A preliminary report on retrospective dose assessment by FISH translocation assay in FDNPP Nuclear Emergency Worker Study (NEWS).

In Japan, a national project of longitudinal health care and epidemiological research (NEWS) was developed in 2014 to analyse the effects of radiation on human health for workers who responded to the Fukushima Dai-ichi nuclear emergency in 2011. In 2018, peripheral blood for chromosome translocation analysis was collected from 62 workers. Retrospective dose assessment was performed with fluorescence in situ hybridisation translocation (FISH-Tr) assay. The range of estimated doses by FISH-Tr assay was 0-635 mGy, in which 22 workers had estimated doses of more than 189 mGy. Biological dose estimates were five times higher in workers with physically measured total exposure recordings above 70 mGy. It is likely that smoking and medical exposure caused the discrepancy between estimated biological and physical total exposure doses. Thus, there is a possibility that retrospective biodosimetry assessment might over-estimate occupational exposures to workers exposed to chronic radiation during nuclear emergency work.

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.

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.

Automated Endocardial Border Detection and Left Ventricular Functional Assessment in Echocardiography Using Deep Learning.

Endocardial border detection is a key step in assessing left ventricular systolic function in echocardiography. However, this process is still not sufficiently accurate, and manual retracing is often required, causing time-consuming and intra-/inter-observer variability in clinical practice. To address these clinical issues, more accurate and normalized automatic endocardial border detection would be valuable. Here, we develop a deep learning-based method for automated endocardial border detection and left ventricular functional assessment in two-dimensional echocardiographic videos. First, segmentation of the left ventricular cavity was performed in the six representative projections for a cardiac cycle. We employed four segmentation methods: U-Net, UNet++, UNet3+, and Deep Residual U-Net. UNet++ and UNet3+ showed a sufficiently high performance in the mean value of intersection over union and Dice coefficient. The accuracy of the four segmentation methods was then evaluated by calculating the mean value for the estimation error of the echocardiographic indexes. UNet++ was superior to the other segmentation methods, with the acceptable mean estimation error of the left ventricular ejection fraction of 10.8%, global longitudinal strain of 8.5%, and global circumferential strain of 5.8%, respectively. Our method using UNet++ demonstrated the best performance. This method may potentially support examiners and improve the workflow in echocardiography.

Association Between Lifestyle Habits and the Prevalence of Abdominal Obesity After the Great East Japan Earthquake: The Fukushima Health Management Survey.

BACKGROUND: The proportion of overweight individuals living in the evacuation zone of Fukushima increased after the Great East Japan Earthquake. However, the change in the prevalence of abdominal obesity has not been reported. Lifestyle habits and changes in these habits after the disaster might have affected the onset of abdominal obesity; however, the association between the two is unclear. METHODS: This study evaluated 19,673 Japanese participants of the Fukushima Health Management Survey. We used data from general health check-ups conducted in 13 municipalities between 2008 and 2010. Follow-up examinations were performed from June 2011 to March 2013. Changes in the proportion of individuals with abdominal obesity before and after the disaster were compared. Then, lifestyle habits affecting these changes were assessed. RESULTS: We found that 34.2% and 36.6% of participants (P < 0.001), both evacuees (37.0% and 42.1% [P < 0.001]) and non-evacuees (32.8% and 34.0% [P < 0.001]), had abdominal obesity before and after the disaster, respectively. Abdominal obesity was positively associated with smoking cessation, snacking after dinner, and non-breakfast skipping after the disaster and alcohol drinking before and after the disaster (all P < 0.05). Smoking cessation was positively associated with abdominal obesity in both evacuees and non-evacuees and in both men and women (all P < 0.01). CONCLUSION: The prevalence of abdominal obesity increased among residents in the area affected by nuclear disaster. It might be associated with not only lifestyle habits before the disaster but also changes in these habits after the disaster, especially smoking cessation.

Does chemical shift imaging offer a biomarker for the diagnosis and assessment of disease severity in multiple myeloma?: A cross-sectional study.

ABSTRACT: To investigate whether chemical shift imaging (CSI) is useful for differentiating myelomatous infiltration from hematopoietic bone marrow (BM) and for quantitatively assessing disease severity.In this retrospective study, spinal MRI, including a sagittal iterative decomposition of water and fat with echo asymmetry and least-squares estimation T2 fast spin-echo sequence, was performed on 76 myeloma patients (45 men, 67.0 ±â€Š11.4 years; 31 women, 66.5 ±â€Š11.0 years) and 30 control subjects (20 men, 67.0 ±â€Š8.4 years; 10 women, 67.0 ±â€Š9.2 years). The fat-signal fraction (FF) and mean signal dropout ratio (DR) were calculated from lumbar BM that contained no focal lesions. The BM plasma cell percentage (BMPC%) and serological data were obtained. As DR is highest when FF = 50%, the patients were divided into 2 groups: a water-dominant group (FF < 50%) and a fat-dominant group (FF > 50%).Serum monoclonal protein (M protein), ß2-microglobulin, and BMPC% were significantly higher in the water-dominant group than in the fat-dominant group. In the water-dominant group, DR correlated significantly with BMPC% and M protein, whereas in the control group, DR showed a weak correlation with age but no correlation with other clinical factors. No significant differences in any clinical data were seen between high and low DR.CSI proved ineffective for differentiating myelomatous infiltration from hematopoietic BM. For myeloma patients with relatively high BM cellularity, a small signal drop on opposed-phase images indicated a higher tumor burden. For BM with relatively low cellularity, disease severity was not reflected by CSI.

Influence of post-disaster evacuation on incidence of hyperuricemia in residents of Fukushima Prefecture: the Fukushima Health Management Survey.

AIM: After the Great East Japan Earthquake, over 160,000 residents in Fukushima Prefecture were forced to evacuate the area around the Fukushima Daiichi power plant following nuclear accident there. Health problems in these evacuees have since become a major issue. We have examined the association between evacuation and incidence of hyperuricemia among residents in Fukushima. METHODS: We conducted a cohort study of residents aged 40-90 years without hyperuricemia at the time of the Fukushima disaster. Among 8173 residents who met the inclusion criteria before the disaster, 4789 residents (men: 1971, women: 2818; follow-up duration: 1.38 years; and follow-up rate: 58.6%) remained available for follow-up examinations at the end of March 2013. The main endpoint was incidence of hyperuricemia, defined by the Japanese committee guidelines, using local health data from before and after the disaster. We divided participants by evacuation status and compared outcomes between groups. Using a logistic regression model, we estimated the odds ratio for incidence of hyperuricemia, adjusting for potential confounders, age, gender, waist circumference, physical activity, and alcohol consumption. RESULTS: Incidence of hyperuricemia was higher in evacuees (men 10.1%; women 1.1%) than in non-evacuees (men 7.4%, women 1.0%). Evacuees had higher body mass index, waist circumference, triglycerides, LDL-cholesterol, fasting plasma glucose, HbA1c, and lower HDL-cholesterol after the disaster than non-evacuees. We found that evacuation was associated with incidence of hyperuricemia (adjusted odds ratio: 1.38; 95% confidence interval: 1.03-1.86). CONCLUSION: This is the first study to demonstrate an association between evacuation after a disaster and increased incidence of hyperuricemia.

The impact of evacuation on the incidence of chronic kidney disease after the Great East Japan Earthquake: The Fukushima Health Management Survey.

BACKGROUND: About 146,000 people were forced into long-term evacuation due to the nuclear power plant accident caused by the Great East Japan Earthquake in 2011. Disaster is known to induce hypertension in survivors for a certain period, but it is unclear whether prolonged disaster stress influences chronic kidney disease (CKD). We conducted an observational cohort study to elucidate the effects of evacuation stress on CKD incidence. METHODS: Participants were individuals living in communities near the Fukushima nuclear power plant, aged 40-74 years without CKD as of their 2011 general health checkup (non-evacuees: n = 9780, evacuees: n = 4712). We followed new-onset CKD [estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m2 or proteinuria] using general annual health checkup data from 2012 to 2014. Association between evacuation and CKD incidence was analyzed using the Cox proportional hazard model. RESULTS: Mean age of the participants at baseline was 65 years, 46.7% were men, and baseline eGFR was 75.7 ml/min/1.73 m2. During the mean follow-up period of 2.46 years, CKD incidence rate was 80.8/1000 and 100.2/1000 person-years in non-evacuees and evacuees, respectively. Evacuation was a significant risk factor of CKD incidence after adjusting for age, gender, obesity, hypertension, diabetes, dyslipidemia, smoking, and baseline eGFR [hazard ratio (HR): 1.45; 95% confidence interval (CI) 1.35-1.56]. Evacuation was significantly associated with the incidence of eGFR <60 ml/min/1.73 m2 (HR: 1.48; 95% CI 1.37-1.60), but not with the incidence of proteinuria (HR: 1.21; 95% CI 0.93-1.56). CONCLUSION: Evacuation was a risk factor associated with CKD incidence after the disaster.

Prevalence of Renal Dysfunction among Evacuees and Non-evacuees after the Great East Earthquake: Results from the Fukushima Health Management Survey.

Objective We conducted the present study to evaluate the prevalence of chronic kidney disease (CKD) and CKD complications among evacuees and non-evacuees after the Great East Japan Earthquake and Fukushima Daiichi nuclear disaster. Methods Twenty-seven thousand and eighty-eight subjects who were living near the Fukushima Daiichi Nuclear Power Plant in Fukushima Prefecture in Japan, aged ≥40 years by the Heath Care Insures, were included in the analyses. Metabolic factors were compared between the evacuees and non-evacuees stratified by the eGFR and proteinuria grades. Results The prevalence of CKD with a low eGFR (<60 mL/min/1.73 m(2)) and proteinuria were 21.59% and 1.85%, respectively. The risk of CKD complications was classified into four grades according to the eGFR and proteinuria grades. The prevalence of diabetes, hypertension, and dyslipidemia were significantly higher in the very high risk group than in the low risk group. The prevalence of diabetes and dyslipidemia were significantly higher in evacuees than in non-evacuees in only the low risk group. However, a multivariate logistic regression analysis showed that evacuation was not significantly associated with the risk of a low eGFR or proteinuria. Conclusion This study did not reach the definitive conclusion that evacuation elevated the risk of CKD complication, although evacuation might lead to increased CKD complications in the future. We believe that this information is important for follow-up and lifestyle change recommendations for evacuees.

Comparison of childhood thyroid cancer prevalence among 3 areas based on external radiation dose after the Fukushima Daiichi nuclear power plant accident: The Fukushima health management survey.

The 2011 Great East Japan Earthquake led to a subsequent nuclear accident at the Fukushima Daiichi Nuclear Power Plant. In its wake, we sought to examine the association between external radiation dose and thyroid cancer in Fukushima Prefecture. We applied a cross-sectional study design with 300,476 participants aged 18 years and younger who underwent thyroid examinations between October 2011 and June 2015. Areas within Fukushima Prefecture were divided into three groups based on individual external doses (≥1% of 5 mSv, <99% of 1 mSv/y, and the other). The odds ratios (ORs) and 95% confidence intervals of thyroid cancer for all areas, with the lowest dose area as reference, were calculated using logistic regression models adjusted for age and sex. Furthermore, the ORs of thyroid cancer for individual external doses of 1 mSv or more and 2 mSv or more, with the external dose less than 1 mSv as reference, were calculated. Prevalence of thyroid cancer for the location groups were 48/100,000 for the highest dose area, 36/100,000 for the middle dose area, and 41/100,000 for the lowest dose area. Compared with the lowest dose area, age-, and sex-adjusted ORs (95% confidence intervals) for the highest-dose and middle-dose areas were 1.49 (0.36-6.23) and 1.00 (0.67-1.50), respectively. The duration between accident and thyroid examination was not associated with thyroid cancer prevalence. There were no significant associations between individual external doses and prevalence of thyroid cancer. External radiation dose was not associated with thyroid cancer prevalence among Fukushima children within the first 4 years after the nuclear accident.

Increased prevalence of atrial fibrillation after the Great East Japan Earthquake: Results from the Fukushima Health Management Survey.

BACKGROUND: Previous studies have shown that control of cardiovascular risk factors deteriorates among residents after a natural disaster. This study assessed the hypothesis that the prevalence of atrial fibrillation (AF) increased among residents in the evacuation zone of Fukushima prefecture after the Great East Japan Earthquake. METHODS AND RESULTS: This longitudinal study examined subjects aged 40-90 years using data collected from 26,163 participants (11,628 men and 14,535 women) sourced from general health checkups conducted in twelve communities, including the evacuation zone specified by the government, between 2008 and 2010. The study obtained 12-lead ECG tracings and conducted follow-up examinations from June 2011 to the end of March 2013. A total of 12,410 participants (5704 men and 6706 women, follow-up proportion: 47%) received follow-up examinations after the earthquake, with an average follow-up of 1.4 years. The prevalence of AF increased among participants after the earthquake (before: 1.9% vs. after: 2.4%, P<.001). During the follow-up period, 79 incidences of AF occurred among participants. Excess ethanol intake (≥44 g/day) and obesity showed associations with an increased risk of AF after the earthquake, with multivariable-adjusted hazard ratios (95% confidence interval) of 3.07 (1.55-6.08) and 1.87 (1.19-2.94), respectively. CONCLUSIONS: The prevalence of AF increased among residents in the evacuation zone of Fukushima prefecture after the Great East Japan Earthquake, with excess alcohol intake and obesity associated with an increased risk of AF.

Prevalence of ectopic intrathyroidal thymus in Japan: the Fukushima health management survey.

BACKGROUND: Ectopic intrathyroidal thymus is thought to be a rare entity, often discovered incidentally, and is due to aberrant thymic migration during embryogenesis. OBJECTIVE: The aim of this study was to determine the prevalence of ectopic intrathyroidal thymus in children using ultrasound screening. METHODS: This study was cross-sectional and was conducted with the initial preliminary survey of the Fukushima Health Management Survey between October 9, 2011, and March 31, 2012, after the Fukushima Daiichi Nuclear Power Plant accident. A total of 37,816 children were examined in the survey. RESULTS: Diagnostic criteria are based on the ultrasonographic appearance of ectopic intrathyroidal thymus, which were round, oval, or polygonal hypoechoic or hyperechoic areas, with multiple granular and punctate echogenic foci. A total of 375 (0.99%) cases (164 girls) with ectopic intrathyroidal thymus were observed. The mean age was 7.0 years (range 0-18 years). Ectopic intrathyroidal thymus was located in the right (n=180), left (n=178), or bilateral (n=17) thyroid lobes. The incidence of ectopic intrathyroidal thymus was inversely correlated with age and body mass index. CONCLUSION: The results reflect the prevalence of ectopic intrathyroidal thymus using ultrasonography in the general population. Further examination will be needed by way of longitudinal follow-up.