Implementation Rate of Physical Rehabilitation in Neonatal Intensive Care Units in Japan: A Retrospective Observational Study.

Background and Objective: The benefits of physical rehabilitation for very-low-birth-weight infants (VLBWI) have been reported in previous studies; however, the implementation rate of physical rehabilitation in this population remains to be clarified. This study aimed to examine the implementation rate of physical rehabilitation among VLBWI admitted to the neonatal intensive care unit (NICU) using real-world data. Material and Methods: This observational study obtained data from a nationwide administrative database associated with the diagnostic procedure combination (DPC) system in Japan (2014-2019). The participants were 30,464 infants admitted to the NICU between 2014 and 2019. The overall NICU physical rehabilitation rates and background factors of the participants were examined. Results: The overall physical rehabilitation rate in NICUs was 18%. Infants born at <28 weeks of age and extremely low birth weight infants (ELBWI) were more likely to receive physical rehabilitation interventions. The length of stay at the NICU and hospital, as well as the rate of discharge, were higher in patients who received physical rehabilitation than those in infants who did not. Conclusions: One-fifth of all patients admitted to the NICU received physical rehabilitation interventions. Extremely preterm infants and ELBWI were more likely to receive physical rehabilitation interventions. We need to consider ways to increase physical rehabilitation intervention rates in the NICU.

Early surgical treatment using regional clinical pathways to reduce the length of postoperative hospital stay in hip fracture patients: A retrospective analysis using the Japanese Diagnosis Procedure Combination database.

Hip fracture is a common injury in older adults; however, the optimal timing of surgical treatment remains undetermined in Japan. Therefore, this retrospective study aimed to ascertain the rate of early surgery among hip fracture patients and investigate its effectiveness, along with "regional clinical pathways" (patient plan of care devised by Japanese clinicians), in reducing the length of hospital stay (LOS) postoperatively. We hypothesized that performing early surgery along with a regional clinical pathway is effective to reduce the postoperative LOS and complications among hip fracture patients. We examined the data of patients diagnosed with femoral neck and peritrochanteric fractures retrieved from the Japanese Diagnosis Procedure Combination database between April 2016 and March 2018. Patients were divided into the early (43,928, 34%; surgery within 2 days of admission) and delayed (84,237, 66%; surgery after 2 days of admission) surgery groups. The difference in postoperative LOS between the two groups was 3 days (early vs. delayed: 29 days vs. 32 days). The early surgery group had more cases of intertrochanteric fractures (57% vs. 43%) and internal fixation (74% vs. 55%) than did the delayed surgery group. In contrast, the delayed surgery group had more cases of femoral neck fractures (43% vs. 57%) and bipolar hip arthroplasty (25% vs. 42%) or total hip arthroplasty (1.2% vs. 3.0%). Moreover, the early surgery group showed a lower incidence of complications, except anemia (12% vs. 8.8%). Logistic regression analysis using the adjusted model revealed that early surgery and implementation of regional clinical pathways reduced LOS by 2.58 and 8.06 days, respectively (p<0.001). Early surgery and implementation of regional clinical pathways for hip fracture patients are effective in reducing postoperative LOS, allowing regional clinical pathways to have a greater impact. These findings will help acute care providers when treating hip fracture patients.

Prevalent morphometric vertebral fractures as a risk factor for subsequent clinical vertebral fractures after shortfusion surgery in older Japanese women with degenerative spondylolisthesis.

STUDY DESIGN: A retrospective cohort study using the Kaplan-Meier method with propensity-score matching. PURPOSE: To evaluate whether the presence of prevalent morphometric vertebral fractures (VFs) poses a risk for subsequent clinical VFs after short-fusion surgery in women aged ≥60 years with degenerative spondylolisthesis. OVERVIEW OF LITERATURE: VFs are common osteoporotic fractures and are associated with a low quality of life. Subsequent VFs are a complication of instrumented fusion in patients with degenerative lumbar disorders. Thus, risk factors for subsequent VFs after fusion surgery must be analyzed. Population-based studies have suggested that prevalent morphometric VFs led to a higher incidence of subsequent VFs in postmenopausal women; however, no studies have investigated whether prevalent morphometric VFs are a risk factor for subsequent VFs after fusion surgery in patients with degenerative spondylolisthesis. METHODS: The study enrolled a total of 237 older female patients: 50 and 187 patients had prevalent morphometric VFs (VF [+] group) and nonprevalent morphometric VFs (VF [-] group), respectively. The time to subsequent clinical VFs after fusion surgery was compared between the two groups using the Kaplan-Meier method. Moreover, 40 and 80 patients in the VF (+) and VF (-) groups, respectively, were analyzed and matched by propensity scores for age, follow-up duration, surgical procedure, number of fused segments, body mass index, and number of patients treated for osteoporosis. RESULTS: Kaplan-Meier analysis indicated that the VF (+) group had a higher incidence of subsequent clinical VFs than the VF (-) group, and Cox regression analysis showed that the presence of prevalent morphometric VFs was an independent risk factor for subsequent clinical VFs before matching. Kaplan-Meier analysis demonstrated comparable results after matching. CONCLUSIONS: The presence of prevalent morphometric VFs may be a risk factor for subsequent clinical VFs in older women with degenerative spondylolisthesis who underwent short-fusion surgery.

Association between hospital case volume and maternal adverse events in patients with placental abruption: An analysis using a Japanese national inpatient database.

OBJECTIVE: To clarify the relationship between the prognosis of patients with placental abruption (PA) and the healthcare delivery system using data from a large national inpatient database in Japan. METHODS: Using the Diagnosis Procedure Combination database, we conducted a retrospective cohort study with the data of patients in almost 1000 hospitals with the primary diagnosis of PA who were hospitalized from April 2014 to March 2021. We divided the hospitals into four groups based on the number of deliveries per month. We performed multilevel logistic regression analysis to analyze the relationship between hospital case volume and maternal end-organ injury (MEOI). RESULTS: Altogether, 8222 patients were included for analysis; among whom, 3575 (44%) were transferred by ambulance. MEOI was noted in 977 patients (12%) with no obvious difference by hospital case volume. Ambulance transfer, age, gestational weeks at admission, delivery on the first day of hospitalization, and history of eclampsia were significantly associated with a higher incidence of MEOI, but the hospital case volume was not. CONCLUSION: Using a Japanese administrative database, our study shows that hospital case volume was not significantly associated with the severity of maternal illness among patients with PA.

Analyzing attempt and success factors for amputated digit replantation in Japan using the diagnosis procedure combination database.

The number of amputated finger replantation has declined in the USA and Germany in recent years; however, there have been no reports on recent trends in Japan. We examined the current practices, attempts, and success factors of digit replantation in Japan. We hypothesized that the rates of digit replantation and success rates were consistently standardized in Japan. The diagnosis procedure combination database was used to analyze 14004 cases from April 2014 to March 2020, excluding multiple-digit amputations, thus focusing on 13484 patients. We evaluated replantation success rates and identified factors influencing replantation decisions using multiple logistic regression analysis. The key findings included a higher frequency of replantation in thumb cases and surgeries during overtime hours, on Sundays, and in educational institutions. Success rates were notably higher for thumb replantations and patients under 20 years of age. Patients over 65 years of age treated with urokinase showed higher failure rates, unrelated to regional or hospital case volumes. The number of amputated digit replantation surgeries in Japan was high during overtime hours, on Sundays, and in educational institutions. Region, hospital type, and hospital case volume were not associated with a low success rate across Japan.

Incidence of coronary heart disease among remote workers: a nationwide web-based cohort study.

Coronary heart disease (CHD) risk is influenced by socioeconomic status-related parameters, particularly occupation. We investigated occupational gaps in CHD risk and how the introduction of remote work moderated the observed occupational differences in CHD risk during the coronavirus disease 2019 pandemic in Japan. Data from a web-based, nationwide cohort study, comprising 17,640 workers (aged 20-65 years) with baseline data from December 2020, were analyzed. Participants were grouped by occupation as upper-level nonmanual workers (managers/professionals) and others (reference group). The primary outcome was CHD (angina pectoris/myocardial infarction) onset retrospectively confirmed at the 1-year follow-up survey. Upper-level nonmanual workers exhibited a higher CHD incidence than others (2.3% vs. 1.7%). This association was pronounced in the younger (20-49 years) population, with a significant CHD risk (adjusted risk ratio = 1.88). Upper-level nonmanual workers exhibited nearly 15% higher remote work prevalence, with a significant remote work-related CHD risk (adjusted risk ratio = 1.92). The mediating effects of remote work explained an overall disparity of 32% among the younger population. Occupational gaps in CHD incidence in Japan differ from those in Western countries, where upper-level nonmanual workers have lower cardiovascular risk. In Japan, remote work can mediate CHD risk in the younger population of upper-level nonmanual workers.

A prospective cohort study of presenteeism and increased risk of unemployment among Japanese workers during the COVID-19 pandemic.

OBJECTIVES: Presenteeism adversely affects workers' quality of life, leading to further deterioration of their health and affecting their ability to continue working. Unemployment is one of the most serious consequences for workers experiencing presenteeism. A worker's ability to work depends on the degree of mismatch between their health status and job demands and work factors. The COVID-19 pandemic has affected workers' experiences of presenteeism as well as their employment status. We examined the association between presenteeism and risk of job resignations and unemployment among Japanese workers during the COVID-19 pandemic. METHODS: A prospective study of 27 036 internet monitors was conducted, starting in December 2020, with 18 560 (68.7%) participating in the follow-up by December 2021. The Work Functioning Impairment Scale (WFun) was used to measure the degree of work function impairment. RESULTS: The group with the highest WFun scores had higher odds ratios (ORs) for both retirement and unemployment for health reasons than the group with the lowest WFun scores. ORs were 2.99 (95% CI, 2.48-3.62; P < .001) and 1.82 (95% CI, 1.65-2.00; P < .001), respectively. CONCLUSIONS: Workers with work functioning impairment are at increased risk of resignation or unemployment. Management strategies for workers with work functioning impairment are needed to reduce their disadvantages in employment.

Epidemiologic evaluation of pulmonary paragonimiasis in Japan using a Japanese nationwide administrative database.

BACKGROUND: Paragonimiasis is a parasitic disease primarily contracted through consumption of undercooked freshwater crustaceans or wild boar meat. Large-scale nationwide epidemiological data on paragonimiasis are lacking. In this study, we aimed to investigate the nationwide epidemiology of hospitalized patients with paragonimiasis in Japan using a comprehensive nationwide Japanese administrative database. METHODS: We evaluated the Japanese Diagnosis Procedure Combination (DPC) data of patients diagnosed with pulmonary paragonimiasis between April 1, 2012 and March 30, 2020. The patients' address and information, including age, sex, treatment (medication: praziquantel; surgery: open thoracotomy or intracranial mass extirpation), Japan coma scale, comorbidities, and length of hospital stay, were extracted. RESULTS: Of the 49.6 million hospitalized patients, data were extracted on 73 patients with paragonimiasis, of whom 36 were male and 37 were female. The mean age was 49.7 years and the mean length of stay was 12.5 days. The most frequent comorbidity was pleural effusion (31.5 %), followed by pneumothorax (13.7 %). The sites of ectopic paragonimiasis in organs other than the lung included the liver (5.5 %), skin (4.1 %), and brain (2.7 %). Geographically, most patients were from the Kyushu region (54.8 %), followed by the Kanto region (22.0 %). Fukuoka Prefecture had the highest number of patients (22.0 %) by prefecture. During the study period, an average of 9.1 patients/year were hospitalized with lung paragonimiasis in Japan. CONCLUSION: Paragonimiasis has not completely disappeared in Japan; thus, physicians should be aware of paragonimiasis in the Kyushu region, especially in the Fukuoka Prefecture.

Relationship Between Infection or Close Contact With COVID-19 and Workplace Mistreatment Among Japanese Workers: A Cross-sectional Study.

OBJECTIVE: Discriminatory treatment against those with emerging infection is a long-standing problem. The present study investigates whether workers infected or in close contact with COVID-19 were susceptible to workplace mistreatment during the pandemic in Japan. METHODS: This Internet-based cross-sectional study analyzed a total of 18,170 workers aged 20 to 60 years in Japan in December 2020. Odds ratios (ORs) for workplace mistreatment were estimated. RESULTS: For workers with close contact or infection, ORs for workplace mistreatment in a model adjusted for socioeconomic factors were 7.64 (95% CI: 5.52-10.6, P < 0.001) and 10.7 (95% CI: 8.44-13.6, P < 0.001), respectively. CONCLUSIONS: Workers with infection or close contact were significantly more likely to experience workplace mistreatment. Actions against workplace mistreatment for workers with emerging infection are still required.

Sociodemographic factors affecting not receiving COVID-19 vaccine in Japan among people who originally intended to vaccinate: a prospective cohort study.

Objective: Vaccine hesitancy is a major issue for acquiring herd immunity. However, some individuals may go unvaccinated owing to inhibitory factors other than vaccine hesitancy. If there is even a small number of such people, support is needed for equitable vaccine distribution and acquiring herd immunity. We investigated sociodemographic factors that affected not undergoing COVID-19 vaccination in Japan among individuals who had strong intention to vaccinate before beginning the vaccination. Methods: We conducted this prospective cohort study on workers aged 20-65 years from December 2020 (baseline), to December 2021 using a self-administered questionnaire survey. There were 27,036 participants at baseline and 18,560 at follow-up. We included 6,955 participants who answered yes to this question at baseline: "Would you like to receive a COVID-19 vaccine as soon as it becomes available?" We applied multilevel logistic regression analyses to examine the association between sociodemographic factors and being unvaccinated at follow-up. Results: In all, 289 participants (4.2%) went unvaccinated. The odds ratios (ORs) for being unvaccinated were significantly higher for participants aged 30-39 and 40-49 than those aged 60-65 years. Being divorced, widowed, or single, having low income, and having COVID-19 infection experience also had higher ORs. Discussion: We found that some participants who initially had strong intention to vaccinate may have gone unvaccinated owing to vaccine side effects and the financial impact of absenteeism due to side effects. It is necessary to provide information repeatedly about the need for vaccination as well as social support to ensure that those who intend to vaccinate are able to do so when aiming for acquiring herd immunity through vaccination against COVID-19 as well as other potential infection pandemics in the future.

The Current Status of Suicide and Medical Care System in Japan: An Analysis of 81,407 Patients Using the Diagnosis Procedure Combination Database.

Japan has a high suicide mortality rate compared to other developed countries. To reduce suicide mortality in Japan, it is important to systematically analyze factors related to death of patients with suicide attempt. This study aimed to analyze the characteristics of patients with suicide attempt, and the factors related to their death using the Diagnosis Procedure Combination (DPC) data- a nationally representative inpatient database. We collected 81,407 cases of suicide attempt from 2016 to 2018 from DPC data and performed a multilevel logistic analysis of factors associated with death discharges. The analysis results showed that patients who received psychiatric liaison care had a lower mortality rate, but only 0.6% of surviving patients received psychiatric liaison care after admission. The odds ratio (OR) of death was high for hanging (28.86; p < 0.001) and jumping (16.28; p < 0.001), compared to wrist cutting. Patients without a psychiatric diagnosis were more likely to choose means such as hanging (14.1%) than those with a psychiatric disorder. The weekend cases had a higher OR of death than weekday (Wednesday as reference) cases (Friday 1.14, p = 0.011; Saturday 1.60, p < 0.001; Sunday 1.67, p < 0.001). Based on these findings, we suggest that improving the availability and quality of psychiatric care in acute care hospitals and primary care settings, as well as enhancing the emergency department system on weekends, could help reduce the mortality of suicide attempts.

Evaluation of the Effectiveness and Use of Anti-Methicillin-Resistant Staphylococcus aureus Agents for Aspiration Pneumonia in Older Patients Using a Nationwide Japanese Administrative Database.

Studies indicated potential harm from empirical broad-spectrum therapy. A recent study of hospitalizations for community-acquired pneumonia suggested that empirical anti-methicillin-resistant Staphylococcus aureus (MRSA) therapy was associated with an increased risk of death and other complications. However, limited evidence supports empirical anti-MRSA therapy for older patients with aspiration pneumonia. In a nationwide Japanese database, patients aged ≥65 years on admission with aspiration pneumonia were analyzed. Patients were divided based on presence of respiratory failure and further sub-categorized based on their condition within 3 days of hospital admission, either receiving a combination of anti-MRSA agents and other antibiotics, or not using MRSA agents. An inverse probability weighting method with estimated propensity scores was used. Out of 81,306 eligible patients, 55,098 had respiratory failure, and 26,208 did not. In the group with and without respiratory failure, 0.93% and 0.42% of the patients, respectively, received anti-MRSA agents. In patients with respiratory failure, in-hospital mortality (31.38% vs. 19.03%, p < 0.001), 30-day mortality, and 90-day mortality were significantly higher, and oxygen administration length was significantly longer in the anti-MRSA agent combination group. Anti-MRSA agent combination use did not improve the outcomes in older patients with aspiration pneumonia and respiratory failure, and should be carefully and comprehensively considered.

Clinical characteristics in patients with non-alcoholic steatohepatitis in Japan: a case-control study using a 5-year large-scale claims database.

OBJECTIVES: To examine the clinical characteristics of patients with non-alcoholic steatohepatitis (NASH) and associated comorbidities. DESIGN: A case-control study using the national health insurance and the long-term elderly health insurance claims database. SETTING: Eligible patients diagnosed with NASH (ICD-10 K-75.8, other inflammatory liver disease or K-76.0, other fatty liver) between April 2015 and March 2020 were included. PARTICIPANTS: Patients who met the diagnostic definitions for NASH (n=545) were matched with non-NASH controls (n=185 264) and randomly selected according to sex, birth year and residential area. INTERVENTIONS: No interventions were made. PRIMARY AND SECONDARY OUTCOME MEASURES: ORs were estimated for the relationship between patient background, such as age and sex, body mass index (BMI), NASH-related comorbidities and lifestyle-related diseases. RESULTS: In total, 545 patients with NASH (38.3% men) and 185 264 non-NASH controls (43.2% men) were identified, with median ages of 68 (IQR 63.0-75.0) and 65 (IQR 44.0-74.0) years, respectively. BMI was significantly higher in patients with NASH than in controls (25.8 kg/m2 vs 22.9 kg/m2, p<0.001). The proportions of women, patients with hypertension, patients with dyslipidaemia and patients with type 2 diabetes were higher in the NASH group. In addition, NASH was associated with an increased risk of hepatic cirrhosis (OR 28.81 (95% CI 21.79 to 38.08)), followed by liver cancer (OR 18.38 (95% CI 12.56 to 26.89)). There was no significant association between NASH and risk for depression (OR 1.11 (95% CI 0.87 to 1.41)), insomnia (OR 1.12 (95% CI 0.94 to 1.34)) or chronic kidney diseases (OR 0.81 (95% CI 0.58 to 1.12)). CONCLUSIONS: In the daily medical care of patients, it is necessary to consider sex and age differences and to pay close attention to the risk of liver cancer, as well as other lifestyle-related comorbidities associated with NASH.

Impact of Administering Intravenous Azithromycin within 7 Days of Hospitalization for Influenza Virus Pneumonia: A Propensity Score Analysis Using a Nationwide Administrative Database.

The potential antimicrobial and anti-inflammatory effectiveness of azithromycin against severe influenza is yet unclear. We retrospectively investigated the effect of intravenous azithromycin administration within 7 days of hospitalization in patients with influenza virus pneumonia and respiratory failure. Using Japan's national administrative database, we enrolled and classified 5066 patients with influenza virus pneumonia into severe, moderate, and mild groups based on their respiratory status within 7 days of hospitalization. The primary endpoints were total, 30-day, and 90-day mortality rates. The secondary endpoints were the duration of intensive-care unit management, invasive mechanical ventilation, and hospital stay. The inverse probability of the treatment weighting method with estimated propensity scores was used to minimize data collection bias. Use of intravenous azithromycin was proportional to the severity of respiratory failure (mild: 1.0%, moderate: 3.1%, severe: 14.8%). In the severe group, the 30-day mortality rate was significantly lower with azithromycin (26.49% vs. 36.65%, p = 0.038). In the moderate group, the mean duration of invasive mechanical ventilation after day 8 was shorter with azithromycin; there were no significant differences in other endpoints between the severe and moderate groups. These results suggest that intravenous azithromycin has favorable effects in patients with influenza virus pneumonia using mechanical ventilation or oxygen.

Mechanical and oral antibiotics bowel preparation for elective rectal cancer surgery: A propensity score matching analysis using a nationwide inpatient database in Japan.

Aim: The best bowel preparation method for rectal surgery remains controversial. In this study we compared the efficacy and safety of mechanical bowel preparation (MBP) alone and MOABP (MBP combined with oral antibiotic bowel preparation [OABP]) for rectal cancer surgery. Methods: In this retrospective study we analyzed data from the Japanese Diagnosis Procedure Combination (DPC) database on 37 291 patients who had undergone low anterior resection for rectal cancer from 2014 to 2017. Propensity score matching analysis was used to compare postoperative outcomes between MBP alone and MOABP. Results: A total of 37 291 patients were divided into four groups: MBP alone: 77.7%, no bowel preparation (NBP): 16.9%, MOABP: 4.7%, and OABP alone: 0.7%. In propensity score matching analysis with 1756 pairs, anastomotic leakage (4.84% vs 7.86%, P < 0.001), small bowel obstruction (1.54% vs 3.08%, P = 0.002) and reoperation (3.76% vs 5.98%, P = 0.002) were less in the MOABP group than in the MBP group. The mean duration of postoperative antibiotics medication was shorter in the MOABP group (5.2 d vs 7.5 d, P < 0.001) than in the MBP group. There was no significant difference between the two groups in the incidence of Clostridium difficile (CD) colitis (0.40% vs 0.68%, P = 0.250) and methicillin-resistant Staphylococcus aureus (MRSA) colitis (0.11% vs 0.17%, P = 0.654). There was no significant difference in in-hospital mortality between the two groups (0.00% vs 0.11% respectively, P = 0.157). Conclusion: MOABP for rectal surgery is associated with a decreased incidence of postoperative complications without increasing the incidence of CD colitis and MRSA colitis.

Evaluation of workplace infection prevention and control measures for COVID-19: A prospective cohort study in Japan.

Background: Encouraging the implementation of infection prevention and control (IPC) measures has been necessary to prevent workplace infections caused by the coronavirus disease 2019 (COVID-19). However, the effectiveness of these measures in reducing infections has not been thoroughly evaluated. We evaluated employees' COVID-19 infection rates in relation to the implementation of IPC measures at their workplaces to identify effective workplace measures. Methods: This prospective cohort study was conducted between December 2020 and December 2021 using Internet-based self-assessment questionnaires, with 11,982 participants included from the baseline. To estimate whether implementing workplace IPC measures was associated with COVID-19 incidence rates among participants, we estimated multivariate-adjusted relative risk (RR) using a log-binomial model. Results: After adjusting for sex, age, education, household members, occupation-related factors, and personal preventive behaviors, requesting ill employees to refrain from going to work showed significantly lower COVID-19 infection rates than not requesting it (RR: 0.56, 95% CI: 0.34-0.91, p = 0.019). Conclusions: Employees restricted from reporting to work when ill had significantly lower COVID-19 infection rates than those who did not follow this measure. The results indicated that not coming to work when ill was effective in reducing COVID-19 infections at the workplace. We suggest that companies proactively adopt this policy and encourage their employees to comply with it.

Workplace infection control measures and romantic activities of workers during COVID-19 pandemic: A prospective cohort study in Japan.

Objective: Due to the COVID-19 pandemic, non-married people are at high risk of loneliness. With social interactions restricted, it is important for non-married people to acquire a new romantic partner for their mental health and quality of life. We hypothesized that infection control efforts in the workplace influence people's social interactions, including romantic activities. Methods: We conducted an internet-based prospective cohort study from December 2020 (baseline) to December 2021, using self-administered questionnaires. Briefly, 27,036 workers completed the questionnaires at baseline, and when followed up after 1 year, 18,560 (68.7%) participated. A total of 6,486 non-married individuals with no romantic relationship at baseline were included in the analysis. At baseline they were asked about the implementation of infection control measures in the workplace, and at follow-up they were asked about activities they performed with a view to romantic relationships during the period from baseline to follow-up. Results: Compared to workers in workplaces with no infection control measures, the odds ratio (OR) associated with romance-related activities for those in workplaces with seven or more infection control measures was 1.90 (95% CI: 1.45-2.48, p < 0.001), and the OR associated with having a new romantic partner was 1.79 (95% CI: 1.20-2.66, p = 0.004). Discussion: Under the COVID-19 pandemic, the implementation of infection control measures in the workplace and the expressed satisfaction with those measures promoted romantic relationships among non-married, single individuals.

Factors associated with acceptance of a digital contact tracing application for COVID-19 in the Japanese working-age population.

The working-age population is at the epicenter of coronavirus disease 2019 (COVID-19) infections. Therefore, it is important to increase the acceptance of digital contact tracing apps in this population. Contact-Confirming Application (COCOA) is the only digital contact tracing app in Japan. This study aimed to determine factors associated with acceptance of the COCOA for COVID-19 in the Japanese working-age population. A cross-sectional study was performed for 27,036 full-time workers registered with an internet survey company during December 2020 in Japan. Factors associated with COCOA adoption were evaluated by multivariate logistic regression analysis. The rate of downloading the COCOA was 25.1%. The COCOA was more likely to be accepted by people with married status, university graduation or above, higher income, and occupations involving desk work. Fear of COVID-19 transmission, wearing a mask, using hand disinfection, willingness to be vaccinated against COVID-19, and presence of an acquaintance infected with COVID-19 were also associated with a greater likelihood of adopting the app. The rate of downloading the COCOA in Japan was not very high. The present findings have important implications for widespread adoption of digital contact tracing apps in working-age populations in Japan and elsewhere.

Job stress and work from home during the COVID-19 pandemic among Japanese workers: a prospective cohort study.

Objectives: The work style reforms and the coronavirus disease pandemic in Japan have prompted efforts toward teleworking, mainly work from home (WFH). This study aimed to prospectively evaluate the impact of WFH on job stress among Japanese workers. Methods: This online survey-based prospective cohort study was conducted from December 2020 (baseline) to December 2021 (1-year follow-up) using self-administered questionnaires. At baseline, 27,036 participants completed the questionnaires, whereas 18,560 (68.7%) participated in the 1-year follow-up. After excluding the 11,604 participants who left or changed workplaces within 1 year or who were physical laborers and hospitality workers, data from 6,956 participants were analyzed. We asked participants about WFH frequency at baseline and conducted a follow-up using the Brief Job Stress Questionnaire (BJSQ). Participants were divided into four groups according to WFH frequency. The odds ratios of poor states of the association of the four subscales (job demand, job control, supervisor support, and coworker support) determined by the BJSQ with WFH frequency were estimated using a multilevel logistic model. Results: In both the gender-age adjusted and multivariate models, compared to the non-WFH group, the medium and low WFH groups were less likely to have poor job control, whereas the high WFH group were likely to have similar levels as the non-WFH group. In both models, compared to non-WFH participants, the high WFH group were more likely to have poor supervisor and coworker support. Conclusions: High-frequency WFH requires further attention, because it may increase job stress by exacerbating deficits of social support in the workplace. Medium- and low-frequency WFH workers were more likely to have satisfactory job control; therefore, limiting WFH to three or fewer days per week may lead to better job stress management.