Background: Health insurance claims data are used in various research fields; however, an overview on how they are used in healthcare research is scarce in Japan. Therefore, we conducted a scoping review to systematically map the relevant studies using Japanese claims data.

Methods: MEDLINE, EMBASE, and Ichushi-Web were searched up to April 2021 for studies using Japanese healthcare claims data. We abstracted the data on study characteristics and summarized target diseases and research themes by the types of claims database. Moreover, we described the results of studies that aimed to compare health insurance claims data with other data sources narratively.

Results: A total of 1,493 studies were included. Overall, the most common disease classifications were "Diseases of the circulatory system" (18.8%, n = 281), "Endocrine, nutritional, and metabolic diseases" (11.5%, n = 171; mostly diabetes), and "Neoplasms" (10.9%, n = 162), and the most common research themes were "medical treatment status" (30.0%, n = 448), "intervention effect" (29.9%, n = 447), and "clinical epidemiology, course of diseases" (27.9%, n = 417). Frequent diseases and themes varied by type of claims databases. A total of 19 studies aimed to assess the validity of the claims-based definition, and 21 aimed to compare the results of claims data with other data sources. Most studies that assessed the validity of claims data compared to medical records were hospital-based, with a small number of institutions.

Conclusions: Claims data are used in various research areas and will increasingly provide important evidence for healthcare policy in Japan. It is important to use previous claims database studies and share information on methodology among researchers, including validation studies, while informing policymakers about the applicability of claims data for healthcare planning and management.

The Tohoku Medical Megabank Brain Magnetic Resonance Imaging Study (TMM Brain MRI Study) was established to collect multimodal information through neuroimaging and neuropsychological assessments to evaluate the cognitive function and mental health of residents who experienced the Great East Japan Earthquake (GEJE) and associated tsunami. The study also aimed to promote advances in personalized healthcare and medicine related to mental health and cognitive function among the general population. We recruited participants for the first (baseline) survey starting in July 2014, enrolling individuals who were participating in either the TMM Community-Based Cohort Study (TMM CommCohort Study) or the TMM Birth and Three-Generation Cohort Study (TMM BirThree Cohort Study). We collected multiple magnetic resonance imaging (MRI) sequences, including 3D T1-weighted sequences, magnetic resonance angiography (MRA), diffusion tensor imaging (DTI), pseudo-continuous arterial spin labeling (pCASL), and three-dimensional fluid-attenuated inversion recovery (FLAIR) sequences. To assess neuropsychological status, we used both questionnaire- and interview-based rating scales. The former assessments included the Tri-axial Coping Scale, Impact of Event Scale in Japanese, Profile of Mood States, and 15-item Depression, Anxiety, and Stress Scale, whereas the latter assessments included the Mini-Mental State Examination, Japanese version. A total of 12,164 individuals were recruited for the first (baseline) survey, including those unable to complete all assessments. In parallel, we returned the MRI results to the participants and subsequently shared the MRI data through the TMM Biobank. At present, the second (first follow-up) survey of the study started in October 2019 is underway. In this study, we established a large and comprehensive database that included robust neuroimaging data as well as psychological and cognitive assessment data. In combination with genomic and omics data already contained in the TMM Biobank database, these data could provide new insights into the relationships of pathological processes with neuropsychological disorders, including age-related cognitive impairment.

Takayasu arteritis (TAK) is a type of large-vessel vasculitis that predominantly affects young females. The precise pathomechanism of TAK is still under investigation. In TAK, the vasa vasorum is considered to be the initial inflammatory site. Disruption of the vasa vasorum induces the entry of inflammatory cells into the vascular wall of large vessels between the media and adventitia, and infiltrated cells damage the vascular components, eventually leading to stenosis or dilatation of the affected arteries. In addition, T cells are considered key players in TAK, and myeloid cells function as effector cells. Although the roles of B cells in TAK are poorly understood, recent evidence supports their contribution to the pathogenicity of TAK. Particularly, two autoantibodies have been identified in TAK through investigation of anti-endothelial cell antibodies, and they could be involved in the maintenance of vascular inflammation. Furthermore, one of the autoantibodies, anti-endothelial protein C receptor, was shown to be present in ulcerative colitis (UC), which is genetically and clinically associated with TAK. Similar autoantibodies in inflammatory diseases with different target organs indicate a common underlying pathophysiology of these diseases, which could be characterized by the aberrant activation of B cells. This review discusses recent understanding of the pathomechanisms of TAK and UC, with a focus on the involvement of B cells and autoantibodies. The close association of UC with TAK further suggests a common etiology, and the importance of the intestinal microbiota, including dysbiosis, is also becoming known in TAK. Investigation of such common factors among TAK and UC would improve understanding of the interplay between gut and vascular inflammation, which is a new concept for developing vascular inflammation through the gut-vessel connection.

Background: Somatostatin analogs are expected to reduce lymphatic leakage. However, whether they can be used after axillary lymphadenectomy is unclear. This study aimed to assess the efficacy and safety of somatostatin analogs in axillary lymphadenectomy for breast cancer patients.

Methods: We performed a random-effects meta-analysis by searching electronic databases for randomized trials and trial registries until June 2022. The primary outcomes were the volume of drained fluid, the duration of drainage, and seroma incidence. Bias was assessed using the Cochrane Collaboration's tool and the Grading of Recommendations, Assessment, Development, and Evaluations approach.

Results: Six trials (738 participants) and one protocol without results were included. Somatostatin analogs may reduce the volume of drained fluid (mean difference = −22.07 mL, 95% confidence interval [CI] = −42.09 to −2.05; I² = 56%) while resulting in a slight-to-no difference in the duration of drainage (mean difference = −0.48 days, 95% CI = −1.43 to 0.46; I² = 87%) and seroma incidence (risk ratio = 0.91, 95% CI = 0.61-1.34; I² = 55%). The certainty of the evidence was low.

Conclusions: There was limited evidence supporting somatostatin analogs for lymphorrhea after axillary lymphadenectomy. Multicenter randomized controlled trials are needed to confirm the efficacy and safety of somatostatin analogs after axillary lymphadenectomy.

Introduction: It is essential to establish appropriate medical quality metrics and make improvements to safely and efficiently deliver optimum emergency medical services. The Ministry of Health, Labor and Welfare (MHLW) recommends prefectures to establish numerical quality metrics in their regional healthcare plans (RHCP). The 7th RHCP was issued by the MHLW in 2017 along with a notice of planning in covering the six-year period from 2018 to 2023. In this descriptive study, the emergency medicine policies in the 7th RHCP of each prefecture were analyzed from a quality improvement perspective.

Method: The authors examined the chapters on emergency medicine in the RHCPs of 47 prefectural governments for the overall structure, cost-benefits, and connection to community-based integrated care systems. The type and number of clinical measures listed as numerical metrics and their classification methods were emphasized.

Result: Regarding the overall plan structure, 40 prefectural governments began their description with an analysis of current surroundings. In total, 24 prefectural governments mentioned community-based integrated care systems but none mentioned cost-benefit analysis. Altogether, only 43 of 47 prefectural governments (91%) indicated numerical metrics. The maximum number of numerical targets for quality measures by prefecture was 19, the minimum was 0, and the median was 4 (IQR: 3-6.5); there were 220 metrics in total, with 82 structural, 96 process, and 42 outcome measures. Additionally, 13 prefectures (28%) classified quality measures according to the MHLW's guidance, 6 (13%) used their own classification manner, while the others did not classify their measures.

Conclusions: There were significant differences in emergency medicine policies and quality metrics among the prefectural governments. Further research is needed to develop and establish more comprehensive and appropriate metrics based on a common methodology to improve the quality of emergency medicine.

Introduction: The coronavirus disease 2019 (COVID-19) pandemic has significantly affected healthcare workers' mental health worldwide, leading to the intention to resign. Japanese medical residents were no exception to the impact of COVID-19. This study aimed to illustrate how the COVID-19 pandemic affected medical residents' intention to resign.

Methods: A cross-sectional study was conducted for Postgraduate Year (PGY) 1-5 medical residents in Japan using an internet survey from March 11 to March 18, 2021. During this survey, the Japanese government declared a second-time state of emergency on January 7, 2021, and all restrictions were expanded nationwide until March 21, 2021. Medical residents were categorized into two groups (intention to resign group [IR] or no intention to resign group [NIR]) based on their intention to resign. Multivariate logistic regression analysis was conducted to elucidate the risk factors for the intention to resign.

Results: 354 medical residents were enrolled in this study (response rate: 40.2%). Ninety-two medical residents (26.0 %) were categorized into IR and 262 (74.0%) into NIR. According to multivariate logistic regression analysis, those who did not have mental support at their hospital had 2.95 times greater chance of intending to resign (Adjusted odds ratio [AOR] = 2.95, 95% confidence interval (CI) [1.42-6.15]). Medical residents who engaged in patients with COVID-19 (AOR = 2.13, 95% Cl [1.08-4.18]) and PGY5 (AOR = 3.38, 95% Cl [1.51-7.56]) had a higher likelihood of intending to resign among residents in all PGY.

Conclusions: One in four medical residents intended to resign during the COVID-19 pandemic. Particularly, PGY5 and medical residents who treated patients with COVID-19 were found at risk of having the intention to resign. At times of crisis, such as the COVID-19 epidemic, establishing a mental health support system that targets high-risk residents is critical.

Introduction: In 2018, the fee schedule for nutrition support teams (NSTs) in Japanese hospitals was changed. The change was intended to encourage more hospitals to establish NSTs, and this study aims to investigate whether this change had the desired effect. Specifically, we will look at the proportion of hospitals with NSTs before and after the 2018 revision to see if there was a significant increase in the number of hospitals with NSTs.

Methods: The study analyzed administrative data from 10 Japanese prefectures dating from June 2015 to September 2021 using an interrupted time-series design. The analysis focused on all acute care hospitals within these prefectures and measured the percentage of hospitals with NSTs. Subgroup analyses were conducted based on hospital size and functions. In April 2018, the intervention, a fee schedule revision, was implemented.

Results: We analyzed 1,471 acute care hospitals. Immediately after the intervention, the percentage of hospitals with NSTs increased by 4.59% (95% CI = 3.92%, 5.26%) and by 0.66% (95% CI = 0.57%, 0.75%) quarterly thereafter. We observed a marked increase in NST formation among large-sized (20.9%), medium-sized (28.0%), and highly acute care hospitals (hospitals with emergency medical care centers and intensive care units, 22.3% and 23.6%, respectively). We also noted a moderate increase among hospitals with convalescent rehabilitation units (10.1%) and a modest increase among small-sized hospitals (6.9%).

Conclusions: Relaxation of the NST fee requirement increased the proportion of hospitals with NSTs in Japan, especially among larger and highly acute care hospitals.

Introduction: Hemodialysis patients have various complications, and orthopedic diseases include carpal tunnel syndrome, spinal canal stenosis, spondylosis destruction, fractures, and osteoarthritis. As a treatment for knee osteoarthritis, intra-articular injections of hyaluronic acid and steroids are performed. In general, steroid injections have a strong short-term anti-inflammatory effect, but there is a risk of complications, such as infection. In addition to aging, dialysis patients are prone to weakened immune systems and susceptibility to infection. Therefore, more attention should be paid to the treatment of osteoarthritis in dialysis patients. This study aimed to compare the effects of steroid and complication of infection of dialysis and non-dialysis patients who underwent intra-articular steroid injection.

Methods: A total of 20 dialysis patients (23 knees) and 20 non-dialysis patients (24 knees) with knee osteoarthritis who underwent steroid injections were investigated. All patients underwent radiographic diagnosis and were evaluated for the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, visual analog scale (VAS), range of motion (ROM), and side effects before, and at 3, and 6 months after injection.

Results: The mean body mass index (BMI) was 21.3 (±standard deviation (SD) 2.8) and 24.9 (±SD 2.6) in dialysis and non-dialysis patients, respectively, showing a significant difference. Both dialysis and non-dialysis patients showed statistically significant improvement in VAS and WOMAC scores after steroid injection. There were no significant differences between dialysis and non-dialysis patients in the gender differences and mean age. There were no infection complications in both groups.

Conclusions: This study revealed the analgesic effect of steroids on knee osteoarthritis in dialysis and non-dialysis patients. On the other hand, there were no infection complications in either patient. These findings suggest that intra-articular steroid injection is safe for dialysis patients.

Introduction: Obesity and inappropriate lifestyle is the major risk factors for liver dysfunction and proteinuria. Nevertheless, previous studies have not described the differential impacts of body weight changes and lifestyle modification on already developed liver dysfunction and proteinuria.

Methods: The original cohort was 933,490 individuals from the Japanese general population. In this investigation, we included 36,256 obese individuals with elevated levels of aspartate aminotransferase and/or alanine aminotransferase (≥31 IU/L) or positive proteinuria (+/− or more) in both the first and second years. Outcomes were the first normalization of these data defined as improvement in liver dysfunction and proteinuria. Times to outcomes were assessed using the Cox proportional hazards modeling for −1 kg/m²/year change in body mass index (BMI) changes in exercise and alcohol intake.

Results: The multivariable-adjusted hazard ratio (HR) for incident improvement in liver dysfunction with BMI change −1.0 kg/m²/year was 1.07 (95% confidence interval [CI] 1.05-1.09) in obesity and that with improved proteinuria was 1.04 (95%CI 1.02-1.07). Compared to subjects without exercise habits, subjects who gained exercise habits exhibited a higher rate of improvement in liver dysfunction (HR 1.08; 95%CI 1.01-1.15) but not in proteinuria (HR 0.98; 95%CI 0.88-1.08). Compared to subjects with continuous alcohol intake habits, subjects who quit alcohol intake also showed a higher rate of improvement in liver dysfunction (HR 1.20; 95%CI 1.09-1.32).

Conclusions: This study suggested that weight loss greater than 1 kg/m²/year improves liver dysfunction and dipstick proteinuria in obesity. Particularly, liver dysfunction can be remedied by acquiring an exercise habit and quitting alcohol intake.

Introduction: Health check-ups have been disrupted worldwide by the COVID-19 pandemic, especially at its beginning. In Japan, undergoing annual check-ups is mandatory for full-time employees of all ages, while those other than full-time employees are entitled to undergo nonmandatory cancer screenings and specific health check-ups. To evaluate the impact of the COVID-19 pandemic on health check-ups, we conducted a nationwide questionnaire survey targeting healthcare facilities.

Methods: A questionnaire survey was conducted between December 10, 2021, and January 28, 2022. Healthcare facilities were eligible if they were members of Japan Society of Ningen Dock and could respond via email. The monthly and yearly numbers of examinees undergoing mandatory or nonmandatory check-ups in 2020 and 2021 were compared with those in 2019. The proportions of examinees requiring follow-up visits and adhering to follow-up visits were compared between 2020 and 2019. Precautions taken against COVID-19 were also investigated.

Results: Of the 1,299 eligible facilities, 639 participated (response rate, 49.2%). Health check-up services were suspended in 484 (75.7%) facilities for a median duration of 5 (interquartile range [IQR]: 4-8) weeks. A total of 19,861,230 and 21,748,125 examinees underwent health check-ups in 591 facilities in 2020 and 2021, respectively, 10.0% and 1.4% less than the numbers in 2019. The number of examinees undergoing health check-ups decreased by a median of 8.3% (IQR: −14.6 to −3.1) in 2020 compared to that in 2019, with the largest decrease of 70.3% (IQR −87.9 to −48.5) in May. Although the number of examinees undergoing mandatory check-ups increased in 2021 compared with that in 2019, the number of those undergoing nonmandatory check-ups remained low.

Conclusions: While people eligible for mandatory check-ups were adherent to check-ups in 2021, those ineligible for mandatory check-ups seemed less adherent. Public health efforts to encourage these people to adhere to check-ups during the pandemic are required.

The 7.8 magnitude earthquake that occurred in southern Turkey on February 6, 2023, has resulted in over 40,000 and 5,000 confirmed deaths in Turkey and Syria, respectively, including substantial infrastructure damage. While Turkey has received assistance from various countries and international organizations, the level of support Syria has received remains unclear. The Assad regime has demanded that aid be sent to the capital Damascus, but this may hinder the delivery of assistance to the areas most severely affected by the earthquake because the affected regions were mainly controlled by rebel forces.

One of the biggest challenges in providing aid is accessing the affected region, as the earthquake occurred close to the border between Syria and Turkey, where roads and other infrastructure are poorly constructed. Furthermore, the northwest area of Syria shelters many internally displaced people, and more than 50% of medical facilities are not functioning due to the ongoing conflict, making the situation more hazardous.

In light of the experience of the Great East Japan Earthquake, securing direct support routes and dispatching medical personnel to the affected areas is crucial for a gradual recovery from the disaster. Therefore, it is essential for the international community, including Japan, to negotiate with the Assad regime to expand direct support routes and provide support for the dispatch of medical personnel who will remain and work in the affected areas. Humanitarian assistance and political issues should be kept separate to avoid further hindrances to aid delivery.

Orthostatic dysregulation (OD), a common psychosomatic disorder in children, is caused by circulation disturbance resulting from autonomic imbalance. OD is a significant public health threat due to its association with school refusal and depression in children. During the COVID-19 pandemic, many children suffered from school closures, lack of exercise, smartphone addiction, and school refusal. The COVID-19 pandemic made it much more difficult to deliver existing approaches to patients and families with OD and increased the risk of prolonged and severe OD. In response, web-based digital health solutions are expected to support patients and families. Digital therapeutics for OD can not only deliver established treatments online, such as pharmacotherapy and behavioral therapy but also provide new interventions, such as regular mental health programs led by clinical psychologists. It is necessary to keep in mind that digital therapeutics are not intended to replace established treatments, but rather to supplement them and provide additional support. However, most research on OD has been conducted in Japan. Therefore, to provide unique findings from Japan, it is important to conduct further epidemiological research using large-scale databases in the real world and reveal the clinical characteristics and detailed epidemiology of OD, leading to the development of novel treatments.

Some specialties require publishing a paper as a prerequisite for becoming a Japanese Medical Specialty Board Specialist. Taking obstetrics and gynecology as an example, we wish to describe some concerns about this. Time limitations oblige residents to publish papers in non-PubMed journals with smaller circulations. Once data have been published, later attempts at secondary publication are difficult. This may bury some important data. Requiring an English presentation and writing an English abstract as a prerequisite for a board specialty may be an option to avoid this. Although we believe that the experience of publishing a paper during residency is important, how to deal with this issue needs further consideration.

Idiopathic normal pressure hydrocephalus (iNPH) with gait disturbance can be effectively treated with a cerebrospinal fluid shunt. Furthermore, balloon kyphoplasty (BKP) is a successful minimally invasive treatment for osteoporotic vertebral compression fractures (VCFs). This case report presents the surgical management of an elderly patient with iNPH who presented after a VCF due to a fall. A 77-year-old woman who had been experiencing progressive gait disturbance for five years reported experiencing back pain one month after a fall. Imaging revealed a recent L1 VCF that did not compromise the spinal canal. Furthermore, the Mini-Mental State Examination results and the timed up-and-go test were 20 points and 17.96 seconds, respectively. Magnetic resonance imaging revealed ventriculomegaly with an Evans' index of 0.35. Her symptoms improved temporarily after a tap test, and she was diagnosed with probable iNPH. BKP was performed for VCFs, followed by the lumboperitoneal (LP) shunt placement for iNPH one month later. Following the operation, her symptoms improved without complications. After one month of performing BKP, an LP shunt would be placed to prevent shunt complications, such as infection and catheter-related neurological symptoms. Screening for iNPH in the elderly who present after VCFs due to a fall may identify iNPH patients who may benefit more from surgical treatments.