Good sleep is essential for good health. Lack of sleep is associated with an overall poorer quality of life and higher risk of conditions such as hypertension, diabetes, depression, obesity and cerebrovascular disease. In contrast, getting enough sleep has been linked with reduced mortality risk. One common cause of poor sleep is environmental noise, which has been shown to significantly reduce sleep quality.
The purpose of the Sounds and Sleep study was to assess the efficacy of a digital wellness device, the Bose noise-masking sleepbuds™, at improving sleep quality for participants with self-reported difficulty sleeping due to environmental auditory disruptions, by blocking external noise (passive attenuation) and promoting relaxation with soothing sounds.
Fifty-five people participated in this pre-post efficacy study. Participants were between 21 and 65 years old, and self-identified as light or moderate sleepers with self-reported difficulty falling or staying asleep due to environmental noise. Potential participants were excluded from the study if they had pre-existing sleep disorders such as sleep apnoea, restless leg syndrome or circadian rhythm disorder, or if they reported behaviours or conditions associated with impaired sleep quality, such as excess consumption of caffeine, alcohol or tobacco, or sleep disturbances due to pain, nocturia or menopausal symptoms. Objective sleep-architecture data was obtained through EEG data collected with the Sleep Profiler™ in-home monitor, and subjective participant self-report data on sleep quality was collected through daily and post-intervention surveys. Individuals each participated in the study over 10 consecutive nights, consisting of an initial 3-night baseline period followed by a 4-night adjustment period and a final 3-night intervention period. After adjusting for missing/invalid data, fifty participants were included in the analysis. Primary outcomes were analysed for statistical significance using mixed-effect linear regression and a random intercept for each participant to model repeated measures over time. Exploratory analysis of secondary outcomes was conducted using descriptive statistics and stratified by exposure time.
Use of Bose noise-masking sleepbuds™ was associated with reduced sleep onset latency, as measured both objectively with the Sleep Profiler™ and subjectively through participant self-report. Perceived sleep onset latency when using the Bose noise-masking sleepbuds™, as compared to baseline, was 32.5% reduced (p<0.001, difference in means 7.5 minutes, 95% CI = 22.3% to 41.4% faster), and objectively measured sleep onset latency was 13.3% reduced (p=0.030, difference in means 2.7 minutes, 95% CI = 1.4% to 23.8% faster). Although, on average, there were fewer occurrences of wake after sleep onset and fewer awakenings when using Bose noise-masking sleepbuds™, no statistically significant differences were found. Total sleep time was lower on average when using Bose noise-masking sleepbuds™. Participants reported increased relaxation and better perceived sleep outcomes when wearing Bose noise-masking sleepbuds™, and all participants (100%) reported that Bose noise-masking sleepbuds™ were effective at blocking environmental noise, 86% reported falling asleep more easily, 76% felt it was easier to stay asleep and 82% reported experiencing an overall improvement in sleep quality.
People fell asleep faster when using Bose noise-masking sleepbuds™, both when objectively measured and as subjectively perceived. In addition, people reported positive sleep outcomes when using Bose noise-masking sleepbuds™ versus when sleeping without them. These findings show promise for the use of digital wellness devices in noisy environments to improve sleep quality.