Rev1 overexpression accelerates N-methyl-N-nitrosourea (MNU)-induced thymic lymphoma by increasing mutagenesis

Rev1 has two important functions in the translesion synthesis pathway, including dCMP transferase activity, and acts as a scaffolding protein for other polymerases involved in translesion synthesis. However, the role of Rev1 in mutagenesis and tumorigenesis in vivo remains unclear. We previously generated Rev1-overexpressing (Rev1-Tg) mice and reported that they exhibited a significantly increased incidence of intestinal adenoma and thymic lymphoma (TL) after N-methyl-N-nitrosourea (MNU) treatment. In this study, we investigated mutagenesis of MNU-induced TL tumorigenesis in wild-type (WT) and Rev1-Tg mice using diverse approaches, including whole-exome sequencing (WES). In Rev1-Tg TLs, the mutation frequency was higher than that in WT TL in most cases. However, no difference in the number of nonsynonymous mutations in the Catalogue of Somatic Mutations in Cancer (COSMIC) genes was observed, and mutations involved in Notch1 and MAPK signaling were similarly detected in both TLs. Mutational signature analysis of WT and Rev1-Tg TLs revealed cosine similarity with COSMIC mutational SBS5 (aging-related) and SBS11 (alkylation-related). Interestingly, the total number of mutations, but not the genotypes of WT and Rev1-Tg, was positively correlated with the relative contribution of SBS5 in individual TLs, suggesting that genetic instability could be accelerated in Rev1-Tg TLs. Finally, we demonstrated that preleukemic cells could be detected earlier in Rev1-Tg mice than in WT mice, following MNU treatment. In conclusion, Rev1 overexpression accelerates mutagenesis and increases the incidence of MNU-induced TL by shortening the latency period, which may be associated with more frequent DNA damage-induced genetic instability.

Effects of Overweight on Risk of Thyroid Nodules in Children and Adolescents: The Fukushima Health Management Survey

CONTEXT

Examining how overweight/obesity impacts thyroid nodule development in children and adolescents by sex and age can speculate on the mechanism.

OBJECTIVE

We examined whether overweight in children and adolescents are associated with thyroid nodule development by sex and age.

DESIGN

Approximately 300,000 participants who underwent thyroid ultrasonography in the Fukushima Health Management Survey after a nuclear accident were enrolled. Those without nodules in the initial two examinations (1-3 and 4-5 years postaccident) were prospectively assessed for nodule development in the third examination (6-7 years postaccident) relative to baseline overweight status, with an average follow-up of 4.2 years.

SETTING

A population-based prospective cohort study.

PARTICIPANTS

The first and second thyroid examinations involved 299,939 and 237,691 participants, respectively, excluding those with thyroid nodules. After the third examination, 184,519 participants were finalized for analysis.

MAIN OUTCOME MEASURES

Multivariable-adjusted odds ratios of new detected thyroid nodules for overweight participants compared with normal-weight participants.

RESULTS

New thyroid nodules were detected in 660 participants. Being overweight was positively associated with thyroid nodules. The adjusted odds ratio (95% confidence interval) of thyroid nodules for overweight participants compared with other participants was 1.27 (1.04-1.57). Additionally, the multivariable-adjusted odds ratios for males and females with overweight were 1.21 and 1.32, respectively, and those for different age groups (0-9, 10-14, and 15-19 years) ranged from 1.17 to 1.75.

CONCLUSIONS

Being overweight was associated with thyroid nodules in children and adolescents, mostly adolescent females, regardless of their proximity to the nuclear power plant.

Relationship between the Residual Cesium Body Contents and Individual Behaviors among Evacuees from Municipalities near the Fukushima Daiichi Nuclear Power Plant

ABSTRACT

To support estimations of early individual internal doses to residents who suffered from the 2011 accident at the Fukushima Daiichi Nuclear Power Plant (FDNPP), we have sought to use whole-body counter (WBC) measurement results of subjects who lived in municipalities neighboring the FDNPP at the time of the accident. These WBC measurements started several months after the accident; the targeted radionuclides were 134Cs and 137Cs. Our previous study had analyzed the relationship between the residual Cs contents of individuals and evacuation behaviors in the period immediately after the accident for residents of Namie-town, one of the most radiologically affected municipalities. Those results suggested that the first major release event at the FDNPP on 12 March 2011 caused significant exposure, particularly to those who delayed evacuation on that day. The present study expanded its scope to include subjects from four towns neighboring the FDNPP (Namie, Futaba, Okuma, and Tomioka) to gather additional evidence of the exposure that took place on 12 March 2011. Additionally, we investigated the relationship between individual cesium doses and subjects' destinations following the largest release event on 15 March 2011. The study population was 1,145 adults. We first divided the subjects into two evacuation groups depending on the distance from the FDNPP and their evacuation whereabouts (25-km boundary) as of 15:00 on 12 March 2011: the G1 group (≥25 km) and the G2 group (<25 km). We further divided these two subject groups into seven subgroups based on the subjects' destinations as of 0:00 on 16 March 2011. Our four main findings are as follows. (1) The 137Cs detection rate was significantly different between the G1 and G2 groups of Namie-town and Futaba-town but not for those of Okuma-town and Tomioka-town. This result corresponds to the plume passage (flowing toward the northwest to the north) in the afternoon of 12 March 2011 and supports our previous study. (2) The upper-percentile committed effective doses (CEDs) of the G2 groups were higher than those of the G1 groups for all four towns, although the between-group difference varied with the town. The highest CEDs were found in the G2 group of Futaba-town, and the lowest CEDs were in the Namie-town G1 group: 0.16 mSv and 0.04 mSv at the 90th percentile, respectively. The CEDs for both the G1 and G2 groups were relatively high for Okuma-town and Tomioka-town compared to those of the G1 group of Namie-town, although the former subjects were expected to be less exposed on 12 March 2011 and then evacuated to remote places, as did the residents of the other towns. (3) The CEDs of the G1 subgroup that evacuated outside Fukushima Prefecture were extremely low, suggesting that these subjects were little exposed on both 12 and 15 March 2011. However, the CEDs of the same G1 subgroup were rather higher than those of the corresponding G2 subgroup for Futaba-town and Okuma-town. We thus speculate that the WBC measurements were likely to have been affected by the contamination occurring in the second-round temporary re-entry (except for the Namie-town residents). (4) The analyses of the Namie-town evacuees indicated that the area including the middle and northern parts of Fukushima Prefecture was relatively more affected by the major release event on 15 March 2011. In conclusion, the early cesium intake due to the FDNPP accident remained detectable in the WBC measurements of certain present subjects; however, further analyses of the available data are necessary for a full understanding of the WBC measurement results.

Prevalence of thyroid diffuse goiter and its association with body mass index and the presence of cysts and nodules in children and adolescents: the Fukushima Health Management Survey

The main cause of diffuse thyroid goiter is autoimmune chronic thyroiditis, otherwise known as Hashimoto's thyroiditis. Thyroid hormones play pivotal roles in growth and development during childhood. However, the prevalence of diffuse goiter and the relationships between diffuse goiter, thyroid volume, cysts and nodules, and anthropometric measurements in children are not well known. Among 789,459 participants who participated in thyroid ultrasound examinations, 320,206 participants (male: 161,728; female: 158,478) aged 1-23 years were analyzed. Logistic regression analyses were conducted to calculate the odds ratios of the standard deviation score of body mass index (BMI-SDS), the SDS of bilateral width multiplied thickness area (BWTAR-SDS) as a provisional determination of thyroid volume, and the presence of nodules or cysts for positive diffuse goiter compared with negative diffuse goiter after correction for sex and age. The prevalence of diffuse goiter increased in a female-dominant manner with aging. Compared with the absence of diffuse goiter, the age- and sex-adjusted odds ratios (95% confidence intervals) for BMI-SDS (1 SD), BWTAR-SDS (1 SD), cysts, and nodules were 1.24 (1.21-1.27), 3.21 (3.13-3.29), 0.53 (0.50-0.58), and 1.38 (1.17-1.64), respectively. The odds ratios of nodules for positive diffuse goiter were 4.18 (1.08-16.08), 1.76 (1.01-3.07), 1.80 (1.32-2.45), and 1.34 (1.08-1.67) in the age groups 1-7, 8-11, 12-15, and 16-23 years, respectively. The age-dependent increase in the prevalence of diffuse goiter was independently associated with increased BMI and positive prevalence of nodules in young individuals.

Nuclear DNA damage-triggered ATM-dependent AMPK activation regulates the mitochondrial radiation response

PURPOSE

AMP-activated protein kinase (AMPK) acts as a cellular energy sensor and is essential for controlling mitochondrial homeostasis. Here, we investigated the regulatory mechanisms involved in AMPK activation to elucidate how networks of intracellular signaling pathways respond to stress conditions.

MATERIALS AND METHODS

Inhibitors of ATM, DNA-PK, and AKT were tested in normal TIG-3 and MRC-5 human fibroblasts to determine which upstream kinases are responsible for AMPK activation. SV40 transformed-human ATM-deficient fibroblasts (AT5BIVA) and their ATM-complemented cells (i.e., AT5BIVA/ATMwt) were also used. Protein expression associated with AMPK signaling was examined by immunostaining and/or Western blotting.

RESULTS

Radiation-induced nuclear DNA damage activates ATM-dependent AMPK signaling pathways that regulate mitochondrial quality control. In contrast, hypoxia and glucose starvation caused ATP depletion and activated AMPK via a pathway independent of ATM. DNA-PK and AKT are not involved in AMPK-mediated mitochondrial signaling pathways.

CONCLUSION

Activation of the AMPK signaling pathway differs depending on the stimulus. Radiation activates AMPK through two pathways: depletion of ATP-mediated LKB1 signaling and nuclear DNA damage-induced ATM signaling. Nuclear DNA damage signaling to mitochondria therefore plays a pivotal role in determining the cell fates of irradiated cells.

Relationship between evacuation after the Great East Japan Earthquake and new-onset hyperuricemia: A 7-year prospective longitudinal study of the Fukushima Health Management Survey

INTRODUCTION

On March 11, 2011, the Great East Japan Earthquake occurred in Japan, with a nuclear accident subsequently occurring at the Fukushima Daiichi Nuclear Power Plant. The disaster forced many evacuees to change particular aspects of their lifestyles. However, the effect of evacuation on the new-onset of hyperuricemia have not been sufficiently elucidated. This study assessed the association between evacuation and new-onset hyperuricemia after the earthquake based on the Fukushima Health Management Survey from a lifestyle and socio-psychological perspective.

MATERIALS AND METHODS

This is a 7-year prospective longitudinal study included 18,140 residents (6,961 men and 11,179 women) with non-hyperuricemia who underwent both the Comprehensive Health Check and the Mental Health and Lifestyle Survey in fiscal year 2011. Associations between new-onset hyperuricemia and lifestyle- and disaster-related factors, including evacuation, were estimated using a Cox proportional hazards regression model analysis. Hyperuricemia was defined as uric acid levels > 7.0 mg/dL for men and > 6.0 mg/dL for women.

RESULTS

During a median follow-up of 4.3 years, 2,996 participants (1,608 men, 23.1%, 1,388 women, 12.4%) newly developed hyperuricemia. Significant associations were observed between evacuation and onset of hyperuricemia in women (adjusted hazard ratio 1.18, 95% confidence interval, 1.05-1.32, p = 0.007), but not in men (adjusted hazard ratio 1.11, 95% confidence interval, 0.99-1.24, p = 0.067).

DISCUSSION

Evacuation after a natural disaster is an independent risk factor for the new-onset of hyperuricemia in women. The possibility of hyperuricemia developing in response to natural disasters should be considered.

Newly discovered genomic mutation patterns in radiation-induced small intestinal tumors of ApcMin/+ mice

Among the small intestinal tumors that occur in irradiated mice of the established mouse model B6/B6-Chr18MSM-F1 ApcMin/+, loss of heterozygosity analysis can be utilized to estimate whether a deletion in the wild-type allele containing the Adenomatous polyposis coli (Apc) region (hereafter referred to as Deletion), a duplication in the mutant allele with a nonsense mutation at codon 850 of Apc (Duplication), or no aberration (Unidentified) has occurred. Previous research has revealed that the number of Unidentified tumors tends to increase with the radiation dose. In the present study, we investigated the molecular mechanisms underlying the development of an Unidentified tumor type in response to radiation exposure. The mRNA expression levels of Apc were significantly lower in Unidentified tumors than in normal tissues. We focused on epigenetic suppression as the mechanism underlying this decreased expression; however, hypermethylation of the Apc promoter region was not observed. To investigate whether deletions occur that cannot be captured by loss of heterozygosity analysis, we analyzed chromosome 18 using a customized array comparative genomic hybridization approach designed to detect copy-number changes in chromosome 18. However, the copy number of the Apc region was not altered in Unidentified tumors. Finally, gene mutation analysis of the Apc region using next-generation sequencing suggested the existence of a small deletion (approximately 3.5 kbp) in an Unidentified tumor from a mouse in the irradiated group. Furthermore, nonsense and frameshift mutations in Apc were found in approximately 30% of the Unidentified tumors analyzed. These results suggest that radiation-induced Unidentified tumors arise mainly due to decreased Apc expression of an unknown regulatory mechanism that does not depend on promoter hypermethylation, and that some tumors may result from nonsense mutations which are as-yet undefined point mutations.

Confounding factors and biases involved in regional differences in the detection rate of thyroid cancer in the second-round Thyroid Ultrasound Examination: the Fukushima Health Management Survey

In response to concerns about health due to radiation exposure, the Fukushima Prefecture launched the Thyroid Ultrasound Examination program for residents aged 0-18 years at the time of the earthquake. Herein, we considered the confounding factors involved in the regional differences in the development of thyroid cancer. In this study, the 242 065 individuals who participated in both first- and second-round surveys were classified into four groups by address according to their air radiation dose. The number of participants diagnosed as malignant or suspicious for malignancy by cytological examination were 17, 38, 10 and 4 with detection rates of 53.8, 27.8, 21.7 and 14.5 per 100 000 participants in Regions 1, 2, 3 and 4, respectively. Sex (P = 0.0400), age at the time of the primary examination (P < 0.0001) and interval between the first- and second-round surveys (P < 0.0001) were significantly different among the four regions, and these were suspected to be confounding factors affecting regional differences in malignant nodule detection rates. In addition, significant regional differences were observed in the participation rate in the confirmatory examination (P = 0.0037) and the fine needle aspiration cytology implementation rate (P = 0.0037), which could be potential biases. No significant regional differences in the detection of malignant nodules were found in the multivariate logistic regression analysis after adjusting for the survey interval alone or for sex, age and survey interval. The confounding factors and biases identified in this study that may have important impacts on thyroid cancer detection rate should be fully considered in future studies.

Eight-Year Trends in the Effect of the Great East Japan Earthquake on Obstetrics Outcomes: A Study from the Fukushima Health Management Survey

Information regarding the longitudinal effects of natural/environmental disasters on obstetrics outcomes is limited. This study aimed to analyze the longitudinal changes in obstetrics outcomes over 8 years after the Great East Japan Earthquake and the Fukushima power plant accident. We used data from the first 8 years of the Pregnancy and Birth Survey by the Fukushima prefectural government, launched in 2011. We compared data on obstetrics outcomes by year and divided Fukushima Prefecture into six districts based on administrative districts. Longitudinal changes in the occurrence of preterm birth before 37 gestational weeks, low birth weight, and anomalies in newborns were accessed using the Mantel-Haenszel test for trends in all six districts. Overall, 57,537 participants were included. In 8 years, maternal age, conception rate after sterility treatment, and cesarean section delivery incidence increased. Although significant differences were observed in preterm birth and low birth weight occurrence among districts, there was no significant trend in the occurrence of preterm birth, low birth weight, and anomalies in newborns in all six districts of Fukushima Prefecture. The Great East Japan Earthquake and Fukushima power plant accident were associated with increased cesarean section delivery incidence but had no significant adverse effects on obstetrics outcomes.

Impact of Lifestyle and Psychosocial Factors on the Incidence of Hepatobiliary Enzyme Abnormalities After the Great East Japan Earthquake: Seven-Year Follow-up of the Fukushima Health Management Survey

OBJECTIVE

Residents who lived near the Fukushima Power Plant accident were forced to change their lifestyle after the 2011 accident. This study aimed to elucidate the association of resident lifestyle and psychological factors with onset of hepatobiliary enzyme abnormalities (HEA) after the accident.

METHODS

This longitudinal study included 15705 residents who underwent a comprehensive health check, as well as a mental health and lifestyle survey between June 2011 and March 2012. Follow-up surveys were conducted between June, 2012 and March 2018. Risk factors for new HEA onset were evaluated using the Cox proportional hazards model, moreover, population attributable risks for new HEA onset were calculated.

RESULTS

HEA developed in 29.7% of subjects. In addition to metabolic factors such as overweight, hyperglycemia, and hyperlipidemia; there were differences in alcohol intake, evacuation, unemployment, educational background, and psychological distress between subjects with and without HEA onset. After we adjusted for potential confounding factors, an association of being overweight, hypertension, and dyslipidemia, as well as alcohol consumption, evacuation, and psychological distress with increased risk of HEA onset was realized. Among these identified risk factors, evacuation accounted for the greatest share.

CONCLUSIONS

Metabolic characteristics and disaster-related lifestyle aspects, including mental status, were risk factors for HAE onset after the Fukushima Power Plant accident.

Comparison between external and internal doses to the thyroid after the Fukushima Daiichi Nuclear Power Plant accident

To analyze the association between radiation dose and thyroid cancer after the 2011 Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, external doses have often been used because of the difficulty to estimate internal thyroid doses individually due to the lack of human data. However, no evaluation has been made as to whether external dose is a good surrogate marker for internal thyroid dose individually. This study aimed at analyzing the relationship between external doses and internal thyroid doses estimated by recently developed methodology. For four municipalities affected by the accident, 200 individuals aged under 20 at the time of the accident per municipality were randomly selected, and their external and internal thyroid doses and their ratios were estimated individually. In a separate analysis, median and arithmetic mean values for external thyroid doses estimated for persons of 16 municipalities that included the above four were compared with those for previously estimated internal thyroid doses. The ratios of the median of internal thyroid dose to that of external thyroid dose in these 16 municipalities ranged from 0.56 to 13.8 for 15-year-old children and 0.91 to 21.1 for 1-year-old children. No consistent relationship between external and internal thyroid doses was found in all 16 municipalities. Thus, thyroid doses from both external and internal exposures should be used to analyze the association between radiation dose and thyroid cancer detection rates for persons who lived in Fukushima Prefecture at the time of the FDNPP accident. (240).

Posttraumatic stress response following the loss of significant close others in the Great East Japan Earthquake: Fukushima Health Management Survey

During the Great East Japan Earthquake, many people experienced the loss of family and friends, among other traumatic events. This study sought to clarify the impact of the loss of significant close others on posttraumatic stress symptoms (PTSS), as well as the factors associated with PTSS, among individuals who experienced the loss of significant close others (i.e., bereaved group). Self-administered questionnaires were mailed to men and women (N = 180,604) aged 16 years and older living in municipalities that included evacuated areas surrounding the Tokyo Electric Power Company's Fukushima Daiichi Nuclear Power Station, which was significantly damaged following an earthquake and tsunami in March 2011, causing subsequent radiation leakage; this mailing yielded a 40.7% response rate, with 57,388 valid responses, in 2012. We used the Posttraumatic Stress Disorder Checklist-Specific (PCL-S) to measure PTSS as the outcome variable. Loss of significant close others in the disaster and respondents' relationship with the deceased constituted the explanatory variables. Basic characteristics and disaster-related factors were the confounding variables. Data were analyzed using chi-square tests and logistic regression analyses. The bereaved group showed more severe PTSS than the nonbereaved group, aOR = 1.58, 95% CI [1.50, 1.67]. The risk of developing PTSS increased if the deceased was a respondent's spouse, aOR = 1.67, 95% CI [1.22, 2.29]; child, 1.51 [1.01, 2.25]; or friend, 1.33 [1.16, 1.53]. Individuals who lose significant close others, including both family and friends, in disasters require close mental health care and, if necessary, should be referred for psychiatric treatment.

Longitudinal Trends in Blood Pressure Associated with The Changes in Living Environment Caused by the Great East Japan Earthquake: The Fukushima Health Management Survey

The Great East Japan Earthquake occurred on 11 March 2011, forcing Fukushima Prefecture residents to change their living environment. Such sudden changes possibly have long-term effects on cardiovascular-related diseases. We therefore sought to identify temporal relationships between living environment changes and blood pressure levels over three years following the earthquake. Participants included 14,941 men and 21,533 women aged 16 years or older who answered self-administered questionnaires, including questions on living environment changes at baseline (2012). Blood pressure levels were measured each year from 2012 to 2015. Linear mixed-effects models were used to analyze associations between living environment changes and blood pressure levels. Men with changes in living environment (i.e., those living in shelters or in temporary housing, rental apartments, relatives' houses, or others) showed significantly higher diastolic blood pressure levels than those who lived in their home at baseline (77.3 mmHg vs. 77.8 mmHg; p < 0.001). The time-dependent effect of diastolic blood pressure levels associated with living environment was not statistically significant, indicating a sustained difference in diastolic blood pressure associated with living environment changes at baseline after three years. The effect of living environment changes on diastolic blood pressure increment was also evident in men without antihypertensive medication use during the study period and in men who were current drinkers at baseline. There were no associations between living environment changes and diastolic blood pressure levels among women. Sudden changes in living environment due to the disaster had an impact on the long-term effects of higher diastolic blood pressure among middle-aged men.

Influence of post-disaster evacuation on childhood obesity and liver dysfunction: The Fukushima Health Management Survey

BACKGROUND

After the Great East Japan Earthquake and subsequent Fukushima Daiichi Nuclear Power Plant accident in 2011, the Fukushima Prefectural Government launched a long-term health management survey for the population of Fukushima. Results of the Comprehensive Health Check (CHC) showed that some children aged 6-15 years, who resided in the evacuation area at the time of the disaster, had obesity, hyperlipidemia, liver dysfunction, and/or renal dysfunction from as early as 2011. The aim of the present study was to determine the long-term trend of obesity and hepatic enzyme abnormalities in Fukushima children.

METHODS

We evaluated the changes in body mass index standard deviation score (BMI-SDS), aspartate aminotransferase, alanine aminotransferase, and gamma-glutamyl transpeptidase from 2011 to 2018.

RESULTS

Obesity (BMI-SDS ≥ 2) was significantly associated with hepatobiliary enzyme abnormalities. The mean BMI-SDS was significantly higher in 2011 after the disaster, but then soon showed a gradual decrease. The frequency of obesity did not increase significantly after the disaster. There were no significant differences in the prevalence of hepatobiliary enzyme abnormalities in the children aged 6-15 years of either sex from 2011 to 2018.

CONCLUSIONS

In the present study, we found that the increase in the mean BMI-SDS after the disaster was temporary, suggesting that the frequency of obesity and liver dysfunction might not have been significantly influenced by the disaster.

Ultrasonography-based reference values for the cross-sectional area of the thyroid gland in children and adolescents: The Fukushima Health Management Survey

We previously described the thyroid volume, which was calculated by measuring the thyroid width, thickness, and longitudinal length using ultrasonography, in children and adolescents. We have proposed a simplified method for quantitatively assessing the thyroid size, to overcome the inaccuracy and challenges in measuring the longitudinal length of the thyroid. Based on measurements of 317,847 (girls: 156,913, boys: 160,934) children and adolescents, we calculated sex-specific means and standard deviations of thyroid width and thickness, and of the cross-sectional area computed by multiplying them, for every age and 0.1 m² of body surface area, after ensuring normal distribution with Box-Cox transformation. Multivariate regression analysis revealed that female sex, age, and body surface area were independently associated with areas of each thyroid lobe. Our novel method may be useful in quantitatively assessing the thyroid size, and appropriately diagnosing pathological conditions, such as hypoplasia, atrophy, and enlargement of the thyroid gland, in children and adolescents.

Blood data trends of children in Fukushima after the Great East Japan Earthquake: Fukushima health management survey

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 blood tests of children aged ≤15 years between 2011 and 2012 did not reveal any changes regarding peripheral blood data; however, long-term monitoring is still necessary. Therefore, this study aimed to investigate the long-term health status of children aged ≤15 years who had evacuated the Fukushima Prefecture.

METHODS

From 2011 to 2018, 71,250 evacuees aged 15 years or younger participated in the FMHS and were subjected to blood tests. By analyzing the data of the comprehensive health check survey managed by the FHMS, we examined the changes in hemoglobin (Hb) levels, white blood cell (WBC) counts, including fractions, and platelet (PLT) counts among children from 2011 to 2018.

RESULTS

Minor fluctuations in Hb levels, PLT counts, and WBC counts were observed during the study period, but the central 95% intervals of distribution of the laboratory values were generally within previously reported reference intervals. In particular, there was no increase in the proportions of patients with anemia, polycythemia, or deviating WBC counts.

CONCLUSION

From 2011 to 2018, there was no increase in the percentages of children with anemia, polycythemia, or deviating WBC counts among the Fukushima Prefecture evacuees.

Obesity and glucose metabolism abnormalities by post-disaster evacuation

BACKGROUND

The objectives of this study were to determine the longer-term trends in childhood obesity and glucose metabolism abnormalities among residents of Fukushima Prefecture 5 years after the Great East Japan Earthquake.

METHODS

We evaluated the changes in height, weight, body mass index (BMI), BMI SD score, fasting plasma glucose (FPG) concentration, and hemoglobin A1c (HbA1c) among elementary and junior high school residents who had lived in the evacuation zone between 2011 and 2015.

RESULTS

Of the residents, 11,112 received health checks in 2011, while in 2012, 2013, 2014, and 2015, 5,737, 4522, 4297 and 3405 received health checks, respectively. The mean BMI SD score for all participants in 2011 was 0.149, and this score gradually decreased from 2011 to 2015. FPG levels and HbA1c levels for all participants with a BMI value +2SD or more in 2011 were higher than those in residents with a BMI value of less than +2SD. The frequency of participants with a FPG level of 126 mg/dl or more and the frequency of participants with a HbA1c level of 6.5% or more in 2011 were higher than those in 2012, 2013, and 2015.

CONCLUSIONS

These results suggest that a number of pediatric residents suffered from obesity and glucose metabolism abnormalities. However, the longer-term observations indicated an improvement in obesity and glucose metabolism abnormalities. There was a strong association observed between obesity and glucose metabolism, thus, it is important to continue with health checks for children with obesity and strive to improve their health.

Association between Dairy Product intake and Risk of Osteoporotic Fractures in Postmenopausal Japanese Women: Secondary Analysis of 15-Year Follow-Up data from the Japanese Population-Based Osteoporosis (JPOS) Cohort Study

OBJECTIVES

Few prospective cohort studies have evaluated the relationship between dairy product intake frequency and risk of osteoporotic fractures in Asians. This study aimed to investigate the association between habitual dairy product intake and risk of osteoporotic fractures.

DESIGN

Secondary analysis of prospective cohort study.

SETTING

Five municipalities of Japan.

PARTICIPANTS

This study included 1,429 postmenopausal Japanese women (age ≥45 years at baseline).

MEASUREMENTS

Baseline milk-intake frequency was obtained using nurse-administered questionnaires. Intakes of yogurt and cheese, and estimated calcium intake, were assessed using a validated food frequency questionnaire. Osteoporotic fracture was defined as a clinical fracture diagnosed using radiography. Hazard ratios (HRs) with 95% confidence intervals (CIs) were estimated using Cox proportional hazards models.

RESULTS

Over a median follow-up period of 15.1 years (interquartile range [IQR], 10.1-15.4 years; total, 18,118 person-years), 172 women sustained at least one osteoporotic fracture. The proportions of participants with milk intakes <1, 1, and ≥2 cups/d were 34.4%, 48.0%, and 17.6%, respectively. After adjustment for age, frequency of yogurt intake, frequency of cheese intake, body mass index, history of osteoporotic fractures, and frequency of natto intake, the HRs compared with that for milk intake <1 cup/d were 0.71 (95% CI: 0.51-0.98) and 0.57 (95% CI: 0.35-0.92) for 1 cup/d and ≥2 cups/d, respectively. After adjustment for bone mineral density, HR significance for milk intakes ≥2 cups/d remained significant. Yogurt and cheese intakes were not related to the risk of osteoporotic fractures.

CONCLUSION

High habitual milk intake, but not a habitual yogurt or cheese intake is associated with a decreased risk of osteoporotic fractures, independent of bone mineral density, in postmenopausal Japanese women.

A Six-Year Prospective Study on Problem Drinking among Evacuees of the Great East Japan Earthquake: The Fukushima Health Management Survey

Evacuees of the Great East Japan Earthquake have experienced adverse, long-term physical and psychological effects, including problem drinking. This study examined the risk and recovery factors for problem drinking among evacuees between fiscal years (FY) 2012 and 2017 using data on residents in the evacuation area from the Mental Health and Lifestyle Survey. With the FY 2012 survey as a baseline, a survey comprising 15,976 men and women was conducted in the evacuation area from FY 2013 to FY 2017, examining the risk and protective factors for problem drinking. Particularly, the Cutting down, Annoyed by criticism, Guilty feeling, and Eye-opener (CAGE) questionnaire was used to evaluate problem drinking. Univariate and multivariate Cox proportional hazard models were constructed to identify the risk and recovery factors of problem drinking. The findings indicated that the male gender, insufficient sleep, job change, trauma symptoms, mental illness, family financial issues, and heavy drinking (≥4 drinks per day) were significant risk factors for the incidence of problem drinking among the evacuees. Furthermore, a high blood pressure diagnosis could exacerbate problem drinking among men, while younger age and a diabetes mellitus diagnosis could increase problem drinking among women. Trauma symptoms and heavy drinking inhibited recovery from problem drinking after the disaster. Understanding these factors can shape effective long-term intervention strategies to physically and psychologically support evacuees.

Melatonin and MitoEbselen-2 Are Radioprotective Agents to Mitochondria

Mitochondria are responsible for controlling cell death during the early stages of radiation exposure, but their perturbations are associated with late effects of radiation-related carcinogenesis. Therefore, it is important to protect mitochondria to mitigate the harmful effects of radiation throughout life. The glutathione peroxidase (GPx) enzyme is essential for the maintenance of mitochondrial-derived reactive oxygen species (ROS) levels. However, radiation inactivates the GPx, resulting in metabolic oxidative stress and prolonged cell injury in irradiated normal human fibroblasts. Here, we used the GPx activator N-acetyl-5-methoxy-tryptamine (melatonin) and a mitochondria-targeted mimic of GPx MitoEbselen-2 to stimulate the GPx. A commercial GPx activity assay kit was used to measure the GPx activity. ROS levels were determined by using some ROS indicators. Protein expression associated with the response of mitochondria to radiation was assessed using immunostaining. Concurrent pre-administration or post-administration of melatonin or MitoEbselen-2 with radiation maintained GPx activity and ROS levels and suppressed mitochondrial radiation responses associated with cellular damage and radiation-related carcinogenesis. In conclusion, melatonin and MitoEbselen-2 prevented radiation-induced mitochondrial injury and metabolic oxidative stress by targeting mitochondria. These drugs have the potential to protect against acute radiation injury and late effects of carcinogenesis in a variety of radiation scenarios assuming pre-administration or post-administration.

Morphology dynamics in intestinal crypt during postnatal development affect age-dependent susceptibility to radiation-induced intestinal tumorigenesis in Apc Min/+ mice: possible mechanisms of radiation tumorigenesis

Age at exposure is a major modifier of radiation-induced carcinogenesis. We used mouse models to elucidate the mechanism underlying age-related susceptibility to radiation-induced tumorigenesis. Radiation exposure in infants was effective at inducing tumors in B6/B6-Chr18 MSM-F1 Apc  Min/+ mice. Loss of heterozygosity (LOH) analysis revealed that interstitial deletion may be considered a radiation signature in this model and tumor number containing a deletion correlated with the susceptibility to radiation-induced tumorigenesis as a function of age. Furthermore, in Lgr5-eGFP-ires-Cre  ERT2; Apc  flox/flox mice, deletions of both floxed Apc alleles in Lgr5-positive stem cells in infants resulted in the formation of more number of tumors than in adults. These results suggest that tumorigenicity of Apc-deficient stem cells varies with age and is higher in infant mice. Three-dimensional (3D) immunostaining analyses indicated that the crypt architecture in the intestine of infants was immature and different from that in adults concerning crypt size and the number of stem cells and Paneth cells per crypt. Interestingly, the frequency of crypt fission correlated with the susceptibility to radiation-induced tumorigenesis as a function of age. During crypt fission, the percentage of crypts with lysozyme-positive mature Paneth cells was lower in infants than that in adults, whereas no difference in the behavior of stem cells or Paneth cells was observed regardless of age. These data suggest that morphological dynamics in intestinal crypts affect age-dependent susceptibility to radiation-induced tumorigenesis; oncogenic mutations in infant stem cells resulting from radiation exposure may acquire an increased proliferative potential for tumor induction compared with that in adults.

Associations Between External Radiation Doses and the Risk of Psychological Distress or Post-traumatic Stress After the Fukushima Daiichi Nuclear Power Plant Accident: the Fukushima Health Management Survey

BACKGROUND

The relationship between radiation levels and mental health status after a nuclear disaster is unknown. We examined the association between individual external radiation doses and psychological distress or post-traumatic stress after the Fukushima Daiichi nuclear power plant accident in March 2011 in Japan.

METHODS

The Mental Health and Lifestyle Survey was conducted from January 2012. Based on the estimated external radiation doses for the first 4 months, a total of 64,184 subjects were classified into <1 mSv, 1 to <2 mSv, and ≥2 mSv groups. Odds ratios (ORs) and 95% confidence intervals (CIs) of psychological distress and post-traumatic stress, with the <1 mSv group as the reference, were calculated using logistic regression analysis adjusted for age, sex, evacuation, perception of radiation risk, and subjective health status.

RESULTS

The prevalence of psychological distress/post-traumatic stress in the <1 mSv, 1 to <2 mSv, and ≥2 mSv groups was 15.1%/22.1%, 14.0%/20.1%, and 15.0%/21.7%, respectively. In women, although the ≥2 mSv group tended to have a higher risk of psychological distress with the age-adjusted OR of 1.13 (95% CI, 0.99-1.30), the adjusted OR decreased to 1.00 (95% CI, 0.86-1.16) after controlling for all variables. On the other hand, there were no dose-dependent associations between radiation dose and post-traumatic stress.

CONCLUSION

Although external radiation doses were not associated with psychological distress, evacuation and perception of radiation risk may increase the risk of psychological distress in women in the higher dose group.

External Doses Available for Epidemiological Studies Related to the Fukushima Health Management Survey: First 4-month Individual Doses and Municipality-average Doses for the First Year

BACKGROUND

One of the components of the Fukushima Health Management Survey (FHMS) is the Basic Survey, which estimates individual external doses for the first 4 months after the 2011 nuclear power plant accident. However, external exposure continues long-term. According to estimations by international organizations, the external dose during the first year accounts for a significant part of the long-term dose. Thus, the present study was intended to estimate the first-year doses by extrapolating the Basic Survey results.

METHODS

For most municipalities of non-evacuated areas, ambient dose rate had been continuously measured for at least one designated point in each municipality after the accident. In the present study, a municipality-average dose received by residents for a period was assumed to be proportional to the ambient dose measured at the designated point of that municipality during the same period. Based on this assumption, 4-month municipality-average doses calculated from the Basic Survey results were extrapolated to obtain first-year doses.

RESULTS

The extrapolated first-year doses for 49 municipalities in the non-evacuated areas had a good correlation with those estimated by UNSCEAR, although the extrapolated doses were generally higher (slope of the regression line: 1.23). The extrapolated municipality-average doses were in reasonable agreement (within 30%) with personal dosimeter measurements, suggesting that the extrapolation was reasonable.

CONCLUSION

The present paper reports the first 4-month average doses for all 59 municipalities of Fukushima Prefecture and the extrapolated first-year doses for 49 municipalities. The extrapolated doses will be the basis for future epidemiological studies related to the FHMS.

Trends in Lifestyle-related Diseases and Their Risk Factors After the Fukushima Daiichi Nuclear Power Plant Accident: Results of the Comprehensive Health Check in the Fukushima Health Management Survey

Residents were forced to evacuate owing to the radiation released after the Fukushima Nuclear Power Plant (NPP) accident following the Great East Japan Earthquake on 11/03/2021; thus, their lifestyles drastically changed. The Comprehensive Health Check (CHC) of the Fukushima Health Management Survey (FHMS) was performed to evaluate health statuses and prevent lifestyle-related diseases in evacuation area residents. The first part of the CHC survey is a retrospective analysis of pre- and post-disaster data on health check-ups of evacuation area residents. The second part is a cross-sectional, prospective analysis of post-disaster (fiscal year (FY) 2011-2017) data on health check-ups. Subjects were men and women living in 13 municipalities in areas surrounding the NPP in Fukushima Prefecture. Post-disaster (FY 2011-2012) overweight, hypertension, dyslipidemia, diabetes mellitus, metabolic syndrome, liver dysfunction, hyperuricemia, polycythemia and atrial fibrillation cases increased from the pre-disaster (FY 2008-2010) levels. This tendency was strongest among residents who were forced to evacuate. Proportion of overweight people remained unchanged, the prevalence of liver dysfunction decreased and the proportion of people with treated hypertension and dyslipidemia increased during FY 2011-2017. Meanwhile, the prevalence of diabetes mellitus and mean levels of HbA1c increased. Furthermore, Evacuees showed higher risks of diabetes mellitus, dyslipidemia, chronic kidney diseases and liver dysfunction than non-evacuees. Therefore, residents in the evacuation area, especially evacuees, are at high risk of developing lifestyle-related diseases, especially cardiovascular diseases; therefore, it is necessary to observe health statuses and implement measures to prevent lifestyle-related diseases.

A Comprehensive Review of the Progress and Evaluation of the Thyroid Ultrasound Examination Program, the Fukushima Health Management Survey

The Great East Japan Earthquake on March 11, 2011, and the subsequent tsunami caused an accident at the Fukushima Daiichi Nuclear Power Plant, in which extensive damage to the nuclear power reactors resulted in massive radioactive contamination. Fukushima Prefecture implemented the Thyroid Ultrasound Examination (TUE) program as part of the Fukushima Health Management Survey project in response to residents' anxieties about health risks due to radiation exposure for residents aged 0-18 years at the time of the nuclear accident. This program consisted of the primary examination and the confirmatory examination. In the primary examination, thyroid nodules and cysts were examined using portable ultrasound apparatuses. The confirmatory examination was performed to have clinical or cytological diagnosis. As of June 30, 2021, 116, 71, 31, 36, and 9 examinees in the first, second, third, and fourth round of surveys, and the survey at age 25 years, respectively, were determined to have nodules cytologically diagnosed as malignant or suspicious for malignancy. The confirmatory examination of the fourth-round survey and the primary and confirmatory examination of fifth-round survey are currently in progress. Together with the low thyroid absorbed radiation dose estimated in the United Nations Scientific Committee on the Effects of Atomic Radiation 2020 report, our results suggested that the increased incidence of childhood thyroid cancer in Fukushima Prefecture was not caused by radiation exposure, but rather by the highly sensitive detection method. As detailed in this review, there were ongoing challenges in our program, such as actions against the risk of overdiagnosis and psychological support for participants and their families.

Long-Term, Community-based Approach for Affected People Having Problems With Mental Health and Lifestyle Issues After the 2011 Fukushima Disaster: the Fukushima Health Management Survey

A Mental Health and Lifestyle Survey (MHLS) has been conducted yearly as part of the Fukushima Health Management Survey since 2012, in order to monitor different health issues related to long-term evacuation of affected people after the 2011 Fukushima disaster. This survey is a mail-based one of nearly 210,000 affected people living in the evacuation zone at the time of the disaster. Another purpose of the MHLS is to provide efficient interventions by telephone based on the results of the survey. Significant findings contributing to understanding of non-radiological health effects caused by long-term evacuation were obtained from the MHLS, directly connecting to telephone-based interventions for over 3,000 respondents per year. In this article, the mental health outcomes of the MHLS, including depressive symptoms and posttraumatic responses, are reviewed, and the usefulness of telephone-based interventions is discussed. The evidence showed that, despite improvement of core mental health outcomes, the prevalence of respondents at high risk of some psychiatric problems remained high compared to that among the general population in Japan. In particular, several mental health consequences of respondents staying outside of Fukushima Prefecture were higher than those staying inside Fukushima. Along with further efforts to increase the response rate, we need to continue and modify the MHLS to meet the requirements of the affected people and communities.

Achievements and Current Status of the Fukushima Health Management Survey

The Fukushima Health Management Survey (FHMS) was established in response to the Fukushima Daiichi Nuclear Power Plant accident on March 11, 2011. The primary objectives of the study are to monitor residents' long-term health and promote their future well-being, and to determine the health effects of long-term low-dose radiation exposure. This special issue summarizes the results and current status of the FHMS and discusses the challenges and future directions of the FHMS. The FHMS, a cohort study of all people who were residents in Fukushima Prefecture at the time of the accident, consists of a Basic Survey, Thyroid Ultrasound Examination, Comprehensive Health Check, Mental Health and Lifestyle Survey, and Pregnancy and Birth Survey. The radiation exposure was estimated based on the behavioral records examined using the Basic Survey. Although the response rate was low in the Basic Survey, the representativeness of the radiation exposure data was confirmed using additional surveys. There appears to be no relationship between the radiation exposure and risk of thyroid cancer, although more thyroid cancer cases were detected than initially expected. The ongoing Comprehensive Health Check and Mental Health and Lifestyle Survey have provided evidence of worsening physical and mental health status. The Pregnancy and Birth Survey showed rates of preterm delivery, low birth weight, and congenital abnormalities similar to the national average. Considering the above evidence, the Fukushima Prefectural Government decided to end the Pregnancy and Birth Survey at the end of March 2021, as recommended by the Prefectural Oversight Committee. The framework of the FHMS has not changed, but the FHMS needs to adapt according to the survey results and the changing needs of the eligible residents and municipalities.

Revisiting the Geographical Distribution of Thyroid Cancer Incidence in Fukushima Prefecture: Analysis of Data From the Second- and Third-round Thyroid Ultrasound Examination

BACKGROUND

After the first-round (Preliminary Baseline Survey) ultrasound-based examination for thyroid cancer in response to the accident at the Fukushima Daiichi Nuclear Power Plant in 2011, two rounds of surveys (Full-scale Survey) have been carried out in Fukushima Prefecture. Using the data from these surveys, the geographical distribution of thyroid cancer incidence over 6 or 7 years after the disaster was examined.

METHODS

Children and adolescents who underwent the ultrasound-based examinations in the second- and/or third-round (Full-scale) survey in addition to the first-round survey were included. With a discrete survival model, we computed age, sex, and body mass index standardized incidence ratios (SIRs) for municipalities. Then, we employed spatial statistics to assess geographic clustering tendency in SIRs and Poisson regression to assess the association of SIRs with the municipal average absorbed dose to the thyroid gland at the 59-municipality level.

RESULTS

Throughout the second- and third-round surveys, 99 thyroid cancer cases were diagnosed in the study population of 252,502 individuals. Both flexibly shaped spatial scan statistics and maximized excess events test did not detect statistically significant spatial clustering (P = 0.17 and 0.54, respectively). Poisson regression showed no significant dose-response relationship: the estimated relative risks of lowest, middle-low, middle-high, and highest areas were 1.16 (95% confidence interval [CI], 0.52-2.59), 0.55 (95% CI, 0.31-0.97), 1.05 (95% CI, 0.79-1.40), and 1.24 (95% CI, 0.89-1.74).

CONCLUSION

There was no statistical support for geographic clustering or regional association with radiation dose measures of the thyroid cancer incidence in the cohort followed up to the third-round survey (fiscal years 2016-2017) in Fukushima Prefecture.

Effects of External Radiation Exposure Resulting From the Fukushima Daiichi Nuclear Power Plant Accident on the Health of Residents in the Evacuation Zones: the Fukushima Health Management Survey

BACKGROUND

Associations have been reported between lifestyle-related diseases and evacuation after the Great East Japan Earthquake (GEJE). However, the relationship between lifestyle-related diseases and the effective radiation dose due to external exposure (EDEE) after the GEJE remains unclear.

METHODS

From among 72,869 residents of Fukushima Prefecture (31,982 men; 40,887 women) who underwent a comprehensive health check in fiscal year (FY) 2011, the data of 54,087 residents (22,599 men; 31,488 women) aged 16 to 84 years were analyzed. The EDEE data of 25,685 residents with incomplete results from the basic survey, performed to estimate the external radiation exposure dose, were supplemented using multiple imputation. The data were classified into three groups based on EDEE (0 to <1, 1 to <2, and ≥2 mSv groups and associations between the incidence of diseases and EDEE from FY2011 to FY2017 were examined using a Cox proportional hazards model, with FY2011 as the baseline.

RESULTS

A higher EDEE was associated with a greater incidence of hypertension, diabetes mellitus, dyslipidemia, hyperuricemia, liver dysfunction, and polycythemia from FY2011 to FY2017 in the age- and sex-adjusted model. However, after further adjustment for evacuation status and lifestyle-related factors, the significant associations disappeared. No association was found between EDEE and other lifestyle-related diseases.

CONCLUSION

EDEE was not directly associated with the incidence of lifestyle-related diseases after the GEJE. However, residents with higher external radiation doses in Fukushima Prefecture might suffer from lifestyle-related diseases related to evacuation and the resultant lifestyle changes.

Effects of External Radiation Exposure on Perinatal Outcomes in Pregnant Women After the Fukushima Daiichi Nuclear Power Plant Accident: the Fukushima Health Management Survey

BACKGROUND

This study aimed to investigate the effects of maternal exposure to external radiation on perinatal outcomes among women who experienced the Fukushima Daiichi Nuclear Disaster (FDND) using the Fukushima Health Management Survey (FHMS).

METHODS

Data from the Pregnancy and Birth Survey and Basic Survey in the FHMS were combined to analyze external maternal radiation exposure following the FDND, and the relationship between radiation dose and perinatal outcomes was analyzed using binomial logistic regression analysis. Missing dose data were supplemented using multiple imputation.

RESULTS

A total of 6,875 individuals responded to the survey. Congenital anomalies occurred in 2.9% of patients, low birth weight (LBW) in 7.6%, small for gestation age (SGA; <10th percentile) in 8.9%, and preterm birth in 4.1%. The median maternal external radiation dose was 0.5 mSv (maximum, 5.2 mSv). Doses were classified as follows: <1 mSv (reference), 1 to <2 mSv, and ≥2 mSv. For congenital anomalies, the crude odds ratio for 1 to <2 mSv was 0.81 (95% confidence interval [CI], 0.56-1.17) (no participants with congenital anomaly were exposed to ≥2 mSv). At 1 to <2 mSv and ≥2 mSv, the respective adjusted odds ratios were 0.91 (95% CI, 0.71-1.18) and 1.21 (95% CI, 0.53-2.79) for LBW, 1.14 (95% CI, 0.92-1.42) and 0.84 (95% CI, 0.30-2.37) for SGA, and 0.91 (95% CI, 0.65-1.29) and 1.05 (95% CI, 0.22-4.87) for preterm birth.

CONCLUSION

External radiation dose due to the FDND was not associated with congenital anomalies, LBW, SGA, or preterm birth.

The Effects of the Great East Japan Earthquake on Perinatal Outcomes: Results of the Pregnancy and Birth Survey in the Fukushima Health Management Survey

There are limited studies on the long-term effects of natural/environmental disasters, especially nuclear disasters, on obstetric outcomes. This study aimed to review the results of perinatal outcomes immediately after the Great East Japan Earthquake (GEJE) and the Fukushima Daiichi Nuclear Power Plant accident, as well as their long-term trends over 8 years, in the Fukushima Health Management Survey. The annual population-based Pregnancy and Birth Survey is conducted as part of the Fukushima Health Management Survey. The Fukushima Prefecture government launched it to assess the health conditions of pregnant women and their neonates after the GEJE. The self-reported questionnaire was sent to 115,976 pregnant women by mail from January 2012, with 58,344 women responding to the questionnaire (50.3% response rate). Pregnancy complications, such as gestational hypertension, respiratory diseases, and mental disorders, increased in some women who were pregnant at the time of the earthquake and immediately after the earthquake. However, the direct effects on newborns, such as preterm birth, low birth weight, and congenital anomalies, were not immediately clear after the earthquake. Although there were significant differences in the occurrence of preterm birth and low birth weight among the districts, there was no change in the occurrences of preterm birth, low birth weight, or anomalies in newborns in Fukushima Prefecture from the fiscal year 2011 to the fiscal year 2018. Therefore, the long-term effects of the post-disaster radiation accident on perinatal outcomes are considered to be very small.

Effects of oxygen on the response of mitochondria to X-irradiation and reactive oxygen species-mediated fibroblast activation

PURPOSE

In living organisms, sensitivity to radiation increases in the presence of oxygen (O₂) compared with that under anoxic or hypoxic conditions. Here, we investigated whether O₂ concentration affected the response of mitochondria to X-rays radiation, which is associated with tumor microenvironment formation via fibroblast activation in radiation-related tumors.

MATERIALS AND METHODS

O₂ concentrations were controlled at <5% (internal environmental oxygen condition) or anoxic levels during culture of normal human diploid lung fibroblasts TIG-3 and MRC-5. Protein expression associated with the response of mitochondria to radiation was assessed using immunostaining or western blotting.

RESULTS

Induction of DNA damage (marker: γ-H2A histone family member X) and mitochondrial signaling (AMP-activated protein kinase), suppression of mitochondrial metabolic activity, and generation of reactive oxygen species occurred with radiation in cells cultured under 5% and 20% O₂ conditions. However, reducing O₂ concentration mitigated the effects of radiation on cell growth, mitochondrial damage (parkin), induction of antioxidant responses (nuclear factor E2-related factor 2), and fibroblast activation (α-smooth muscle actin). Radiation did not affect the markers used in this study in the absence of O₂.

CONCLUSION

O₂ concentration affected the response of mitochondria to radiation and reactive oxygen species-mediated fibroblast activation. Higher O₂ concentrations enhanced the effects of radiation on mitochondria in human fibroblasts. In vitro studies may overestimate in vivo radiation effects due to high O₂ concentrations.

Development of a Japanese Healthy Diet Index: The Fukushima Health Management Survey 2011

A novel healthy diet index for dietary quality can be used to assess food intake. After the Great East Japan Earthquake in 2011, the Fukushima Health Management Survey collected dietary data using a short-form food frequency questionnaire (FFQ). The current study included eligible participants (n = 64,909) aged 16-84 years who answered the FFQ in 2011. The year- and sex-specific dietary patterns were determined via principal component analysis. Based on the typical Japanese, juice/dairy, and meat patterns, healthy diet index (HDI) scores were assigned for food items, resulting in Spearman's correlation coefficients of 0.730, -0.227, and -0.257, respectively. The mean (standard deviation) of the HDI scores (range: 1-18) were 9.89 (2.68) in men and 9.96 (2.58) in women. Older individuals, women, nonsmokers, those in good health and with regular physical exercise, and those who did not transfer residences had a high HDI score. In the confirmatory analysis, the adjusted odds ratio (95% confidence interval) of the highest vs. the lowest quartiles of HDI scores was 0.87 (0.80, 0.94) for overweight, 0.89 (0.81, 0.97) for large waist circumference, and 0.73 (0.66, 0.80) for dyslipidemia. The HDI score obtained using the FFQ can be applied to evaluate dietary profiles.

Association between Dietary Diversity and Sociopsychological Factors and the Onset of Dyslipidemia after the Great East Japan Earthquake: Fukushima Health Management Survey

This study aimed to clarify the relationship between the onset of low-density lipoprotein hypercholesterolemia (hyper-LDLemia), high-density lipoprotein hypocholesterolemia (hypo-HDLemia), and hyper-triglyceridemia (hyper-TGemia) and lifestyle/socio-psychological factors among Fukushima evacuation area residents after the Great East Japan Earthquake. Participants included 11,274 non-hyper-LDLemia, 16,581 non-hypo-HDLemia, and 12,653 non-hyper-TGemia cases in the Fiscal Year (FY) 2011. In FY2011, these participants underwent a health checkup and responded to a mental health and lifestyle survey. The onset of each disease was followed through FY2017. The evacuation experience was positively associated with the risk of hyper-LDLemia, hypo-HDLemia, or hyper-TGemia. Conversely, the middle high dietary diversity score was negatively associated with the onset of hyper-TGemia. Moreover, low sleep satisfaction was positively associated with hypo-HDLemia and hyper-TGemia. The "almost never" exercise habit was positively associated with hypo-HDLemia. Current smoking and audible nuclear power plant explosions were positively associated with the risk of hyper-TGemia. Drinking habits exhibited a negative association with the onset of hyper-LDLemia, hypo-HDLemia, and hyper-TGemia. The results of this study indicate the need for continuous improvement in lifestyle, as well as efforts to eliminate the impact of disasters to prevent the onset of dyslipidemia among disaster evacuees.

Possible Association Between Thyroid Nodule Formation and Developmental Alterations in the Pituitary-Thyroid Hormone Axis in Children and Adolescents: The Fukushima Health Management Survey

Background: We previously found low thyrotropin (TSH) levels in children and adolescents with thyroid nodules, including papillary thyroid cancer, although it is generally accepted that high TSH levels are a risk factor for formation and growth of thyroid nodules in adults. To clarify the reasons for the discrepancy, we precisely analyzed the features of pituitary-thyroid hormone (TH) actions in children and adolescents with or without nodules at different ages. Methods: Among the 4955 participants who participated in a second screening by thyroid ultrasound examination in the Fukushima Health Management Survey, 721 and 2849 euthyroid participants aged 6-20 years without or with nodules, including thyroid cancer, were selected for evaluation of TH regulation. The responsivity of TSH to THs was assessed by two thyroid feedback quantile-based indices (T4FQI and T3FQI). Logistic regression analyses were conducted to calculate the odds ratios (ORs) of serum concentrations related to thyroid functions for positive thyroid nodules compared with negative nodules. Results: The feedback indices declined in a sex-specific manner with aging. In particular, T3FQI, the index for TSH response to free triiodothyronine (fT3), started to decline after ∼10 and 15 years of age in female and male participants, respectively. Compared with the absence of nodules, the age- and sex-adjusted ORs (confidence intervals) for logTSH, free thyroxine (fT4), fT3, T4FQI, T3FQI, and thyroglobulin levels were 0.586 (0.501-0.685), 1.036 (0.595-1.805), 1.059 (0.842-1.332), 0.569 (0.454-0.715), 0.564 (0.443-0.719), and 1.01 (1.005-1.014), respectively. Associations between the presence of nodules and either low logTSH or low feedback indices were observed in participants aged between 12 and 17 years among the total cohort. Conclusions: The relationships between the levels of TSH and THs changed in a sex-dependent manner in children and adolescents. The age-dependent shift in the pituitary-TH set point may be associated with age-dependent nodule formation during restricted periods of growth and maturation in both young female and male participants.

Impact of right ventricular reserve on exercise capacity and quality of life in patients with left ventricular assist device

Background

Right heart failure following left ventricular assist device (LVAD) implantation is a major complication which significantly impairs functional capacity and quality of life (QoL). Right ventricular (RV) reserve function may limit exercise capacity and QoL in LVAD patients; however, most patients show normal RV haemodynamics at rest.

Purpose

The aim of this study was to investigate whether RV reserve assessed by the changes of RV function during exercise is correlated with exercise capacity and QoL in patients with LVAD.

Methods

We prospectively examined 20 consecutive LVAD patients who were admitted to our university hospital between June 2020 and November 2021 after excluding those who were unable to perform exercise (n=8). All patients underwent invasive exercise right heart catheterisation with simultaneous echocardiography in the supine position. RV stroke work index (RVSWI) was calculated as 0.0136 × stroke volume index × (mean pulmonary artery pressure [mPAP] − right atrial pressure [RAP]) at rest and during exercise. Exercise capacity and QoL were assessed by 6-minute walk distance (6MWD) and peak oxygen consumption (VO2) in cardiopulmonary exercise testing, and the EuroQol visual analogue scale (EQ-VAS), respectively. The patients were divided into two groups according to the median ΔRVSWI (RVSWI change from rest to peak exercise) of 1.45 (interquartile range [IQR] −0.31 to 8.25) g/m2.

Results

Patients were predominantly male (75%) and the median age was 47 (IQR 38–60) years. Patients with lower ΔRVSWI had significantly higher change on RAP (P=0.019), but significantly lower change on mPAP (P&lt;0.001) compared to those with higher ΔRVSWI. There were no significant differences in age, gender, primary aetiology of heart failure, type of LVAD devices, or echocardiographic parameters including tricuspid annular plane systolic excursion, and RVSWI at rest between the groups. ΔRVSWI during exercise were positively correlated with 6MWD (R=0.69, P&lt;0.01) and peak VO2 (R=0.66, P&lt;0.01) (Figure A). In addition, ΔRVSWI during exercise were positively correlated with the EQ-VAS (R=0.48, P=0.031). On the other hand, there was no significant correlation between RVSWI at rest and 6MWD (R=−0.11, P=0.63) and peak VO2 (R=0.13, P=0.95), and the EQ-VAS (R=0.11, P=0.61). During a median follow-up period of 312 (IQR 176–369) days, adverse events occurred in 3 patients (15%), including 1 death and 2 hospitalisations for major bleeding and right heart failure. Kaplan-Meier analysis revealed that the adverse events more frequently occurred in patients with lower ΔRVSWI compared to those with higher ΔRVSWI (Figure B).

Conclusions

ΔRVSWI was positively correlated with 6MWD, peak VO2 and EQ-VAS irrespective of RV function at rest. Our findings suggest that the assessment of RV reserve function using ΔRVSWI would be useful for risk stratification in patients with LVAD.

Funding Acknowledgement

Type of funding sources: None.

Trends and outcomes of early rehabilitation in intensive care unit for patients with cardiovascular disease – a cohort study with propensity score-matched analysis

Background

Early rehabilitation in the intensive care unit (ICU), including early mobility therapy, is known to improve the clinical outcomes in patients with critically ill. However, the effectiveness of acute-phase cardiovascular rehabilitation (CR) during ICU treatment have not been thoroughly evaluated in patients with cardiovascular disease (CVD).

Purpose

We aimed to investigate the trends and outcomes of acute-phase CR in the ICU for patients with CVD, including in-hospital and long-term clinical outcomes.

Methods

We reviewed 1948 consecutive patients with CVD admitted to tertiary academic ICU at a university hospital. Patients were arbitrarily assessed by an ICU team consisting of medical and surgical doctors, nurses and physiotherapists within 24 hours after admission to ICU to discover whether their rehabilitation could be initiated according to the specific clinical trial and statement. As clinical characteristics, disease aetiology, comorbid conditions, and ICU treatment were obtained from an electronic database. We evaluated the probability of return to walking independence and return to home as in-hospital clinical outcomes. All patients were followed for five years and investigated all-cause and cardiovascular events after hospital discharge as long-term clinical outcomes. The associations between the implementation of CR during ICU treatment (ICU-CR) and clinical outcomes were evaluated using propensity score-matched analysis with adjustment for clinical characteristics in all matched patients and various subgroups, including aged &gt;65 years, surgical patients, emergency, and length of ICU stay ≥48 hours.

Results

Out of studied patients, 1092 patients received ICU-CR, the number of which positively correlated with year-trend (r=0.986, P&lt;0.001). After propensity score matching with adjustment for clinical characteristics including calendar years, 758 patients were included for analysis (pairs of n=379 ICU-CR and non-ICU-CR). The ICU-CR was significantly associated with a higher probability of return to walking independence (incident rate ratio [IRR], 2.04; 95% confidence interval [CI], 1.77–2.36) and return to home (IRR, 1.22 95% CI, 1.05–1.41). These associations were consistently observed in various subgroups regarding CVD conditions (Figure 1). During the median follow-up periods of 2.6 years, all-cause clinical events and cardiovascular events occurred in 289 patients (38.1%) and 153 patients (20.2%), respectively. The ICU-CR showed significantly lower rates of five-year all-cause and cardiovascular events than non-ICU-CR (hazard ratio [95% CI] for all-cause events and cardiovascular events, 0.71 [0.56–0.89] and 0.69 [0.50–0.95], respectively, Figure 2).

Conclusions

The implementation of acute-phase CR in the ICU increased with year-trend, considered beneficial to improve in-hospital and long-term clinical outcomes in patients with CVD and various subgroups of relatively severe disease conditions.

Funding Acknowledgement

Type of funding sources: None.

Association between the changes in walking speed during 6 months after discharge and subsequent prognosis in older patients with heart failure: report from a multicenter prospective cohort study

Background

Walking speed (WS) is one of the key components of physical frailty associated with a prognosis in patients with heart failure (HF). However, the prognostic impact of changes in WS after discharge in patients with HF remains to be examined.

Purpose

The purpose of this study was to examined the association between the change in WS during 6 months after discharge and subsequent prognosis in older patients with HF.

Methods

This study was performed as a sub-analysis of the multicenter cohort study in Japan (FLAGSHIP). We analyzed patients hospitalized for HF aged ≥65 years whose WS was measured at discharge and after 6 months of discharge. Based on the patterns of WS at the two points, patients were divided into four groups (A: WS ≥0.98 m/s both at discharge and 6-month; B: ≥0.98 m/s at discharge, &lt;0.98 m/s at 6-month; C: &lt;0.98 m/s at discharge, ≥0.98 m/s at 6-month; D: &lt;0.98 m/s both at discharge and 6-month). WS &lt;0.98 m/s has been identified as a cut-off value predicting the prognosis of HF in the main analysis of the FLAGSHIP. Kruskal - Wallis test was used to compare among groups. Furthermore, Cox proportional hazards model was performed to evaluate the association between the WS subgroups and HF rehospitalization after 6-month of discharge. Additionally, adjustments were made for age and sex in model 1, and for age, sex, cognitive function (Mini-mental state examination, MMSE ≤23), past HF hospitalization, rehospitalization within 6 months after discharge, and variables with a p value &lt;0.05 both at discharge and 6 months in univariate analysis in model 2.

Results

A total of 890 patients were included in this study (Group A: n=386, B: n=51, C: n=143, D: n=310). There was a significant difference in HF rehospitalization after 6-month of discharge among the four groups (Log-rank test, p=0.01, Figure 1). In the crude model, hazard ratio (HR) of group B compared with A was 2.26 [95% confidence interval: 1.19–4.27, p=0.013], HR of C was 1.00 [0.56–1.77, p=0.988], and HR of D was 1.66 [1.11–2.47, p=0.013]. In model 1, HR of B was 2.12 [1.11–4.07, p=0.023], HR of C was 0.99 [0.56–1.75, p=0.964], and HR of D was 1.56 [1.01–2.42, p=0.047]. In model 2, HR of B was 0.95 [0.45–1.97, p=0.897], HR of C was 0.67 [0.35–1.26, p=0.212], and HR of D was [0.25–0.80, p=0.007].

Conclusion

Although slow WS is associated with poor prognosis, the prognosis might be improved if WS increases by 6 months after discharge.

Funding

This study is supported by a Grant-in-Aid for Scientific Research (A) from the Japanese Society for the Promotion of Science [16H01862].

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): The Japanese Society for the Promotion of Science

Perme ICU Mobility Score as a comprehensive assessment tool of acute-phase rehabilitation is correlated with clinical outcomes in patients after cardiovascular surgery

Background

Early mobility therapy in the intensive care unit (ICU) is widely employed to improve the physical function and prognosis of patients with critically ill. On the other hand, patients who undergo cardiovascular surgery frequently suffer from disabilities after ICU care due to their cardiopulmonary conditions and treatments. However, few studies have reported the procedures and assessments of acute-phase rehabilitation in these patients. Recently, the Perme ICU Mobility Score (Perme Score) was developed as a reliable tool to assess comprehensive mobility status of patients in the ICU. We hypothesised that the Perme Score is a useful tool for assessing the mobility levels in the ICU and predicting clinical outcomes in patients undergoing acute-phase rehabilitation after cardiovascular surgery.

Purpose

To investigate the associations between the Perme Score within the second days after cardiovascular surgery and the patients' clinical outcomes, including physical function and the incidence of clinical events.

Methods

We studied 224 consecutive patients (34.4% female; aged 65±13 years) who were admitted to the ICU of a tertiary academic hospital after cardiac and/or major vascular surgery. Clinical characteristics including patient profiles, comorbidities, surgical details and APACHE II and SOFA scores were evaluated on ICU admission. The Perme Score contains categories on mental status, potential mobility barriers, muscle strength and mobility level, with higher scores indicating greater activity levels in the ICU. We assessed the Perme Score within the second days after the surgery. As a physical function at hospital discharge, we measured the six-minute walk distance (6MWD). The primary endpoint was a composite outcome of the number of all-cause mortality and/or all-cause unplanned readmission. We analysed the associations of the Perme Score with the 6MWD and the incidence of clinical events using multiple regression analysis and multivariate Poisson regression analysis, respectively.

Results

After adjusting for clinical confounding factors, a higher Perme Score was an independent factor of a higher 6MWD (Table 1). During the median follow-up period of 1.3 years, 51 cases of all-cause mortality/readmission occurred in 37 (16.5%) patients, with an incidence rate of 18.6/100 person-years. In the multivariate Poisson regression analysis, even after adjusting for the severity score in the ICU, a higher Perme Score was significantly and independently associated with lower rates of all-cause clinical events (adjusted incident rate ratio: 0.96, 95% confidence interval: 0.93–0.99, P=0.008, Figure 1).

Conclusions

The Perme Score within the second days after cardiovascular surgery is correlated with physical function at hospital discharge and the incidence of clinical events after discharge. Thus, a comprehensive assessment of acute-phase rehabilitation after cardiovascular surgery may be useful in predicting clinical outcomes.

Funding Acknowledgement

Type of funding sources: None.

Cancer as a risk factor for physical dysfunction and poor prognosis in patients with cardiovascular disease

Introduction

The emerging interdisciplinary field of cardio-oncology is of interest to clinicians because a history of cancer or cancer treatment is considered a severe risk factor for cardiovascular disease (CVD). Both cancer and CVD can reduce skeletal muscle mass; together, they can lead to a poorer prognosis. However, it is unclear whether a patient's cancer history can lower physical function and lead to a poor prognosis with the coexistence of cancer history and physical dysfunction in patients with CVD. This study aimed to identify the relationship between cancer history and physical function, as well as the prognostic value of their combination, in patients with CVD.

Methods

We reviewed 3,640 patients with CVD (mean age, 67.9±13.5 years) who underwent physical-function tests (gait speed and 6-min walking distance [6MWD]). We performed multivariate linear regression analysis to assess potential associations between cancer history and physical-function tests in patients with CVD. Additionally, we used the Kaplan–Meier curve and Cox regression analyses to assess survival and prognostic significance for patients divided into four groups according to the presence or absence of cancer history and high or low physical function.

Results

In multivariate linear regression analysis, cancer history was independently associated with lower gait speed and 6MWD (gait speed, P=0.048 and 6MWD, P=0.040). A total of 581 deaths occurred over a median follow-up period of 3.08 years (interquartile range: 1.36–5.27). For all-cause mortality, patients with a history of cancer and reduced physical function were found to have a significantly higher mortality risk even after adjusting for several covariates (gait speed, HR: 1.66, P=0.003 and 6MWD, HR: 1.71, P=0.003).

Conclusion

Cancer history was correlated with physical dysfunction in patients with CVD. Moreover, the coexistence of cancer history and physical dysfunction resulted in poorer prognosis in patients with CVD.

Funding Acknowledgement

Type of funding sources: None.

Sex differences in frequency of instrumental activities of daily living after cardiac rehabilitation and its impact on long-term mortality in patients with heart failure

Introduction

While the major outcome of cardiac rehabilitation for heart failure (HF) is the improvement of exercise tolerance, prognosis, and quality of life, instrumental activities of daily living (IADL) has also been focused on as one of the its outcomes. IADL has been reported to be associated with all-cause mortality and quality of life in community-dwelling people and in patients with stable heart disease, but no report has examined the relationship between IADL after cardiac rehabilitation for HF and prognosis. In addition, it is assumed that sex differences may affect the frequency of performing each component of IADL, but there are no reports examining the association with prognosis by sex.

Purpose

The present study aimed to investigate the sex differences in frequency of IADL and its impact on outcomes.

Methods

We retrospectively studied 490 consecutive patients who were admitted due to acute decompensated HF and participated in outpatient cardiac rehabilitation after discharge. The study was performed in accordance with the tenets of the Declaration of Helsinki, and the protocol was approved by the Ethics Committee of our institution. IADL frequency was assessed using the questionnaire-based Frenchay Activities Index (FAI). The primary endpoint was all-cause death and secondary endpoint was combined events (all-cause death and/or readmission due to HF). We performed the Kaplan–Meier and log-rank tests and multivariable Cox regression analysis to evaluate the prognostic predictive capability of the FAI.

Results

The study population had a median age of 69 (interquartile range [IQR]: 58–76) years, and 33.9% of patients were females. The median FAI score was 24 (IQR: 16–29) points. According to the Youden index based on the area under the curve calculated by the receiver operating characteristics curve, the cut-off values of FAI for all-cause death in all-over, females, and males were 23, 22, and 23 points, respectively. Over a median follow-up period of 4.8 years (IQR: 2.3–6.6 years), all-cause death and combined events were occurred in 95 (19.4%) and 213 (43.5%), respectively. After adjustment for several pre-existing prognostic factors, IADL assessed by the FAI was independently associated with all-cause mortality (hazard ratio [HR]: 0.961, 95% confidence interval [CI]:0.937–0.986) and combined events (HR: 0.968, 95% CI: 0.952–0.985), respectively. In addition, there was no interaction between sex in prognostic capability (P=0.664).

Conclusion

Lower IADL frequency assessed by FAI at the end of outpatient cardiac rehabilitation was shown to be associated with poorer prognosis in patients with HF, regardless of sex. The IADL level is generally higher in females than in males but seems to be a useful marker for risk stratification at the end of cardiac rehabilitation in both females and males.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Grant-in-Aid [JSPS KAKENHI Grant Number JP 19K19884]

Impact of small-airway disease on exercise intolerance and long-term outcomes in patients with heart failure and reduced or preserved ejection fraction

Introduction

Exercise intolerance in patients with heart failure (HF) is a strong indicator of a poor prognosis. As the respiratory impairment in HF patients, the small airway is reportedly more susceptible than central airways, which results in increased airway resistance and may cause poor outcomes. However, the impact of small-airway disease (SAD) on exercise intolerance and prognosis in patients with HF is still unclear.

Purpose

We investigated the associations between SAD and exercise intolerance in patients with HF, and the clinical significance of SAD for long-term clinical events with a reduced or preserved ejection fraction.

Methods

We reviewed 1015 patients with HF (mean age, 66.9±14.6 years; male, 64.5%) admitted for medical treatment. Patients with a prior history of chronic respiratory disease or an obstructive lung pattern – defined as the forced expiratory volume (%) in 1 s relative to &lt;70% forced vital capacity using spirometry – were excluded. Characteristics including HF aetiology, comorbidities conditions, medications, blood parameters, and echocardiographic variables were obtained from clinical records. All patients underwent spirometry at hospital discharge, and SAD was defined as the maximum mid-expiratory flow (%) relative to a &lt;60% predicted value. At hospital discharge, we measured 6-min walk distance (6MWD), and &lt;300 m was considered as exercise intolerance. The primary endpoint was a composite clinical event of all-cause death and/or unplanned readmission for HF. Multivariate logistic regression analysis was used to assess the association between SAD and exercise intolerance. The multivariate Cox proportional hazard model was used to clarify whether SAD was an independent predictor for the incidence of clinical events. We also performed subgroup analyses in each multivariate analysis based on a left ventricular ejection fraction (LVEF) of 40%.

Result

SAD was observed in 479 (47.2%) patients. LVEF subgroups included 458 (45.1%) and 518 (51.0%) patients with LVEF &lt;40% and ≥40%, respectively. After adjusting for clinical characteristics, SAD was independently associated with 6MWD &lt;300 m (Figure 1). Moreover, this association was consistently observed in the LVEF &lt;40% and ≥40% (Figure 1). During the median follow-up period of 1.5 years, all-cause death/readmission occurred in 431 patients (42.5%), and the incidence rate was 17.5/100 person-years. In the multivariate Cox proportional hazard model, SAD was independently associated with lower event-free survival rates in all patients and the LVEF &lt;40% subgroup, but not LVEF ≥40% subgroup (Figure 2A, B, and C, respectively).

Conclusion

This study is the first to reveal that SAD is associated with exercise intolerance in patients with HF regardless of LVEF. Moreover, SAD may have a predictive significance for long-term outcomes in patients with HF and subgroups with reduced, but not preserved ejection fraction.

Funding Acknowledgement

Type of funding sources: None.

ACTIVATION OF HUMAN FIBROBLASTS BY CHRONIC RADIATION RATHER THAN ACUTE RADIATION

Cancer-associated fibroblast (CAF), an activated type of fibroblast, is a major stromal cell that contributes to tumor initiation and development in the tumor microenvironment (TME). We previously reported that fractionated radiation rather than acute radiation causes progressive damage to mitochondria and increases the generation of reactive oxygen species, playing an important role in the fibroblast activation in normal tissue injury. Activated fibroblasts then become CAF by interacting with tumor cells, promoting tumor growth in vivo. We here examined the chronic radiation effect on fibroblast activation. Acute radiation (<2.5 Gy) did not increase alpha-Smooth muscle actin, a CAF marker expression in healthy human cells, whereas chronic radiation (2.5 Gy) did. It can be concluded that the induction of fibroblast activation changes across acute radiation, fractionated radiation, and chronic radiation depending on the irradiation technique. This study highlights that radiation activates fibroblasts, playing a role in radiation-related tumor development via TME formation.

Changes in the proportion of anemia among young women after the Great East Japan Earthquake: the Fukushima health management survey

This study aimed to evaluate the sequential changes in the proportion of anemia among young women over eight years after the Great East Japan Earthquake in 2011 using a prospective study of the Fukushima Health Management Survey. This study focused on the women aged between 20 and 44 who lived in the evacuation area of the nuclear power plant accident. The yearly age-adjusted proportion of anemia was accessed with data between July 2011 and March 2019. A total of 9,198 women participated in the health checkup in 2011, albeit the participation was decreased to 1,241 in 2018. The age-adjusted proportion of anemia was 16.7% in 2012 and then declined after 2013 (p with Cochran-Armitage trend test = 0.03). The multivariate regression analysis identified < 23 kg/m² of body mass index (BMI), no history of smoking, and no habitual alcohol use as independent baseline characteristics predictive of temporality anemic condition after the disaster (Adjusted odds ratios [95% confidence interval]; 1.98 [1.43-2.74], 1.85 [1.21-2.83], and 1.42 [1.07-1.90], respectively). Thus, women with low BMI and healthier habits might risk temporarily anemic status after the disaster. Our findings signal the importance of preventing anemia in young women after the disaster.

Relationship between the spread of coronavirus disease 2019, social frailty and depressive symptoms in patients with heart failure

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): the Japan Society for the Promotion of Science (JSPS) KAKENHI

Background

Owing to the spread of coronavirus disease 2019 (COVID-19), people have refrained from going out unnecessarily and have been maintaining social distance. These new lifestyle approaches have affected people physically, psychologically, and socially. Patients with heart failure (HF) are more likely to have social frailty, physical frailty, cognitive impairment, and depressive symptoms, and an overlap of these conditions leads to adverse events. Therefore, multi-domain assessment and understanding of the condition of patients with HF are important for disease management. The spread of COVID-19 is a predicted risk factor for these events, but its impact in patients with HF has not been investigated.

Purpose

We investigated whether the spread of COVID-19 is associated with the development of the multi-domain of frailty in patients with HF.

Methods

Patients who were independent in their daily activities before admission were included in the study. The presence of social frailty (Makizako’s five items), physical frailty (Fried phenotype model), cognitive impairment (Mini-Cog), and depressive symptoms (the Patient Health Questionnaire-2) in patients with HF were assessed at hospital discharge. Logistic regression analyses were used to examine the impact of the spread of COVID-19 on the development of the multi-domain of frailty in patients with HF.

Results

We included 482 patients in this study. Median patient age was 74 years, and 64.5% were male. In multivariate logistic regression analyses, the spread of COVID-19 was significantly associated with the development of social frailty (odds ratio [OR]: 1.15, 95% confidence interval [CI]: 1.02–1.30) and depressive symptoms (OR: 1.14, 95% CI: 1.02–1.27) but not with the development of physical frailty (OR: 1.24, 95% CI: 0.51–3.02) and cognitive impairment (OR: 1.72, 95% CI: 0.80–3.73).

Conclusion

The spread of COVID-19 was associated with the development of social frailty and depressive symptoms in patients with HF. Evaluation of social frailty and depressive symptoms during hospitalization would support disease management and understand their social and psychological conditions specific to the spread of COVID-19.

Prevalence of metabolic dysfunction-associated fatty liver disease and its association with physical function in patients with acute coronary syndrome

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): JSPS KAKENHI

Background

It is widely known that patients with acute coronary syndrome (ACS) are at increased risk of nonalcoholic fatty liver disease (NAFLD), which is linked to sarcopenia and physical dysfunction. However, the relationship between metabolic dysfunction-associated fatty liver disease (MAFLD) and physical dysfunction remains unclear.

Purpose

The purpose of this study was to investigate the prevalence of MAFLD in patients with ACS to assess the relationship between MAFLD and muscle strength, walking speed, and 6-minute walking distance (6 MWD).

Methods

We reviewed patients with ACS who were assessed for hepatic steatosis using the fatty liver index, and the results were further assessed to determine the presence of MAFLD. Multiple regression analysis was used to examine the association between MAFLD and physical function.

Results

Among 479 enrolled hospitalized patients, MAFLD was identified in 234 (48.9%) patients. We conducted a multiple regression analysis in which MAFLD was independently associated with lower leg strength, gait speed, and 6 MWD (leg strength, P = 0.023; gait speed, P = 0.002 and 6 MWD, P = 0.017). Furthermore, having more metabolic impairment was still associated with lower physical function decline (leg strength, P for trend = 0.002; gait speed, P for trend = 0.019 and 6 MWD, P for trend = 0.003).

Conclusions

MAFLD is common in hospitalized patients with ACS, and most patients with MAFLD have many overlapping metabolic abnormalities. MAFLD is associated with impaired physical function, and the greater the number of overlapping metabolic abnormalities, the worse the motor function.