Published papers

Purpose: There is a growing need to understand how cultural, relational, and contextual factors shape the quality of life (QOL) and well-being of caregivers of children with special health and medical needs in East Asia. Currently, no culturally grounded conceptual framework exists, and the unique demands of caring for developmentally dependent children present distinct challenges. This study aimed to identify key factors influencing caregiver QOL and well-being in this context. Methods: We conducted a systematic review of qualitative studies examining QOL among caregivers of children with chronic or life-threatening conditions in East Asia. The databases searched included MEDLINE, Cochrane, EMBASE, PsycINFO, CINAHL, and Ichushi (to June 2024). Studies were included if they addressed informal caregiving for children and focused on QOL or well-being in East Asian countries. Existing reviews were used to identify relevant studies, with an additional search conducted for Japan. We applied a framework synthesis approach guided by the EQ-HWB conceptual model. Risk of bias was assessed using the CASP Qualitative Studies Checklist. Results: Fourteen studies met the inclusion criteria. Ten core themes emerged, including emotions, activity, role, social and family relationships, functioning, financial strain, and parenting. Role, family ties, and parenting were especially prominent in East Asian contexts. Conclusions: Caregivers’ experiences were deeply influenced by cultural factors such as collectivism, traditional norms, and stigma. These findings underscore the importance of culturally sensitive frameworks to assess caregiver QOL and to inform policies and interventions in East Asian health and social systems.

IMPORTANCE The evidence for and against screening for chronic kidney disease in youths who are asymptomatic is inconsistent worldwide. Japan has been conducting urinary screening in students for 50 years, allowing for a full economic evaluation that includes the clinical benefits of early detection and intervention for chronic kidney disease. OBJECTIVES To evaluate the clinical effectiveness and cost-effectiveness of school urinary screening in Japan, with a focus on the benefits of the early detection and intervention for IgA nephropathy, and to explore key points in the model that are associated with the cost-effectiveness of the school urinary screening program. DESIGN, SETTING, AND PARTICIPANTS This economic evaluation with a cost-effectiveness analysis used a computer-simulated Markov model from the health care payer's perspective among a hypothetical cohort of 1 000 000 youths aged 6 years in first grade in Japanese elementary schools, followed up through junior and high school. The time horizon was lifetime. Costs and clinical outcomes were discounted at a rate of 2%per year. Costs were calculated in Japanese yen and 2020 US dollars (¥107 = US $1). INTERVENTIONS School urinary screening for IgA nephropathy was compared with no screening. MAIN OUTCOMES AND MEASURES Outcomes were costs and quality-adjusted life-years (QALYs). Cost-effectiveness was determined by evaluating whether the incremental cost-effectiveness ratio (ICER) per QALY gained remained less than ¥7 500 000 (US $70 093). RESULTS In the base case analysis, the ICERwas ¥4 186 642 (US $39 127)/QALY, whichwas less than the threshold. There were 60.3 patients/1 000 000 patients in the no-screening strategy and 31.7 patients/1 000 000 patients in the screening strategy with an end-stage kidney disease. Costeffectiveness improved as the number of screenings decreased (screening frequency <3 times: incremental cost, -¥75 [US $0.7]; incremental QALY, 0.00025; ICER, dominant), but the number of patients with end-stage kidney disease due to IgA nephropathy increased (40.9 patients/1 000 000 patients). Assuming the disutility due to false positives had a significant impact on the analysis; assuming a disutility of 0.01 or more, the population with no IgA nephropathy had an ICER greater than the threshold (¥8 304 093 [US $77 608]/QALY). CONCLUSIONS AND RELEVANCE This study found that Japanese school urinary screening was cost-effective, suggesting that it may be worthy of resource allocation. Key factors associated with cost-effectiveness were screening cost, the probability of incident detection outside of screening, and IgA nephropathy incidence, which may provide clues to decision-makers in other countries when evaluating the program in their own context.

Background: An early report has shown the clinical benefit of the asymptomatic preoperative severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) screening test, and some clinical guidelines recommended this test. However, the cost-effectiveness of asymptomatic screening was not evaluated. We aimed to investigate the cost-effectiveness of universal preoperative screening of asymptomatic patients for SARS-CoV-2 using polymerase chain reaction (PCR) testing. Methods: We evaluated the cost-effectiveness of asymptomatic screening using a decision tree model from a payer perspective, assuming that the test-positive rate was 0.07% and the screening cost was 8500 Japanese yen (JPY) (approximately 7601 US dollars [USD]). The input parameter was derived from the available evidence reported in the literature. A willingness-to-pay threshold was set at 5 000 000 JPY/quality-adjusted life-year (QALY). Results: The incremental cost of 1 death averted was 74 469 236 JPY (approximately 566 048 USD) and 291 123 368 JPY/QALY (approximately 2 212 856 USD/QALY), which was above the 5 000 000 JPY/QALY willingness-to-pay threshold. The incremental cost-effectiveness ratio fell below 5 000 000 JPY/QALY only when the test-positive rate exceeded 0.739%. However, when the probability of developing a postoperative pulmonary complication among SARS-CoV-2-positive patients was below 0.22, asymptomatic screening was never cost-effective, regardless of how high the test-positive rate became. Conclusions: Asymptomatic preoperative universal SARS-CoV-2 PCR screening is not cost-effective in the base case analysis. The cost-effectiveness mainly depends on the test-positive rate, the frequency of postoperative pulmonary complications, and the screening costs; however, no matter how high the test-positive rate, the cost-effectiveness is poor if the probability of developing postoperative pulmonary complications among patients positive for SARS-CoV-2 is sufficiently reduced.

Background: The proportion of children with chronic diseases reaching adulthood is considered to have increased because their mortality rates have been decreasing. This study aimed to estimate mortality rates due to chronic diseases in children and to analyze recent trends. Methods: We selected diseases from the ICD-10 code that could be a cause of death due to chronic diseases in children. Mortality rates due to the selected chronic diseases among individuals under 20 years of age in Japan were calculated using Vital Statistics from 1995 to 2021. Trends were analyzed overall and by 5-year age groups. Results: Overall mortality rates from chronic diseases among individuals aged 0–19 years gradually declined from 18.8 to 8.1 per 100,000 population aged 0–19 years between 1995 and 2021. Annual percent change was −3.92% (95% CI: −4.45, −3.39) from 1995 to 2004 and −2.60% (95% CI: −2.86, −2.34) from 2004 to 2021. The proportion of chronic disease mortality to all-cause mortality, normalized to the 1995 value, showed no significant change during the study period among individuals aged 0–19 years. The most frequent cause of death was congenital malformations of the circulatory system among those aged 0–4 years and neoplasms among those aged 5–9, 10–14, and 15–19 years. Conclusions: Mortality rates from diseases considered chronic in childhood in our analysis have declined for 27 years. Further investigation of disease prevalence is required to clarify the number of adolescents with chronic diseases who reach adulthood.

Chronic kidney disease (CKD) represents a growing global health challenge, often progressing silently until advanced stages. Persistent proteinuria plays a pivotal role in initiating the fibrotic niche—a complex cellular microenvironment contributing to early kidney fibrosis and closely associated with kidney failure. Despite advancements in CKD management, proteinuria remains underrecognized as a critical surrogate endpoint for disease progression. Urine screening for proteinuria in asymptomatic pediatric populations has been contentious due to concerns about diagnostic reliability, cost-effectiveness, and clinical relevance. However, recent data from Japan present a contrasting perspective. With a well-established nationwide school-based urine screening program, Japan has demonstrated effective early detection and intervention strategies, particularly for conditions such as IgA nephropathy. A 2024 economic evaluation reported an incremental cost-effectiveness ratio well below Japan’s pediatric willingness-to-pay threshold, affirming the program’s economic and clinical viability. These findings underscore the potential of structured screening protocols—especially in regions with underreported disease prevalence or limited healthcare access—to prevent long-term kidney impairment. Modifiable factors such as screening frequency, age of initiation, and integration of emerging biomarkers must be considered to optimize outcomes. This review highlights the need to revisit the role of proteinuria screening in pediatric nephrology, advocating for evidence-informed policy decisions that recognize its long-term value. Japan’s model offers a robust framework for balancing cost, clinical impact, and public health priorities in global efforts to address CKD in its earliest stages.

Background: Few studies have evaluated the efficacy of ultrasonography (US) and abdominal radiography in assessing bladder and bowel dysfunction in children aged <24 months. We aimed to investigate the association between the risk of urinary tract infection (UTI) recurrence and fecal impaction using imaging findings. Methods: The medical records of 121 children (aged <24 months) with initial febrile UTI (fUTI) who were admitted to the authors’ institution from January 2004 to September 2019 were reviewed retrospectively. We evaluated the rectal diameters of children with suspected fecal impaction that were measured using transabdominal US, or the rectal diameters divided by the distance between the ischial spines that were measured using abdominal radiography. Based on previous reports, we defined fecal impaction as a transabdominal US score of >30 mm or an abdominal radiography score of >0.5. The definition of functional constipation was based on the child/adolescent Rome IV criteria – i.e., a maximum stool frequency of twice per week. Results: The median age at initial fUTI diagnosis was 4 months. The occurrence of fecal impaction identified via imaging was significantly greater in patients with UTI recurrence than in those without recurrence: yes/no: 17/9 (65.4%) versus 35/60 (36.8%); P = 0.013. On the other hand, the occurrence rates of constipation based on stool frequency did not differ between the two groups. In multiple logistic analyses, fecal impaction detected via imaging was identified as an independent risk factor for fUTI recurrence. Conclusions: Fecal impaction observed via US and abdominal radiography may be useful in predicting the recurrence of fUTI in children.

Background: A health-economic evaluation related to COVID-19 is urgently needed to allocate healthcare resources efficiently; however, relevant medical cost data in Japan concerning COVID-19 are scarce. Methods: This cross-sectional study investigated the healthcare cost for hospitalized COVID-19 patients in 2021 at Keio University Hospital. We calculated the healthcare costs during hospitalization using hospital claims data and investigated the variables significantly related to the healthcare cost with multivariable analysis. Results: The median healthcare cost per patient for the analyzed 330 patients was Japanese yen (JPY) 1,304,431 (US dollars ~ 11,871) (interquartile range: JPY 968,349–1,954,093), and the median length of stay was 10 days. The median healthcare cost was JPY 798,810 for mild cases; JPY 1,113,680 for moderate I cases; JPY 1,643,909 for moderate II cases; and JPY 6,210,607 for severe cases. Healthcare costs increased by 4.0% for each additional day of hospitalization; 1.26 times for moderate I cases, 1.64 times for moderate II cases, and 1.84 times for severe cases compared to mild cases; and 2.05 times for cases involving ICU stay compared to those not staying in ICU. Conclusions: We clarified the healthcare cost for hospitalized COVID-19 patients by severity in a Japanese university hospital. These costs contribute as inputs for forthcoming health economic evaluations for strategies for preventing and treating COVID-19.

Objective To map existing research on the quality of life (QOL) of parents and other informal caregivers of children with chronic illnesses, describe study characteristics, caregiver and patient populations, and identify the instruments used to measure QOL and their characteristics. Methods Six databases (MEDLINE, EMBASE, Cochrane Library, PsycINFO, CINAHL, Ichushi) were searched up to October 2024. Eligible studies included parents and other informal caregivers of children with chronic illnesses assessed with multidomain QOL questionnaires. Data on study design, populations, conditions, instruments, and outcomes were extracted, and results were synthesized descriptively using counts and percentages. Results Searches identified 3356 records, of which 409 quantitative studies met the inclusion criteria. The number of publications notably increased since 2020. Most studies were observational (73%) and cross-sectional (62%) with small sample sizes. The most frequently studied conditions of children were developmental disorders, asthma, and atopic dermatitis, accounting for over 40% of the studies. Nearly 44% used generic instruments, 60% of studies used caregiver-specific instruments, and only 2.7% employed both. No preference-based measure (PBM) developed for caregivers of children was identified; existing PBMs target caregivers of adult patients. Conclusions This review shows increasing attention to caregiver QOL in pediatric research, reflected by the increasing number of recent publications. However, it reveals that current evidence remains concentrated on common conditions and is reliant on generic or highly disease-specific instruments. To advance inclusive and evidence-based pediatric care and policy, future studies should broaden disease coverage, adopt more rigorous designs, and develop validated PBMs for caregiving contexts.

Background: Medical corporations, which are non-profit organizations that aim to operate hospitals, clinics, or long-term care facilities, account for more than half of all hospital beds and play a central role in the health care system in Japan. However, limited analysis of hospital integration has been performed. Examining the hospital integration trends of medical corporations can provide valuable insights for optimizing health care delivery and resource allocation in Japan. This study conducted a comprehensive analysis of trends in the hospital integration of medical corporations and market concentration in Japan using nationwide longitudinal data. Methods: This longitudinal study evaluated the hospital integration of medical corporations in Japan between 2017 and 2021 using medical corporation financial data provided by the Neostage Company. The target population was medical corporations that own hospitals in Japan. The primary outcomes were the horizontal and vertical integration of medical corporation hospitals. Horizontal integration was defined as the integration of two or more hospitals within the same corporation, while vertical integration was defined as the integration of a hospital with different types of health care facilities, such as clinics or long-term care facilities, within a single medical corporation. The Herfindahl–Hirschman Index (HHI) was calculated to measure hospital market concentration using hospital bed data for medical corporations in all prefectures. Results: The number of hospitals and hospital beds within medical corporations decreased from 5,670 to 848,174 in 2017 to 5,486 and 814,462 in 2021, respectively. Both horizontal and vertical integration among medical corporation facilities showed a gradual upward trend, increasing from 24.92% to 55.75% in 2017 to 26.92% and 59.42% in 2021, respectively. The mean (standard deviation [SD]) HHI increased slightly from 262.7 (178.6) in 2017 to 275.2 (187.9) in 2021, with rural areas being more concentrated than urban areas, although both remained unconcentrated. Conclusions: This longitudinal study revealed a gradual downward trend in the number of hospitals and hospital beds owned by medical corporations, while horizontal and vertical integration gradually progressed without any particular medical corporation dominating the market. These findings are expected to contribute to policymaking efforts aimed at providing optimal health care services in Japan.