burks and his research team set out to identify exactly how risky truckers with untreated OSA are on the road. By comparing the relative crash rates for drivers who followed their OSA treatment plan with drivers who did not, researchers found that the non-adherent drivers had a risk about five times higher than the control group. Even after checking for other factors such as demographic characteristics and job type, they found that the non-adherent group had a significantly higher crash risk than the control group.
"In short, we found that if we followed 1,000 drivers of each type driving for one year, the control and treatment-adherent groups would both have 14 preventable, reportable crashes while the non-adherent group would have 70 such crashes," Burks says.
An employer-mandated OSA program that includes required treatment adherence could improve safety because it effectively sorts the workforce—it retains those drivers who are adherent and safer while filtering out those who are not adherent and much riskier, thereby improving the preventable crash performance of the entire fleet, Burks says.
"Every commercial driver has a screening exam at least every two years to determine their medical fitness to drive, but there is no test given to diagnose sleep apnea—that requires a measurement that takes at least overnight," Burks says. Currently, medical examiners are not required to ask for the extra information to screen for possible sleep apnea in order to decide who should get such a test, and truck drivers know not to say anything about conditions that might jeopardize their driving careers. "As a result, drivers that have been diagnosed with OSA and who are not adherent with treatment can go to work for another company and be back out on the highway with you," Burks says.
The USDOT began an exploratory rulemaking on OSA screening for truck drivers in 2016, but it was withdrawn by the new administration in 2017, Burks notes. "Our study suggests that mandating screening in the commercial vehicle drivers' biennial medical exam is worth revisiting."