In a letter to the Federal Motor Carrier Safety Administration, the National Transportation Safety Board recommended that the agency implement a program to identify commercial drivers at high risk for obstructive sleep apnea
, or OSA. The NTSB also recommended that drivers be required to provide evidence that they've been evaluated for OSA and treated if need be.

In addition, the board believes the FMCSA should distribute guidance to commercial drivers, employers and physicians on identifying and treating OSA.

The NTSB cited several transportation crashes involving sleep apnea, including a tractor-trailer driver who collided with a Tennessee Highway Patrol vehicle, killing the state trooper inside. The truck then went across the median and crashed into Chevrolet Blazer, injuring the driver. The driver of the truck had unreported sleep apnea. Other sleep apnea-related accidents that the board cited involved a motorcoach, two airline pilots, and a rail accident.

The NTSB also noted studies on sleep apnea, including one that found that the prevalence of sleep apnea was more than 50 percent in patients with an average body mass index of 40.0. Another study found that 96 percent of male patients with resistant hypertension had unsuspected OSA. A 2002 review of the epidemiology of OSA estimated that roughly 7 percent of adults have at least moderate OSA.

In addition, the letter mentioned a study commissioned by the FMCSA, which reported that 17.6 percent of drivers studied had mild OSA, 5.8 percent had moderate OSA, and 4.7 percent had severe OSA.

To access the NTSB letter, visit www.ntsb.gov/recs/letters/2009/h09_15_16.pdf.