Study Objectives: Bedtime procrastination (BP) is defined as going to bed later than intended despite absence of external reasons. This study investigated sleep and psychological factors associated with BP in young adults, and further compared how high and low BP groups spend their time over 24 h and also 3 h prior to bedtime using time use surveys. Methods: Young adults (N = 106) from the community were classified as either high (n = 54) or low (n = 52) BP group based on the Bedtime Procrastination Scale. All participants were asked to complete questionnaires on insomnia, depression, anxiety, stress, and chronotype, in addition to keeping a 7-day sleep diary and completing time use surveys over 48 h. Results: Participants were 61.3% female, mean age 22.7 (±2.89) years old. Individuals in the high BP group reported significantly more depression, anxiety, and insomnia, went to bed later, woke up later, and had more eveningness tendencies compared to the low BP group. Results from the time use surveys revealed that the high BP group spent significantly more time engaging in leisure and social activity with the majority of time spent using media over 24 h compared to the low BP group. Finally, the high BP group spent on average approximately 451% (or 61 min) more time per day on their smartphone 3 h prior to bedtime compared to the low BP group. Conclusions: Our results suggest that BP is negatively associated with sleep and mood, and should be considered a serious health-interfering behavior.

Although the prevalence of cigarette smoking has declined in Western countries over the past few decades, a comparable decline among males has not been observed in Asian countries, especially in South Korea, where approximately 40%-50% of men and 4%-8% of women have been identified as smokers, and there is a pressing need to understand the background of cigarette smoking in these populations. The present study is a narrative review of the research literature on cigarette smoking in South Korea. First, we describe the social, economic, and cultural factors that impact cigarette smoking in South Korea. The paper also reviews the available peer-reviewed literature comprising observational studies and interventional studies, including randomized controlled trials. The extant literature on smoking in Korean Americans is also reviewed. Cigarette smoking in South Korea has been relatively understudied, and this review identifies priority areas for future research, including the use of mobile interventions.

Chung S, et al. J Korean Med Sci. 2021 Nov;36(47):e319. https://doi.org/10.3346/jkms.2021.36.e319

Esports is becoming increasingly professionalized, yet research on performance management is remarkably lacking. The present study aimed to investigate the sleep and mood of professional esports athletes. Participants were 17 professional esports athletes from South Korea (N = 8), Australia (N = 4), and the United States (N = 5) who played first person shooter games (mean age 20 ± 3.5 years, 100% male). All participants wore a wrist-activity monitor for 7–14 days and completed subjective sleep and mood questionnaires. Participants had a median total sleep time of 6.8 h and a sleep efficiency of 86.4% per night. All participants had significantly delayed sleep patterns (median sleep onset 3:43 a.m. and wake time 11:24 a.m.). Participants had a median sleep onset latency of 20.4 min and prolonged wake after sleep onset of 47.9 min. Korean players had significantly higher depression scores compared to the other groups (p < 0.01) and trained longer per day than the Australian or United States teams (13.4 vs. 4.8 vs. 6.1 h, respectively). Depression scores were strongly correlated with number of awakenings, wake after sleep onset, and daily training time (p < 0.05). As the first pilot sleep study in the esports field, this study indicates that esports athletes show delayed sleep patterns and have prolonged wake after sleep onset. These sleep patterns may be associated with mood (depression) and training time. Sleep interventions designed specifically for esports athletes appear warranted.

Study Objectives:Younger children and adolescents are exposed to various smart devices in the modern world, and their use of smart devices is rapidly increasing worldwide. Although smart devices ha...

The general population has reported experiencing anxiety due to the COVID-19 pandemic. This study explored the validity and utility of the Stress and Anxiety to Viral Epidemics-6 items (SAVE-6) scale for measuring the anxiety response of the general population to the viral epidemic. About 1,009 respondents participated in an online survey. Of these, 501 (49.7%) participants were rated as having at least a mild degree of anxiety response to the viral epidemic (SAVE-6 score ≥ 15), while 90 (8.9%) and 69 (6.8%) participants were rated as having moderate degree of depression and anxiety, respectively. The SAVE-6 scale showed a good internal consistency (Cronbach’s alpha = 0.815). Parallel analysis suggested a one-factor structure for the measure. The SAVE-6 scale was found to be a reliable, valid, and useful brief measure that can be applied to the general population.