Development of a mobile application to play music combined with heartbeat sounds and its effect on sleep quality in middle-aged adults: An exploratory study

서론: 음악은 생리적 이완과 긍정 정서, 주의 전환을 유도하여 수면 문제를 개선하는데 도움을 주는 것으로 알려져 있다. 선행연구들은 음악 듣기가 수면의 질 향상에 효과가 있으며, 안전하고 비용-효과적인 불면증 치료 방법으로 활용될 수 있다고 보고하였다. 최근에는 심장박동이나 호흡 소리와 같은 바이탈 사운드의 이완 유도 효과가 실험실 연구를 통해 지지되었으나, 수면 문제를 호소하는 개인을 대상으로 바이탈 사운드를 활용한 임상 연구 사례는 보고된 바 없다. 이에 본 연구는 신체적․심리적 이완을 유도하는 심장박동 소리가 결합된 음악 및 이를 재생하는 모바일 어플리케이션(이하 앱)을 개발하고, 중장년기 일반인의 수면 개선을 위한 효과적 활용 방안을 탐색하였다. 방법: 본 연구에서는 먼저 문헌 조사, 예비 연구를 통해 심장박동 소리가 결합된 음악 콘텐츠와 앱을 개발하고, 실제 수면문제를 호소하는 중장년기 성인을 대상으로 이를 적용하기 위한 무작위 대조군 연구를 실시하였다. 연구대상자는 수면과 관련된 불편감을 호소하는 40-68세 일반인 63명으로, 훈련집단에 22명, 비교집단에 19명, 대기집단에 22명이 무작위 배정되었다. 총 4주의 훈련 기간 동안 훈련집단은 심장박동 소리가 결합된 음악을, 비교집단은 오디오북을 일일 약 30-45분씩 듣도록 하였고, 대기집단은 아무런 훈련을 실시하지 않았다. 효과 평가를 위해 훈련 전, 후, 추후(훈련 종료 4주 후) 총 3차례 자기보고식 설문조사를 통해 수면 문제 심각도, 정서적 어려움, 삶의 질을 평가하였고, 웨어러블 기기를 이용해 일일 수면 시간을 측정하였다. 결과: 세 집단의 훈련 전-후 수면 문제 변화를 비교하였을 때, 모든 집단에서 불면증 심각성 척도(ISI), 피츠버그 수면 질 평가(PSQI), PROMIS 수면 장해 척도 단축형 등 주요 수면장애 척도의 총점과 정서 문제 점수가 다소간 감소하였으나 집단 간 통계적으로 의미 있는 차이는 관찰되지 않았다. 하지만 하위 문항으로 평가한 수면장해 지표 중 새벽에 너무 일찍 잠에서 깨는 문제, 주관적 수면의 질은 훈련 집단의 증상 개선 정도가 대기 집단에 비해 유의미하게 큰 것으로 나타났다. 특히 훈련 집단에서 우울 점수가 정상 범위인 대상자들은 훈련을 통한 수면의 질 호전 양상이 훈련 종료 4주 이후에도 유의미하게 지속되었다. 고찰: 심장박동 소리를 결합한 음악 훈련이 오디오북 훈련과 비교하여 훈련 효과에 있어 우위를 보이지는 않았으나, 대기 집단과 비교하였을 때 주관적 수면의 질 등의 수면장해 변인에 있어서는 효과적일 수 있음을 확인하였다. 단, 심한 우울과 같은 공존병리는 훈련의 효과를 떨어뜨릴 수 있으므로, 모바일 기반 자조 치료로 적절한 효과를 기대하기 위해서는 개인의 불면 심각도와 더불어 우울 수준에 대한 사전 선별이 필요함을 제안하였다. 종합하면, 본 연구에서 개발한 심장박동 소리가 결합된 음악 앱은 임상적 수준의 불면증과 공존병리를 지닌 환자 대상의 일차 치료 도구라기보다, 일상생활에서 수면 관련 불편감을 경험하는 일반인을 위한 헬스케어 보조 도구로서 잠재적 활용성이 있다고 판단된다.Introduction: Music often serves as a self-help tool to induce physiological relaxation, a positive state of mind, and distraction responses in individuals who experience sleep difficulties. Previous studies have reported the positive effects of music on sleep quality and quality of life in individuals with poor sleep and support the use of music as a safe and cost-effective sleeping aid. A recent laboratory study suggested that physiological sounds, including heartbeat (HB) or respiratory sounds may induce relaxation. However, no clinical study has focused on the effects of these sounds in individuals with sleep difficulties. In this study, we developed sleep-inducing music combined with HBs to produce physical and psychological relaxation, as well as a musical mobile application to verify the efficacy of music combined with HBs in middle-aged adults with sleep difficulties. Methods: The study included 63 individuals aged 40–68 years, with sleep difficulties, who were randomized into a music combined with HB intervention (n = 22), an audiobook control (n = 19), and a waitlist control group (n = 22). The intervention group listened to music combined with HBs, and the control group listened to audiobooks for 30–45 min every night. The waitlist control group received no intervention. Using self-administered questionnaires, all subjects were evaluated on three occasions as follows: pre-intervention, post-intervention, and 4 weeks post-intervention for follow-up regarding sleep quality, emotional difficulties, and quality of life. Additionally, we used a wearable device (smart watch) to evaluate objective measures of sleep. Results: We observed no significant effects of music combined with HB on insomnia symptoms (evaluated using the Insomnia Severity Index [ISI], Pittsburgh Sleep Quality Index [PSQI], and the DSM5-PROMIS Sleep scale) and represented as the group × time interaction, although slight reduction in insomnia severity was observed in the two experimental groups. With regard to secondary outcomes, we observed no changes in depression, anxiety, and quality of life. However, among the ISI and PSQI sub-items, symptoms of early morning awakening and subjective sleep quality were significantly improved in the music combined with HB intervention than in the waitlist group. Specifically, intervention-induced improved sleep quality persisted even 4 weeks after intervention in individuals without severe depression. Conclusion: Compared with the waitlist group, the music combined with HB group showed reduced insomnia symptoms, such as early morning awakening and also better subjective sleep quality; however, this approach was not shown to be superior to audiobooks as an effective sleep-inducing intervention. Comorbidities, such as severe depression may reduce the effectiveness of the mobile app-based music intervention for insomnia. We conclude that music combined with HB may potentially be useful as a health care self-help tool for individuals with subclinical levels of insomnia or temporary sleep disturbances, as opposed to being a primary treatment modality for patients with clinical-level insomnia and comorbid psychiatric disorders.Ⅰ. 서론 1 Ⅱ. 방법 7 Ⅲ. 결과 23 Ⅳ. 고찰 42 Ⅴ. 결론 52 참고문헌 53 ABSTRACT 62박

Effects of pleasant sound on overnight sleep condition : A crossover randomized study

It is desirable to improve sleep quality since poor sleep results in decreases in work productivity and increases in risks of lifestyle-related diseases. Sleep spindles in sleep EEG are waveforms that characterize non-REM sleep Stage 2 (Stage N2). Music therapy has been adopted as a non-pharmacological therapy for sleep quality improvement; however, few studies mention the relationship between music during sleep and spindles. We conducted a crossover randomized study to investigate music\u27s effects on spindles and sleep parameters. Polysomnography (PSG) was performed on 12 adult males with sleep difficulties over three nights, during which they were exposed to three different acoustic environments–silent, white noise, and pleasant sounds–throughout the night, in a crossover randomized setting. Half of the participants with large WASO were defined as the sleep maintenance difficulty group. We investigated whether pleasant sounds shortened sleep onset latency (SOL) and increased the number of spindles (SN) and spindle density (SD) compared to white noise, using silent as the reference. The spindles were detected using the previously reported automatic spindle detection algorithm. After one patient was excluded due to data corruption, a total of 11 participants, including the sleep maintenance difficulty group (n = 5), were analyzed. For all participants, SOL was not significantly shorter with pleasant sound than with white noise (p = 0.683); for the sleep maintenance difficulty group, SOL tended to be shorter with pleasant sound than with white noise (p = 0.060). Compared to white noise, the SN increased in pleasant sound for 7 of 11 (4 of 5 in the sleep maintenance difficulty group), and SD increased for 5 of 11 (3 of 5 in the sleep maintenance difficulty group). The results suggest that all-night background sound exposure may affect SN and SD. Future research should investigate whether background sound exposure reduces sleep-related distress, achieves sound sleep, or improves daytime psychomotor function