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Vibration from freight trains fragments sleep: A polysomnographic study.

Smith MG, Croy I, Hammar O, Persson Waye K - Sci Rep (2016)

Bottom Line: Nocturnal trains in particular are of particular importance since night-time exposure may interfere with sleep.In an experimental polysomnographic laboratory study, 24 young healthy volunteers with normal hearing were exposed to simulated freight pass-bys with vibration amplitudes of 0.7 and 1.4 mm/s either 20 or 36 times during the night.Subjects reported sleep disturbance due to vibration (F(4,92) = 25.9, p < 0.001) and noise (F(4,92) = 25.9, p < 0.001), with the number of trains having an effect only for the 0.7 mm/s condition (p < 0.05).

View Article: PubMed Central - PubMed

Affiliation: Department of Occupational and Environmental Medicine, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden.

ABSTRACT
As the number of freight trains on railway networks increases, so does the potential for vibration exposure in dwellings nearby to freight railway lines. Nocturnal trains in particular are of particular importance since night-time exposure may interfere with sleep. The present work investigates the impact of vibration and noise from night-time freight trains on human sleep. In an experimental polysomnographic laboratory study, 24 young healthy volunteers with normal hearing were exposed to simulated freight pass-bys with vibration amplitudes of 0.7 and 1.4 mm/s either 20 or 36 times during the night. Stronger vibrations were associated with higher probabilities of event-related arousals and awakenings (p < 0.001), and sleep stage changes (p < 0.05). Sleep macrostructure was most affected in high vibration nights with 36 events, with increased wakefulness (p < 0.05), reduced continual slow wave sleep (p < 0.05), earlier awakenings (p < 0.05) and an overall increase in sleep stage changes (p < 0.05). Subjects reported sleep disturbance due to vibration (F(4,92) = 25.9, p < 0.001) and noise (F(4,92) = 25.9, p < 0.001), with the number of trains having an effect only for the 0.7 mm/s condition (p < 0.05). The findings show that combined vibration and noise from railway freight affects the natural rhythm of sleep, but extrapolation of significance for health outcomes should be approached with caution.

No MeSH data available.


Related in: MedlinePlus

Additional probabilities and 95% confidence intervals of arousals (A), awakenings (B), combined EEG arousals and awakenings (C) and sleep stage changes (D) in the experimental nights.
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f2: Additional probabilities and 95% confidence intervals of arousals (A), awakenings (B), combined EEG arousals and awakenings (C) and sleep stage changes (D) in the experimental nights.

Mentions: Applying a 60 s analysis window (see Supplementary Results for rationale), the probability of observing combined EEG reactions (PEEG,ob p < 0.0001) and sleep stage changes (PSSC,ob p < 0.0001) was significantly higher in all exposure nights than in the control night. Figure 2 presents the additional probabilities relative to the baseline as determined in the control condition for arousals (Fig. 2A), awakenings (Fig. 2B), combined EEG reactions (Fig. 2C) and SSCs (Fig. 2D) over the full course of the night. PSSC.additional and PEEG.additional were greater in high vibration nights compared to moderate vibration nights with the same event distribution (p < 0.001 for EEG, see Fig. 2C, p < 0.05 for SSCs, see Fig. 2D). In nights with moderate vibration, PSSC.additional was lower in the 36 event night than the 20 event night. No other significant effects were observed between nights with different numbers of trains.


Vibration from freight trains fragments sleep: A polysomnographic study.

Smith MG, Croy I, Hammar O, Persson Waye K - Sci Rep (2016)

Additional probabilities and 95% confidence intervals of arousals (A), awakenings (B), combined EEG arousals and awakenings (C) and sleep stage changes (D) in the experimental nights.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4835753&req=5

f2: Additional probabilities and 95% confidence intervals of arousals (A), awakenings (B), combined EEG arousals and awakenings (C) and sleep stage changes (D) in the experimental nights.
Mentions: Applying a 60 s analysis window (see Supplementary Results for rationale), the probability of observing combined EEG reactions (PEEG,ob p < 0.0001) and sleep stage changes (PSSC,ob p < 0.0001) was significantly higher in all exposure nights than in the control night. Figure 2 presents the additional probabilities relative to the baseline as determined in the control condition for arousals (Fig. 2A), awakenings (Fig. 2B), combined EEG reactions (Fig. 2C) and SSCs (Fig. 2D) over the full course of the night. PSSC.additional and PEEG.additional were greater in high vibration nights compared to moderate vibration nights with the same event distribution (p < 0.001 for EEG, see Fig. 2C, p < 0.05 for SSCs, see Fig. 2D). In nights with moderate vibration, PSSC.additional was lower in the 36 event night than the 20 event night. No other significant effects were observed between nights with different numbers of trains.

Bottom Line: Nocturnal trains in particular are of particular importance since night-time exposure may interfere with sleep.In an experimental polysomnographic laboratory study, 24 young healthy volunteers with normal hearing were exposed to simulated freight pass-bys with vibration amplitudes of 0.7 and 1.4 mm/s either 20 or 36 times during the night.Subjects reported sleep disturbance due to vibration (F(4,92) = 25.9, p < 0.001) and noise (F(4,92) = 25.9, p < 0.001), with the number of trains having an effect only for the 0.7 mm/s condition (p < 0.05).

View Article: PubMed Central - PubMed

Affiliation: Department of Occupational and Environmental Medicine, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden.

ABSTRACT
As the number of freight trains on railway networks increases, so does the potential for vibration exposure in dwellings nearby to freight railway lines. Nocturnal trains in particular are of particular importance since night-time exposure may interfere with sleep. The present work investigates the impact of vibration and noise from night-time freight trains on human sleep. In an experimental polysomnographic laboratory study, 24 young healthy volunteers with normal hearing were exposed to simulated freight pass-bys with vibration amplitudes of 0.7 and 1.4 mm/s either 20 or 36 times during the night. Stronger vibrations were associated with higher probabilities of event-related arousals and awakenings (p < 0.001), and sleep stage changes (p < 0.05). Sleep macrostructure was most affected in high vibration nights with 36 events, with increased wakefulness (p < 0.05), reduced continual slow wave sleep (p < 0.05), earlier awakenings (p < 0.05) and an overall increase in sleep stage changes (p < 0.05). Subjects reported sleep disturbance due to vibration (F(4,92) = 25.9, p < 0.001) and noise (F(4,92) = 25.9, p < 0.001), with the number of trains having an effect only for the 0.7 mm/s condition (p < 0.05). The findings show that combined vibration and noise from railway freight affects the natural rhythm of sleep, but extrapolation of significance for health outcomes should be approached with caution.

No MeSH data available.


Related in: MedlinePlus