Nonadherence with Employer-Mandated Sleep Apnea Treatment and Increased Risk of Serious Truck Crashes

To evaluate the effect of an employer-mandated obstructive sleep apnea (OSA) program on the risk of serious preventable truck crashes. Data are from the first large-scale, employer-mandated program to screen, diagnose, and monitor OSA treatment adherence in the US trucking industry. A retrospective analysis of cohorts was constructed: polysomnogram-diagnosed drivers (OSA positive n = 1,613, OSA negative n = 403) were matched to control drivers unlikely to have OSA (n = 2,016) on two factors affecting crash risk, experience-at-hire and length of job tenure; tenure was matched on the date of each diagnosed driver's polysomnogram. Auto-adjusting positive airway pressure (APAP) treatment was provided to all cases (i.e. OSA positive drivers); treatment adherence was objectively monitored. Cases were grouped by treatment adherence: “Full Adherence” (n = 682), “Partial Adherence” (n = 571), or “No Adherence” (n = 360). Preventable Department-of-Transportation-reportable crashes/100,000 miles were compared across study subgroups. Robustness was assessed. After the matching date, “No Adherence” cases had a preventable Department of Transportation-reportable crash rate that was fivefold greater (incidence rate ratio = 4.97, 95% confidence interval: 2.09, 10.63) than that of matched controls (0.070 versus 0.014 per 100,000 miles). The crash rate of “Full Adherence” cases was statistically similar to controls (incidence rate ratio = 1.02, 95% confidence interval: 0.48, 2.04; 0.014 per 100,000 miles). Nontreatment-adherent OSA-positive drivers had a fivefold greater risk of serious preventable crashes, but were discharged or quit rapidly, being retained only one-third as long as other subjects. Thus, the mandated program removed risky nontreatment-adherent drivers and retained adherent drivers at the study firm. Current regulations allow nonadherent OSA cases to drive at another firm by keeping their diagnosis private. A commentary on this article appears in this issue on page 961. Limited data from commercial drivers is a major reason for the US Federal Motor Carrier Safety Administration's failure to require screening for obstructive sleep apnea (OSA). We present the results of the first large-scale, employer program to screen, diagnose, and monitor OSA treatment adherence in the US trucking industry. Among drivers in whom OSA was diagnosed through the program, those adherent with employer-provided positive airway pressure treatment had crash risks similar to controls, whereas nonadherent drivers had a fivefold greater preventable crash risk after adjustment for miles driven and driving experience. Therefore, our results strongly support federal OSA regulations for commercial drivers. Future research should improve the calibration of criteria and thresholds for OSA treatment success.