INMA: “Does environmental noise affect sleep in preadolescence?”
Exposure to environmental noise, especially road traffic noise, is an important and growing public health concern. More than 100 million European citizens are exposed to an average daily noise level from road traffic of at least 55 dB, whereas the World Health Organization (WHO) recommends reducing road-traffic noise levels to 53 dB.
Sleep is an essential biological process that serves vital functions, including promotion of neuroplasticity and neural development. Sleep disruption has been related with numerous short- and long-term health consequences. Short-term consequences include increased stress responsivity, cognitive deficits as well as emotional and behavioral problems. Long-term consequences of sleep disruption include hypertension, cardiovascular diseases, and diabetes mellitus type 2. Several studies have linked environmental noise exposure to higher sleep disturbances in adults, but are less conclusive in children. To date, most studies have used parental- or self-reports to characterize sleep, and few studies have included objective measurements to assess sleep quality. Also, previous literature has mostly ignored other noise sources such as railway, aircraft, or industry, which could play a different role in sleep patterns.
The main objective of the study was to determine whether road traffic and multiple noise exposure (i.e. road, railway, aircraft, and industry) could affect sleep in preadolescents, using maternal-reported and wrist-actigraphy data from two birth cohorts in Europe.
A total of 1477 children aged 12 years from the INMA Sabadell (Spain) and the Generation R Study (the Netherlands) were included. Noise levels were modelled at the participants addresses using noise maps created in 2012. Children’s sleep disturbances were reported by mothers through questionnaires for assessing: i) problems with initiating and maintaining sleep, ii) excessive somnolence, and iii) arousal problems (i.e. partial awakening from deep to light sleep, or from sleep to a state of being awake in which the subjects are partially or totally unconscious). Sleep was objectively measured with a wrist accelerometer placed on the non-dominant wrist during 7 days for obtaining the following physiological parameters: total sleep time (i.e., total amount of time asleep during the night, extracting time scored as awake in between), sleep efficiency (i.e., ratio of total sleep time to total time in bed), sleep onset latency (i.e., time a child needs to fall asleep), and wake after sleep onset (i.e., amount of time a child spends awake, starting from the time they fall asleep until the time they become fully awake). Lifestyle and socioeconomic variables were recorded using questionnaires and instruments completed by the parents.
Exposure to road traffic noise was on average 53.2 dB in the Generation R Study and 61.3 dB in the INMA-Sabadell cohort. Results suggest that exposure to noise was related with reduced total sleep time and longer wake after sleep onset in both cohorts. Authors reported no association between noise exposure and maternal-reported sleep disturbances. Results were similar for multiple noise exposure, but most of the association was attributable to road traffic noise as it is the most predominant noise source. Authors say that “although the observed estimates were relatively small, these results might be more meaningful at the population-level due to the high prevalence of exposure to environmental noise”.
Referencia: Pérez-Crespo L, Essers E, Foraster M, Ambrós A, Tiemeier H, Guxens M. Outdoor residential noise exposure and sleep in preadolescents from two European birth cohorts. Environ Res. 2023 Feb 16;225:115502. doi: 10.1016/j.envres.2023.115502. Epub ahead of print
Link al artículo científico: https://doi.org/10.1016/j.envres.2023.115502