Sleep disorders: a potential role in New Zealand motor vehicle accidents

The potential role of sleep disorders in New Zealand motor vehicle accidents (MVA) has not been systematically studied.

To trial a recruitment method and document the frequency of sleep disorders in drivers attending an emergency department with injury following MVA.

Injured drivers admitted to Wellington Hospital Emergency Department were prospectively recruited by letter and follow-up telephone call. Data from a traffic accident, health and sleep questionnaire and polysomnography were collected and analysed using the SPSS statistical package.

Of 120 eligible drivers, 40 (33%) completed the study protocol. The mean age of participants was 44 +/- 17 years. Non-participants were younger (mean age 33 +/- 14 years, P < 0.01) and more often of Asian or Pacific Island ethnicity (P < 0.01). Twenty-seven (67%) felt unrefreshed on waking and 10 (25%) had an elevated Epworth Sleepiness Score (> 10/24). Six (15%) felt drowsy or fell asleep prior to the accident. Sleep disorders were common (40%): obstructive sleep apnoea 14 (35.9%), periodic limb movements of sleep three (7.7%), sleep restriction (< 6 h sleep on a regular basis) five (12.5%), and insomnia one (2.5%).

Daytime somnolence and sleep disorders were commonly found in drivers attending the Emergency Department after accidents resulting in injury. Driver fatigue and sleep disorders should be considered as a potential contributing factor in New Zealand MVAs. Recruitment of drivers following a MVA via the Emergency Department is challenging. Strategies to improve recruitment are discussed.