Brain Sleep Co., Ltd. (Headquarters: Chiyoda-ku, Tokyo; Representative Director: Kosuke Michibata; hereinafter "Brain Sleep") conducted its "Sleep Deviation Value" 2021 survey, following up on the 2020 edition. This survey targeted 10,000 individuals across Japan's 47 prefectures (allocated by gender, age, and prefecture), investigating not only direct indicators of individual sleep habits and sleep status, but also productivity, stress levels, and the risk of sleep apnea syndrome (SAS). Moving forward, we will utilize the results of this survey to undertake various activities aimed at resolving sleep issues, especially in light of current circumstances where sleep is often unstable. [Survey Result Summary] Brain Sleep Co. has been developing its "Sleep Deviation Value®" based on various sleep metrics, aiming to understand the actual sleep conditions of Japanese people and to expand its health management services for corporate employees. This year, the 2021 edition of the Sleep Deviation Value was measured, and the following five new characteristics of Japanese sleep were identified: ① Changes in average sleep duration in Japan ② Relationship between frequency of remote work and sleep quality ③ Relationship between immunity and sleep—Sleep Deviation Value by symptom (cold, flu, new coronavirus) ④ Trends in Sleep Deviation Value by industry and age group ⑤ Sleep Deviation Value ranking by prefecture Average Sleep Duration in Japan: Sleep Debt, which was showing signs of collapse, is now improving According to Brain Sleep's previous year's survey, the average sleep duration in Japan was 6 hours and 27 minutes. This was 55 minutes shorter than the OECD data, which identified Japan as having the shortest sleep duration globally. This year's survey revealed that the average sleep duration in Japan is 6 hours and 43 minutes, an increase of 16 minutes from last year. While Japan's sleep duration has taken a significant step toward improvement, the average sleep duration for OECD member countries is 8 hours and 25 minutes. Compared to Japan's average sleep duration this year, there is still a difference of 1 hour and 42 minutes. Furthermore, only 40% of the population exceeded 7 hours, which is the recommended minimum sleep duration. Brain Sleep will continue to actively disseminate information and educate the public on the importance of securing a minimum amount of sleep, with the aim of further extending the average sleep duration in Japan. Relationship between Remote Work and Sleep Quality: Irregular work styles may lead to a decline in sleep quality The COVID-19 pandemic brought about significant changes in people's lives, and working styles were no exception, with the rapid spread of "remote work" as a new mode of employment being a major feature. A survey conducted by Brain Sleep in April 2020 revealed that the expansion of remote work due to the COVID-19 pandemic led to a general shift towards a later, night-owl lifestyle, disrupting daily and sleep rhythms, and resulting in a decline in sleep quality. However, this current survey found new trends in sleep quality related to "remote work." Analyzing the relationship between the presence/frequency of remote work and sleep quality, it was found that the sleep quality of individuals who "work remotely almost every day" and those who "never work remotely" was significantly higher than that of individuals with other work styles. Notably, the lowest sleep quality was observed among those who "work remotely once or twice a week." This suggests that the consistency of one's daily rhythm, rather than the presence or absence of remote work itself, is more crucial for sleep quality. * Error bars indicate standard error Immunity and Sleep Relationship – Sleep Deviation Value by Symptom (Cold, Flu, Novel Coronavirus) As discussed in the previous section, the novel coronavirus has raged across the globe since 2020, drastically altering people's lifestyles and significantly impacting sleep. On the other hand, this survey revealed that differences in people's sleep states may be strongly related to changes in their physical condition during the pandemic. Comparing the Sleep Deviation Values between people who experienced poor physical health due to a cold, flu, or novel coronavirus between January 2020 and the end of January 2021, and those who did not, the Sleep Deviation Value was significantly lower for those who experienced poor physical health. In particular, the Sleep Deviation Value was exceptionally low for those who suspected they had the novel coronavirus, especially among those who underwent hotel recuperation. While this Sleep Deviation Value only measures current values and does not indicate a causal relationship between poor physical health and Sleep Deviation Value over the past year, it is believed that individuals who experienced poor physical health or felt unwell had reduced immunity, and this may have led to a lower Sleep Deviation Value due to underlying sleep problems. Trends in Sleep Deviation Value by Industry and Age Group We categorized the survey participants by industry and age group and examined the average Sleep Deviation Value for each category. Focusing on specific age groups, only one industry had a deviation value above 50 for individuals in their 20s, while all other industries fell below the average deviation value of 50. Conversely, for individuals in their 50s and 60s, all but one industry exceeded the average. Looking at the average values across all age groups by industry, the average Sleep Deviation Value for individuals in the "Mass Media and Advertising" industry was 47.89, the lowest among all industries. It was also found that individuals in the "Trading Company" industry, which often involves time differences, had the second-lowest values after "Mass Media and Advertising." It is also noteworthy that there was a significant difference in the Sleep Deviation Value for "Mass Media and Advertising" across generations. While the Sleep Deviation Value for those in their 50s and 60s in "Mass Media and Advertising" was 52.63, the highest among all categories, the Sleep Deviation Values for those in their 20s and 30s-40s were 46.58 and 46.76 respectively, making them the lowest Sleep Deviation Values among all categories. Some industries necessitate night shifts or work schedules that reverse day and night, making it difficult for individuals to obtain high-quality sleep, inevitably leading to a daily accumulation of sleep debt. Furthermore, the COVID-19 pandemic likely forced significant changes in working styles for certain industries, and it is believed that individuals in these industries have experienced a substantial impact on their sleep deviation values. We plan to conduct further detailed analysis on these points to clarify the impact on different occupations. Sleep Deviation Value Prefecture Ranking: 1st Mie Prefecture, 47th Tokushima Prefecture As in last year's results, there was no significant difference in the Sleep Deviation Values between the 1st and 47th prefectures (1st Mie Prefecture at 51.16 / 47th Tokushima Prefecture at 48.47), indicating that Japan's sleep issues are nationwide. A general characteristic of Japan is that sleep duration has increased in 46 out of 47 prefectures. However, sleep habits, which contribute to sleep quality, have worsened in 29 prefectures, suggesting that pre-sleep routines may have been disrupted due to the impact of the new coronavirus. Looking at the prefectural breakdown, Mie Prefecture, ranked 1st nationwide, showed improvement in all components that make up the Sleep Deviation Value compared to last year, particularly in sleep habits where it scored higher than other prefectures. On the other hand, Tokushima Prefecture, which ranked last, showed an increase in sleep duration, but all other categories were within the bottom 5. In particular, it ranked last in both sleep quality and daytime performance (productivity). Sleep Deviation Value® Survey Results Page https://brain-sleep.com/sleep-deviation/research2021/ Brain Sleep can provide various information regarding this survey. Comment by Seiji Nishino / Founder of Brain Sleep, Author of "Stanford's Best Sleep" Following the previous year's survey, several interesting results have emerged. The worst sleep quality was observed in those who "work remotely once or twice a week." The fact that those who work remotely almost every day and those who never work remotely had good sleep quality suggests that a regular lifestyle is indispensable for securing sleep quality, and that those who work remotely irregularly may have found it difficult to maintain their daily rhythm. Furthermore, in relation to infectious diseases such as the novel coronavirus and influenza, the Sleep Deviation Value was particularly low for those who experienced poor physical health, those who suspected they had the novel coronavirus, and among them, those who underwent hotel recuperation. In the United States, in particular, even before the novel coronavirus infection, seasonal influenza caused 20,000 to 60,000 deaths annually, and in relation to countermeasures, it has been emphasized that sufficient and good quality sleep prevents colds and influenza infections. It is interesting that similar results were obtained in Japan this time, and it is believed that during the COVID-19 pandemic, it is especially important to maintain a regular lifestyle, maintain daily rhythm, and obtain good quality sleep to boost immunity. Even if vaccination has begun, this mindset remains equally important, and even if vaccinated against the novel coronavirus, insufficient sleep can make it difficult to form antibodies, potentially leading to inadequate infection prevention. What is Sleep Deviation Value®? When evaluating sleep, the focus often falls solely on simple quantitative data such as sleep duration. However, Brain Sleep believes it is crucial to assess sleep from a more multi-faceted and comprehensive perspective. To that end, we developed a set of questions that quantify subjective sleep evaluation from a broad viewpoint, including self-reported symptoms and sleep habits. Furthermore, by converting this into a "deviation value," a concept familiar to Japanese people, we established a system that allows for understanding one's relative sleep status within the overall Japanese population. This is the "Sleep Deviation Value®." Currently, in collaboration with NTT East as an innovation partner, we are developing "Sleep Deviation Value for Biz," a health management service for corporations. This service visualizes "engagement" with the company based on employees' "sleep" and allows companies to discover previously unrecognized issues by comparing their data with the national Sleep Deviation Value, thereby improving presenteeism. Survey Overview Survey method: Web survey Target region: Nationwide Target audience: Men and women Sample size: n=10,000ss Survey period: January 2021 *For comparisons of Sleep Deviation Values and scores between groups, a t-test was conducted, and a significance level of 5% or less was determined to be a statistically significant difference and recorded. *The survey was conducted with some changes in target participants and survey items compared to last year.
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