Tsubokura Masaharu

• MD, PhD
• Medical Doctor at Fukushima Medical University

Background Maintaining a high participation rate is crucial for effective colorectal cancer (CRC) screening. The COVID‐19 pandemic placed a significant burden on healthcare facilities, which hindered CRC screening efforts. However, the effects of the prolonged pandemic on CRC screening remain unclear. Methods We analyzed data from the Japan COVID‐...

The Fukushima Health Management Survey, conducted by Fukushima Prefecture since the 2011 Great East Japan Earthquake (GEJE), has not identified any health effects from radiation exposure. Complete blood counts (CBC), which are sensitive to radiation exposure, have not shown lymphocytopenia, neutropenia, anemia, or thrombocytopenia, but the white bl...

The Fukushima Daiichi Nuclear Power Plant, managed by the Tokyo Electric Power Company experienced a catastrophic accident in 2011 that led to widespread public anxiety regarding radiation exposure and the long-term impacts of evacuation. The recovery process has considerably varied across the affected municipalities, highlighting the need for effe...

A key issue in the post-COVID-19 era is the ongoing administration of COVID-19 vaccines. Repeated vaccination is essential for preparing against currently circulating and newly emerging SARS-CoV-2 variants while enabling people to continue with daily life. Optimizing vaccination strategies is crucial to efficiently manage medical resources and esta...

Background/Objectives: Limited research has compared tests assessing humoral and cellular immunity related to SARS-CoV-2 infection. This study evaluated immunoglobulin G for nucleocapsid (IgG(N)) and T-spot for nucleocapsid (T-spot(N)) assays against polymerase chain reaction (PCR) test results for identifying infected individuals. Methods: This st...

Prolonged evacuation after disasters increases the risks of diseases and challenges in healthcare access. This study aimed to analyze changes in life expectancy (LE) and years of life lost (YLL) in Fukushima Prefecture after the Great East Japan Earthquake. LE and YLL were calculated based on a dataset of 276,314 deaths in Fukushima Prefecture from...

Disaster-related deaths can be classified as direct and indirect disaster-related deaths that are becoming more predominant in Japan. To reduce indirect disaster-related deaths, accurate statistics based on medical documentation are essential. However, the definition and reporting of such deaths in Japan present systemic challenges. These deaths ar...

Lesbian, gay, bisexual, transgender, and queer (LGBTQ) individuals face significant health disparities worldwide, particularly in preventive medicine. In Japan, where breast cancer has the highest incidence rate among women, understanding screening behaviors among LGBTQ individuals is crucial for improving public health outcomes. This study aimed t...

Background Financial conflicts of interest (FCOIs) between pharmaceutical companies and clinical practice guideline (CPG) authors can influence guideline recommendations, posing challenges to patient care. Despite global concerns, limited research exists on FCOI awareness among healthcare professionals in lower‐middle‐income countries like Nepal....

The Fukushima Daiichi nuclear power plant (FDNPP) accident in 2011 primarily caused indirect adverse effects. Even the indirect adverse effects of radiation/nuclear disasters sometimes lead to death. Japan compensates for disaster-related deaths under the legally enshrined disaster condolence grant system. Studies on disaster-related deaths in area...

Following the 2011 Fukushima Daiichi Nuclear Power Plant accident, public behaviors have been marked by excessive avoidance and stigma, driven by fear and uncertainty regarding radiation exposure and its health implications. Despite extensive media dissemination of information on radiation, the precise nature of the public’s knowledge, beliefs and...

In radiological disasters, evacuating institutionalized individuals such as hospitalized patients and nursing home residents presents complex challenges. The Fukushima Daiichi Nuclear power plant (FDNPP) accident, triggered by the Great East Japan Earthquake (GEJE), exposed critical issues in evacuation planning. This case series investigates the e...

An accurate understanding of the population is essential for the development of medical care and social resources. However, the development of transportation networks has increased temporal and spatial fluctuations in the population, making it difficult to accurately forecast medical care demand, especially during disaster recovery. This study exam...

Thirteen years have passed since the Great East Japan Earthquake and the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident. The lessons learned from the FDNPP accident were that a lack of knowledge about radiation, insufficient information, and inadequate crisis communication led to increased radiation anxiety, reputational damage and disaster...

After the Great East Japan Earthquake, planning appropriate healthcare resource allocation was crucial. However, accurately estimating medical care demand was challenging due to substantial population fluctuations caused by extensive evacuations, compounded by the inaccuracy of conventional Resident Resister data in this context. This study employs...

Radiation disasters can lead to a myriad of direct and indirect health effects. The term ‘disaster-related deaths’ is commonly used in Japan; however, comprehensive studies in regions severely impacted by nuclear accidents are scarce. Our research primarily focuses on Minamisoma City, situated north of the Fukushima Daiichi Nuclear Power Plant (FDN...

This study summarises the responses to information on thyroid cancer, which possibly provoked misunderstanding and unfounded rumour, described in a letter issued by five former Japanese Prime Ministers on 27 January, 2022. Fukushima Medical University (FMU) implemented countermeasures and follow-up in three phases in response to the letter. In Phas...

People generally wish to return home after being evacuated due to disaster situations. Evacuation orders have now been lifted in the Fukushima region following the nuclear accident in 2011, and the Japanese government is promoting a return policy. However, many residents who wish to return home remain unable to and continue living in evacuation sit...

This study investigated the implementation and efficacy of trauma-focused psychotherapies at a psychiatric clinic in Minamisoma City, Fukushima, after the 2011 Great East Japan Earthquake and nuclear disaster. Analyzing medical records from April 2016 to March 2021, the authors identified a significant dropout rate of 43.2% among post-traumatic str...

Objectives While studies have examined the effects of large-scale disasters on disaster-vulnerable individuals, these analyses may not capture the full impact. This study qualitatively explored the impacts of the March 2011 Fukushima triple disaster on patients with breast cancer and their families, aiming to highlight the importance of incorporati...

Background: Disasters and family cancer experiences both significantly impact well-being, especially in disaster-prone areas like Japan. Disruptions in medical care and increased emotional strain make coping with cancer even more challenging. This study explores how these factors together affect well-being in Japan, highlighting the need for furthe...

Objectives To investigate the details of disaster-related deaths due to the indirect health effects of the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident following the Great East-Japan Earthquake in 2011 and serve as a source of reference in the event of similar circumstances in the future. Design A retrospective observational study. Sett...

Introduction Relocation after a disaster often has negative health effects on vulnerable people, particularly older adults. However, little is known about the number of repeated evacuations and relocations after disasters among those experienced disaster-related deaths. This case series aimed to summarize the secondary problems and mortality risks...

Background Lesbian, gay, bisexual, transgender, and queer (LGBTQ) individuals face significant health disparities worldwide, particularly in preventive medicine. In Japan, where breast cancer has the highest incidence rate among women, understanding screening behaviors among LGBTQ individuals is crucial for improving public health outcomes. Objecti...

Objective This study aimed to examine the extent of mental distress among women undergoing breast cancer screening in areas affected by the 2011 Great East Japan Earthquake and Fukushima Daiichi nuclear disaster and to clarify the relationships between radiation risk perception, breast cancer anxiety, and mental distress among this population. Meth...

Background Understanding the waning of immunity after booster vaccinations is important to identify which immune-low populations should be prioritized. Methods We investigated longitudinal cellular and humoral immunity after the third vaccine dose in both high- and low-cellular and humoral immunity groups at the peak immunity phase after the boost...

Background The Great East Japan Earthquake and the subsequent Fukushima nuclear power plant accident in 2011 posed significant challenges to the educational sector, particularly affecting nursing students in the disaster area. However, to the best of our knowledge, there are no reports on the effects of the natural disaster coupled with the nuclear...

Background: Health information seeking via the internet among patients with cancer in disaster-affected areas is underresearched. Objective: This study aims not only to assess the extent and means of web-based health information seeking among patients with cancer living in the disaster-affected area of the 2011 Fukushima triple disaster but also t...

Patients undergoing hemodialysis are particularly vulnerable to severe outcomes of SARS-CoV-2 infection, with mortality rates higher than that of the general population. Vaccination reduces the risk of adverse outcomes, with booster doses being particularly beneficial. However, limited data are available on the effectiveness of subsequent vaccinati...

Introduction Vaccination has been implemented as a useful measure to combat the COVID-19 pandemic. However, there is a tendency for individuals to avoid vaccination due to the possibility of adverse events, making it important to investigate the relationship between COVID-19 vaccines and their adverse events. This study explored longitudinal advers...

Self-exercise during hemodialysis reportedly prevents functional decline. This study aimed to assess the effects of exercise on physical function during hemodialysis. From September 2014 to March 2018, 35 elderly dialysis patients participated in an exercise program 3 times a week for 24 weeks during hemodialysis under staff supervision. The Short...

Following the Great East Japan Earthquake (GEJE) and the Fukushima Daiichi nuclear power plant accident in 2011, mandatory evacuation orders were issued to residents living near the nuclear power plant in Fukushima prefecture, including some patients receiving home oxygen therapy. Although the vulnerability of patients with home oxygen therapy (one...

Objective Evacuation, owing to a disaster, impacts various aspects of an individual's life, including health status. This study aimed to determine the prevalence of obesity among residents of Katsurao Village, Fukushima Prefecture, after the evacuation order due to the Fukushima nuclear disaster in 2011 was lifted in 2016 and to compare the prevale...

Purpose Helicobacter pylori (HP) infection, a risk factor for gastric cancer, is prevalent in Japan. Consequently, some municipalities across Japan are implementing HP screening and treatment programs for adolescents. However, little is known about parents’ attitudes and awareness regarding HP screening for their children. This study aimed to eluci...

It is crucial to anticipate nuclear emergency scenarios and implement effective measures. Japan’s climate and topography make it vulnerable to natural disasters; thus, it is necessary to address compounding and cascading disaster scenarios involving the simultaneous occurrence of natural and nuclear disasters. On January 1, 2024, an earthquake hit...

Large-scale disasters can severely impact breast cancer care, leading to treatment disruptions and delays. While empirical studies on these effects are limited, patient narratives provide valuable insights. This study explored treatment continuity and medical access among local breast cancer patients affected by the 2011 triple disaster through qua...

After the Great East Japan Earthquake, planning the appropriate allocation of healthcare resources is crucial. However, accurately estimating the medical care demand was challenging due to the substantial population fluctuations caused by extensive evacuations. This study employs mobile spatial statistics using NTT DoCoMo’s mobile phone data to con...

When considering disaster preparedness, one challenge is mitigating the health impacts of evacuations. Nuclear disaster preparedness has evolved based on past experiences from numerous disasters, including the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident. However, there is a lack of comprehensive reporting on the awareness of administrati...

There is limited information on whether the COVID-19 pandemic was associated with decreased breast cancer screening uptake and if COVID-19 vaccination was associated with an increase in screening uptake. Our study explored the uptake of breast cancer screening in Japan after the COVID-19 pandemic and assessed its association with the COVID-19 vacci...

This online survey of unvaccinated people living in Japan aimed to identify the reasons for declining vaccination and to develop effective countermeasures. We conducted a hierarchical class analysis to classify participants, examine factors influencing their classification, and provide the information they needed about coronavirus disease 2019 (COV...

Radiation disasters pose distinctive medical challenges, requiring diverse care approaches. Beyond radiation exposure assessment, addressing health impacts due to lifestyle changes, especially among vulnerable populations, is vital. Evacuation orders issued in radiation-affected areas introduce unique healthcare dynamics, with their duration signif...

As we learned during the COVID-19 pandemic, vaccines are one of the most important tools in infectious disease control. To date, an unprecedentedly large volume of high-quality data on COVID-19 vaccinations have been accumulated. For preparedness in future pandemics beyond COVID-19, these valuable datasets should be analyzed to best shape an effect...

Introduction There has been a growing concern over the past few years about the effects of disasters and crises on breast cancer screening, an argument that has been further enhanced by the novel coronavirus disease 2019 (COVID-19) pandemic. However, little is known about how crises might affect the long-term uptake of breast cancer screening progr...

The Fukushima Medical University (FMU) International Symposium on the Fukushima Health Management Survey (FHMS) convened for the fourth time in March 2022 to share FHMS findings within Fukushima and beyond. Dr. TAKENOSHITA Seiichi, FMU President, underscored Fukushima’s restoration journey, while Governor UCHIBORI Masao committed to partnering with...

This study investigates the neutralizing activity against the XBB1.5 variant and the ancestral strain in a population post-bivalent vaccination using a pseudo virus assay validated with authentic virus assay. While bivalent booster vaccination and past infections enhanced neutralization against the XBB 1.5 strain, individuals with comorbidities sho...

The medical situation during disasters often differs from that at usual times. Disasters can lead to significant mortality that can be difficult to monitor. The types of disaster-related deaths are largely unknown. In this study, we conducted a survey to categorize the disaster-related deaths caused by a radiation disaster. A total of 520 people li...

Background Approximately 80% of non-communicable diseases (NCDs) have been reported in low- and middle-income countries (LMICs). However, studies on the usefulness of educational interventions run by non-healthcare workers in combating NCDs in resource-limited areas in rural parts of LMICs are limited. This study aimed to identify the effectiveness...

Predicting the transition of kidney function in chronic kidney disease is difficult as specific symptoms are lacking and often overlooked, and progress occurs due to complicating factors. In this study, we applied time-series cluster analysis and a light gradient boosting machine to predict the trajectories of kidney function in non-dialysis depend...

Introduction The health of patients with mental disorders, such as alcohol-related diseases, often deteriorates after disasters. However, the causes of death among those with alcohol-related diseases during and after radiation disasters remain unclear. Methods To minimize and prevent alcohol-related deaths in future radiation disasters, we analyze...

Background/aim: Disasters can jeopardize breast cancer care and Japan's triple disaster in 2011 (earthquake, tsunami, and nuclear accident) is no exception. However, detailed information is lacking regarding the care of breast cancer related lymphedema (BCRL) following the disaster. We aimed to explore the process by which local patients become aw...

In nuclear disaster prevention, it is essential not only to make daily efforts to prevent accidents from occurring but also to properly apply lessons learned from actual disasters. Although significant changes have been made to nuclear disaster preparedness in Japan since the Fukushima Daiichi Nuclear Power Plant accident, there is insufficient inf...

Background Large-scale disasters can severely affect breast cancer care, leading to treatment disruption and delay. Although few empirical studies have explored these effects, analyzing patients’ narratives can help bridge this gap. This study aimed to explore treatment continuity and medical access among patients with breast cancer during the 2011...

Introduction Following the Great East Japan Earthquake, the living environment of socially isolated older adults has become a pressing concern. In response, Nagaya, a collective housing program, was established in Soma City, Fukushima, Japan to address social isolation among older adults and support their long-term health. This study aimed to ident...

Background Little information is available on the role of community-based rehabilitation after a nuclear disaster. Here, we report the case of an older couple living in an area repopulated after the Fukushima nuclear disaster of 2011 who received outpatient rehabilitation. Case presentation An 84-year-old woman underwent total hip arthroplasty (THA...

In breast cancer surgery, some medical facilities lack the necessary resources to conduct sentinel lymph node biopsy and its intraoperative frozen section consultation. In the coastal rural area of Fukushima, Japan, which has suffered from physician undersupply following the 2011 triple disaster of earthquake, tsunami and nuclear disaster, we explo...

Although studies have demonstrated that infections with various viruses, bacteria, and parasites can modulate the immune system, no study has investigated changes in antibodies against microbial antigens after the COVID-19 mRNA vaccination. IgG antibodies against microbial antigens in the blood of vaccinees were comprehensively analyzed using micro...

Background: After the Great East Japan Earthquake on March 11, 2011 and the subsequent accident at the Tokyo Electric Power Company-operated Daiichi Nuclear Power Plant, the Fukushima Prefecture government initiated the Fukushima Health Management Survey (FHMS) to assess the long-term health effects of the disaster on Fukushima residents. The bloo...

Purpose There is a limited information on whether COVID-19 pandemic was associated with a decreased breast cancer screening uptake and if COVID-19 vaccination was associated with an increase of screening uptake. Our study explored a two-year span (2020 to 2022) uptake of breast cancer screening in Japan after the COVID-19 pandemic and assessed its...

Background Although 12 years have passed since Great East Japan Earthquake and following Fukushima nuclear accident, approximately 40% of Japanese citizen still believe that the current radiation exposure in Fukushima residents will likely/ very likely to cause genetic effects of radiation. This incorrect understanding could continue unexpected dis...

Objectives: The purpose of this research is to describe the social demographics and chief complaints of users of a free medical consultation application in Ibaraki Prefecture, where a free medical consultation application was released. Methods: The present study included users of a telehealth application in Ibaraki Prefecture between April 9 and Ma...

Key Clinical Message During disasters, multiple factors can cause significant delays in medical visits. Regular patient monitoring, high‐risk individual alerts, and telemedicine enhancements can potentially alleviate these issues and ensure timely interventions. Abstract During the COVID‐19 pandemic, a Japanese woman in her 70s delayed her regular...

After the Fukushima nuclear power plant disaster in 2011, the Japanese government implemented a return policy, lifting most evacuation orders in former evacuation areas. Consequently, the return of residents is currently underway. However, it has become common for a large number of residents to carry out multisite living, a lifestyle involving retu...

The medical situation during disasters often differs from that at usual times. Disasters can lead to significant mortality that can be difficult to monitor. The types of disaster-related deaths are largely unknown. In this study, we conducted a survey to categorize the disaster-related deaths caused by a radiation disaster. A total of 520 people li...

The bivalent mRNA vaccine is recommended to address coronavirus disease variants, with additional doses suggested for high-risk groups. However, the effectiveness, optimal frequency, and number of doses remain uncertain. In this study, we examined the long-term cellular and humoral immune responses following the fifth administration of the mRNA sev...

This cross-sectional observational study examined the cluster groups of risk behaviors and beliefs associated with non-communicable diseases (NCDs) and the demographic factors that influence these cluster groups. The questionnaire survey was conducted in Lohagara Upazila in Narail District, Bangladesh and included basic demographics and items assoc...

Background Coronavirus Disease 2019 (COVID-19), a global pandemic, has resulted in millions of deaths worldwide and severely impacted health service delivery systems. Developing countries, including Nepal, faced the risk of health system failure due to limited infrastructures. During the pandemic, Nepal experienced a decline in medical service util...

The objective of this study was to clarify the impact of adverse reactions on immune dynamics. We investigated the pattern of systemic adverse reactions after the second and third coronavirus disease 2019 (COVID-19) vaccinations and their relationship with immunoglobulin G against severe acute respiratory syndrome coronavirus 2 spike 1 protein tite...

Social networking services (SNS) such as Twitter play an important role in the collective knowledge, consensus of citizens and decision making regarding various countermeasures. In particular, since SNS have great power to communicate information in the context of disasters and pandemics, scientists and administrators are required to understand how...

Disasters could jeopardize breast cancer care, and the 2011 Japan’s triple disaster (earthquake, tsunami, and nuclear accident) has been no exception. However, the information is lacking regarding its details, including that concerning breast cancer-related lymphedema (BCRL). We aimed to explore the process of becoming aware of BCRL among the local...

Background: Although 12 years have passed since Great East Japan Earthquake and following Fukushima nuclear accident, approximately 40% of Japanese citizen still believe that the current radiation exposure in Fukushima residents will likely cause genetic effects of radiation. This misunderstanding could continue unexpected discrimination and prejud...

After disasters, direct deaths and secondary health effects, such as diabetes and psychological distress, can occur. It is critical to compare the magnitudes of these risks to promote effective public health measures. In this study, we used the loss of happy life expectancy (LHpLE) to compare the risks associated with diabetes, psychological distre...

: Booster vaccination reduces the incidence of severe cases and mortality related to COVID-19, with cellular immunity playing an important role. However, little is known about the proportion of the population that has achieved cellular immunity after booster vaccination. Thus, we conducted a Fukushima cohort database and assessed humoral and cellul...

Little is known about how crises might affect the long-term uptake of breast cancer screening programs. This study aimed to clarify the long-term trend of breast cancer screening program uptake in Minamisoma City following the 2011 Triple Disaster in Fukushima, Japan (earthquake, tsunami, and nuclear disaster), and to evaluate the factors associate...

Objectives: This study aimed to identify factors that delayed emergency medical services (EMS) in evacuation order zones after the 2011 Great East Japan Earthquake and Fukushima Daiichi Nuclear Power Plant accident and to investigate how the lifting of the evacuation affected these factors over time. Design: This research was a retrospective obs...

In the published publication, there was an error regarding the affiliation for “Tomoya Suzuki” [...]

In this study, we aimed to use the loss of happy life expectancy (LHpLE), an indicator that enables risk assessment considering wellbeing, to compare the risks of environmental carcinogenic chemicals in Japan. First, we surveyed Japanese people to determine their emotional happiness by age and sex and evaluated whether cancer incidence reduced emot...