Adiponectin is divided into high-molecular-weight (HMW), middle-molecular-weight (MMW) and low-molecular-weight (LMW) types. While HMW adiponectin has been studied by many researchers, the roles of MMW and LMW adiponectin have not yet been sufficiently elucidated. In addition, there are conflicting findings regarding the role of adiponectin in chronic inflammatory diseases, especially asthma. Therefore, we compared patients who suffered episodes of asthma in the past (=asthmatics) with those who did not (=non-asthmatics) in order to investigate the relationship between asthma and HMW, MMW and LMW adiponectin. The subjects in this study included 76 university students. None of the subjects were smokers, on regular medications or seeing a doctor regularly at the time. Fourteen subjects reported past histories of asthma. We also measured and compared the levels of leptin and ghrelin to that of adiponectin, as these hormones are connected with inflammatory conditions. Although the physical data of the asthmatics were similar to those of the non-asthmatics, the levels of ghrelin and all fractions of adiponectin tended to be lower in the asthmatics than in the non-asthmatics. While the levels of MMW and LMW adiponectin in the asthmatics were found to be significantly low, the levels of ghrelin and HMW adiponectin were not clear. According to a multivariate regression analysis of the MMW and LMW adiponectin levels, asthma was found to be more significantly associated with the LMW adiponectin level than age, waist circumference or HDL-C. The results suggest that LMW adiponectin may be associated with episodes of asthma in males.

Numerous studies have determined that lifestyle factors (smoking, drinking, snacking, etc.) and the bedroom environment can influence sleep. We developed a new sleep scale—the 3-Dimensional Sleep Scale (3DSS)—which measures three elements of sleep: phase, quality, and quantity. The purpose of this study is to determine which risk factors of sleep complaints are associated with these sleep elements. Data were obtained from 366 Japanese day workers (302 men and 64 women). Sleep condition was assessed with the 3DSS, and we also assessed various habits within 2 h of going to bed, including smoking, drinking, snacking, caffeine intake, mobile phone use, and working. We also asked about bedroom environmental conditions (noise, lighting, and temperature and humidity). Multivariate logistic regression analysis using the backward selection method (likelihood ratio) was used, with 3DSS scores as the outcome (i.e., over or under the cutoff). The results showed that smoking was associated with significantly greater odds ratio [2.71 (1.65–4.44)] of disordered sleep phase, while lighting as well as temperature and humidity led to greater odds [3.67 (1.55–8.68), 1.93 (1.20–3.11)] of poor sleep quality. Finally, only noise was significantly related to greater odds [1.98 (1.13–3.46)] of low sleep quantity. These findings indicated the various risk factors of sleep complaints could be associated with different sleep elements. This might help in the effective treatment of sleep complaints.

Few studies have examined the relationship between teleworking practices and presenteeism. This study determined the association between teleworking practices and presenteeism among teleworkers in Japan. A cross-sectional online survey was administered to 2687 teleworkers from five companies in Japan, collecting data on demographic variables, teleworking practices, frequency and duration of teleworking, presenteeism, and various lifestyle- and health-related factors. A logistic regression analysis was performed. Teleworkers with full-time employment and less teleworking experience exhibited higher presenteeism rates. Key practices negatively associated with presenteeism included creating a dedicated workspace, chatting with colleagues, and setting daily work goals. Gender differences were significant: for men, additional practices, such as determining their work hours, were beneficial; while for women, chatting with colleagues was particularly important. A sensitivity analysis indicated that specific teleworking practices can mitigate presenteeism. Certain teleworking practices, such as creating a workspace, chatting with colleagues, and setting work goals, were associated with lower presenteeism among teleworkers. These findings highlight the need for organizations to support telework ergonomics, promote social interaction, and encourage goal setting to enhance teleworker productivity and health. Training for employees and supervisors to raise awareness of their own and their subordinates’ health while teleworking is advised.

Despite the serious influence of problematic Internet use on mental health among Japanese adolescents, no randomized clinical trials have investigated universal school-based interventions for this potential health challenge. Therefore, this study aimed to assess the efficacy of a school-based educational program. This two-armed, parallel, cluster-based randomized clinical trial included 5312 students from 13 high schools situated in a mid-sized Japanese city. The students in the intervention arm received 10 weekly standardized sessions, including a combination of information provision and interactive sessions by schoolteachers. The students in the control group followed a standard school curriculum. A generalized estimating equation model was applied to assess the primary (Korean Scale for Internet Addiction [K-scale] score) and secondary (behavioral change status according to changes in the transtheoretical model smartphone addiction score and Internet usage time) outcomes two months after intervention completion. The intention-to-treat analysis included 2597 (97.2%) and 2504 (94.9%) students in the intervention and control groups, respectively. Nevertheless, a significant discrepancy emerged regarding the behavioral change status. Therefore, this school-based program did not improve the Internet or smartphone addiction scores among Japanese adolescents. Further studies are needed to develop appropriate interventions for adolescents.

Objectives: This study aimed to determine that workers’ sleep and labor productivity differ with the telework frequency and that the optimal telework frequency depends on workers’ psychological distress. Methods: A cross-sectional study using an online-based questionnaire was conducted with 2,971 workers employed by Japanese companies from October to December 2021. We used the 6-item Kessler Scale, K6, as a nonspecific psychological distress scale to screen mental health conditions. A score of ≤ 4 was defined as low psychological distress (LPD), and a score of ≥ 5 was defined as high psychological distress (HPD). We used the Athens Insomnia Scale (AIS) as a measure of sleep quality. The Utrecht Work Engagement (UWES) and Work Functioning Impairment (WFun) scales were used as measures of labor productivity. Series of analysis of covariance (ANCOVA) was used for the data analysis. Results: The analysis included 2,013 participants (1,390 men and 623 women; mean age 43.2 years, standard deviation 11.3). Multiple comparison tests showed that among the participants categorized HPD (HPD type), the AIS estimates were lowest in the 1–2 d/wk group, with significant differences between the 0–3 d/m and ≥ 5 d/wk groups. UWES estimates were lowest in the 3–4 d/wk group with significant differences between the participants categorized LPD (LPD type) and HPD type, while no significant differences were observed among the LPD type. The WFun estimates among the LPD type decreased significantly with increasing telework frequency, while no significant differences were observed among the HPD type. Conclusions: The optimal telework frequency for sleep and labor productivity may depend on the workers’ psychological distress. The finding of this study could make a great contribution to occupational health activities and health promotion for teleworkers, which is necessary to make teleworking a sustainable work style.