Single and Combined Effects of Air, Road, and Rail Traffic Noise on Sleep and Recuperation

TLDR

Traffic noise disrupts sleep and may impair recovery, yet little is known about the single or combined effects of air, road, and rail traffic noise on sleep and recuperation. The authors propose that field studies are needed to validate these laboratory findings in more ecologically valid settings. Using a repeated‑measure polysomnographic laboratory design, 72 healthy adults were exposed to 40, 80, or 120 rail, road, and/or air traffic noise events over 11 consecutive nights, including eight noise‑exposure nights and one noise‑free control night. Objective sleep structure and continuity were only subtly affected, with road noise producing the greatest fragmentation, while subjective sleep quality and recuperation were markedly impaired; cardiac arousals did not habituate, and differences were linked to spectral and temporal noise characteristics, suggesting targets for noise control.

Abstract

Traffic noise disturbs sleep and may impair recuperation. There is limited information on single and combined effects of air, road, and rail traffic noise on sleep and recuperation.Repeated measures.Polysomnographic laboratory study.72 healthy subjects, mean ± standard deviation 40 ± 13 years, range 18-71 years, 32 male.Exposure to 40, 80, or 120 rail, road, and/or air traffic noise events.Subjects were investigated for 11 consecutive nights, which included 8 noise exposure nights and one noise-free control night. Noise effects on sleep structure and continuity were subtle, even in nights with combined exposure, most likely because of habituation and an increase in arousal thresholds both within and across nights. However, cardiac arousals did not habituate across nights. Noise exposure significantly affected subjective assessments of sleep quality and recuperation, whereas objective performance was unaffected, except for a small increase in mean PVT reaction time (+4 ms, adjusted P < 0.05). Road traffic noise led to the strongest changes in sleep structure and continuity, whereas subjective assessments of sleep were worse after nights with air and rail traffic noise exposure. In contrast to daytime annoyance, cortical arousal probabilities and cardiac responses were significantly lower for air than for road and rail traffic noise (all P < 0.0001). These differences were explained by sound pressure level rise time and high frequency (> 3 kHz) noise event components.Road, rail, and air traffic noise differentially affect objective and subjective assessments of sleep. Differences in the degree of noise-induced sleep fragmentation between traffic modes were explained by the specific spectral and temporal composition of noise events, indicating potential targets for active and passive noise control. Field studies are needed to validate our findings in a setting with higher ecologic validity.