Demonstrating the undermining of science and health policy after the Fukushima nuclear accident by applying the Toolkit for detecting misused epidemiological methods

It is well known that science can be misused to hinder the resolution (i.e., the elimination and/or control) of a health problem. To recognize distorted and misapplied epidemiological science, a 33-item "Toolkit for detecting misused epidemiological methods" (hereinafter, the Toolkit) was published in 2021. Applying the Toolkit, we critically evaluated a review paper entitled, "Lessons learned from Chernobyl and Fukushima on thyroid cancer screening and recommendations in the case of a future nuclear accident" in Environment International in 2021, published by the SHAMISEN (Nuclear Emergency Situations - Improvement of Medical and Health Surveillance) international expert consortium. The article highlighted the claim that overdiagnosis of childhood thyroid cancers greatly increased the number of cases detected in ultrasound thyroid screening following the 2011 Fukushima nuclear accident. However, the reasons cited in the SHAMISEN review paper for overdiagnosis in mass screening lacked important information about the high incidence of thyroid cancers after the accident. The SHAMISEN review paper ignored published studies of screening results in unexposed areas, and included an invalid comparison of screenings among children with screenings among adults. The review omitted the actual state of screening in Fukushima after the nuclear accident, in which only nodules > 5 mm in diameter were examined. The growth rate of thyroid cancers was not slow, as emphasized in the SHAMISEN review paper; evidence shows that cancers detected in second-round screening grew to more than 5 mm in diameter over a 2-year period. The SHAMISEN consortium used an unfounded overdiagnosis hypothesis and misguided evidence to refute that the excess incidence of thyroid cancer was attributable to the nuclear accident, despite the findings of ongoing ultrasound screening for thyroid cancer in Fukushima and around Chernobyl. By our evaluation, the SHAMISEN review paper includes 20 of the 33 items in the Toolkit that demonstrate the misuse of epidemiology. The International Agency for Research on Cancer meeting in 2017 and its publication cited in the SHAMISEN review paper includes 12 of the 33 items in the Toolkit. Finally, we recommend a few enhancements to the Toolkit to increase its utility

Factors affecting the choice of suicide method in Okayama: a database analysis from a forensic perspective

The annual number of suicides in Japan increased sharply in 1998, and since that time it has consistently exceeded 30,000 per year. In this study, we analyze a database of personal and background characteristics of 824 cases (605 men, 219 women) who completed suicide in Okayama Prefecture in 2002 and 2003. The data were obtained with cooperation from the police. Using the methodologies in a previous European study as a model, we classified the suicide methods into 8 categories. To examine the generational and regional differences in the choice of methods, we stratified the sample into 4 age groups (&#60;-24, 2544, 4564, and &#62;-65) and 2 regional groups (Okayama/Kurashiki vs. other areas). Our results on gender differences in 7 of the suicide methods were mostly similar to the European data. However, our data showed a remarkably higher proportionate male-to-female mortality ratio for poisoning by other substances (ICD-10, X65-X69 codes) (1.83, 1.15-2.92). In terms of generational differences in the choice of suicide methods, the Mantel-Haenszel test of homogeneity was significant for most of the categories in our study, suggesting an impact of age on how people commit suicide. There were no remarkable regional differences in our sample. An epidemic curve for suicides via carbon monoxide poisoning using charcoal briquets revealed a trend of time clustering not observed in the other 6 means. The database constructed and used in this study contains richer information than conventional death statistics and is expected to provide helpful knowledge and insights for future epidemiological studies.</p

加齢またはアルツハイマー病が語彙・意味機能に及ぼす影響 : 意味的プライミング法による検討

This study aims to clarify the influences of aging and AD on lexical-semantics by assigning a semantic priming paradigm. The following participants are included in the study: 30 young students, 22 early elderly, 19 late elderly, and 14 AD patients. The participants are asked to perform lexical decision tasks. Targets are high-frequency concrete words or nonwords. The primes are controlled with regard to their semantic relevance to the targets as follows: Association (e.g., king - lion), Superordination (beast - lion), Coordination (tiger - lion), Shared feature (eyes - lion), Distinctive feature (mane - lion), or Neutral (XXXX – lion). The participants have to decide whether the stimulus is a real word or not as correctly and as quickly as possible when the targets appeared on a monitor. As the Results, the mean reaction times (RTs) of the elderly groups are significantly longer than those of the young group, and the RTs of the AD group are even longer than those of the elderly groups. In the young and the elderly groups, the RTs for all the related-prime conditions are significantly shorter than those for the neutral-prime conditions (priming effects). The priming effects appears to be greater in the elderly groups. However, when the RTs are taken into consideration (priming rates), the gains are equivalent among young and elderly groups. In the AD group, priming effects are not observed, and noticeable individual differences in the priming rate are seen. The above findings suggest that lexical-semantics are generally preserved from aging. We also discusses that lexical-semantics are impaired in AD, and the diversity of the impairments may be the essence of AD

Thyroid Cancer Detection by Ultrasound Among Residents Ages 18 Years and Younger in Fukushima

Background: After the Great East Japan Earthquake and Tsunami in March 2011, radioactive elements were released from the Fukushima Daiichi Nuclear Power Plant. Based on prior knowledge, concern emerged about whether an increased incidence of thyroid cancer among exposed residents would occur as a result. Methods: After the release, Fukushima Prefecture performed ultrasound thyroid screening on all residents ages <=18 years. The first round of screening included 298,577 examinees, and a second round began in April 2014. We analyzed the prefecture results from the first and second round up to December 31, 2014, in comparison with the Japanese annual incidence and the incidence within a reference area in Fukushima Prefecture. Results: The highest incidence rate ratio, using a latency period of 4 years, was observed in the central middle district of the prefecture compared with the Japanese annual incidence (incidence rate ratio = 50; 95% confidence interval [CI] = 25, 90). The prevalence of thyroid cancer was 605 per million examinees (95% CI = 302, 1,082) and the prevalence odds ratio compared with the reference district in Fukushima Prefecture was 2.6 (95% CI = 0.99, 7.0). In the second screening round, even under the assumption that the rest of examinees were disease free, an incidence rate ratio of 12 has already been observed (95% CI = 5.1, 23). Conclusions: An excess of thyroid cancer has been detected by ultrasound among children and adolescents in Fukushima Prefecture within 4 years of the release, and is unlikely to be explained by a screening surge

Effects of the increase in co-payments from 20 to 30 percent on the compliance rate of patients with hypertension or diabetes mellitus in the Employed Health Insurance System

Objectives: How to contain medical expenditures is a universal problem. The Japanese government has increased patient co-payments to control it. The purpose of this study is to clarify whether the increase in co-payments to 30 percent prevented patients with hypertension or diabetes mellitus from receiving necessary care in the Employee Health Insurance System. Methods: The subjects were 211 patients with hypertension and 66 patients with diabetes mellitus who regularly visited physicians from October 2001 to March 2002 and were defined as a cohort that needed health care, and their medical indicators were examined between April and September 2002 (prestage) and between April and September 2003 (poststage). Results: In the hypertensive patients with no complications, the compliance rate was 89.9 percent and 88.0 percent in the prestage, and poststage, respectively, showing no significant change. In the hypertensive patients with complications, the compliance rate was 90.5 percent and 92.1 percent in the prestage and poststage, respectively, showing no significant change. In the diabetic patients with complications, the compliance rate was 77.5 percent and 79.2 percent, in the prestage and poststage, respectively, with no significant change. In the diabetic patients with no complications, however, the compliance rate was 83.7 percent and 66.7 percent, in the prestage and poststage, respectively. A significant decrease was observed among diabetic patients without complications. Conclusions: Increasing co-payments reduced necessary preventive care in diabetic patients without complications.</p

Diarrhea and related personal characteristics among Japanese university students studying abroad in intermediate- and low-risk countries

Despite an increasing number of students studying abroad worldwide, evidence about health risks while they are abroad is limited. Diarrhea is considered the most common travelers' illness, which would also apply to students studying abroad. We examined diarrhea and related personal characteristics among Japanese students studying abroad. Japanese university students who participated in short-term study abroad programs between summer 2016 and spring 2018 were targeted (n = 825, 6-38 travel days). Based on a 2-week-risk of diarrhea (passing three or more loose or liquid stools per day) among travelers by country, the destination was separated into intermediate- and low-risk countries. After this stratification, the associations between personal characteristics and diarrhea during the first two weeks of their stay were evaluated using logistic regression models. Among participants in intermediate-risk countries, teenagers, males and those with overseas travel experience were associated with an elevated risk of diarrhea; the odds ratios (95% confidence intervals) were 2.42 (1.08-5.43) for teenagers (vs. twenties), 1.93 (1.08-3.45) for males (vs. females) and 2.37 (1.29-4.33) for those with overseas experience (vs. none). Even restricting an outcome to diarrhea during the first week did not change the results substantially. The same tendency was not observed for those in the low-risk countries. Teenage students, males and those with overseas travel experience should be cautious about diarrhea while studying abroad, specifically in intermediate-risk countries

Evaluating the Effects of Air Pollution from a Plastic Recycling Facility on the Health of Nearby Residents

We evaluated how exposure to airborne volatile organic compounds emitted from a plastic recycling facility affected nearby residents, in a cross-sectional study. Individuals>10 years old were randomly sampled from 50 households at five sites and given questionnaires to complete. We categorized the subjects by distance from the recycling facility and used this as a proxy measure for pollutant exposure. We sought to improve on a preceding study by generating new findings, improving methods for questionnaire distribution and collection, and refining site selection. We calculated the odds of residents living 500 or 900 m away from the facility reporting mucocutaneous and respiratory symptoms using a reference group of residents 2,800 m away. Self-reported nasal congestion (odds ratio=3.0, 95% confidence interval=1.02-8.8), eczema (5.1, 1.1-22.9), and sore throat (3.9, 1.1-14.1) were significantly higher among residents 500 m from the facility. Those 900 m away were also considerably more likely to report experiencing eczema (4.6, 1.4-14.9). Air pollution was found responsible for significantly increased reports of mucocutaneous and respiratory symptoms among nearby residents. Our findings confirm the effects of pollutants emitted from recycling facilities on residents’ health and clarify that study design differences did not affect the results

Aflatoxins in Rice Artificially Contaminated with Aflatoxin-producing Aspergillus flavus under Natural Storage in Japan

Aflatoxin (AFT) contamination is frequent in foods grown in tropical regions, including rice. Although AFTs are generally not found in temperate-region foods, global warming has affected typical temperate-region climates, potentially permitting the contamination of foods with AFT-producing Aspergillus flavus (A. flavus). Here we investigated the AFT production in rice during storage under natural climate conditions in Japan. We examined AFTs in brown rice and rough rice artificially contaminated with A. flavus for 1 year in Japan, and we subjected AFTs in white rice to the same treatment in airtight containers and examined the samples in warm and cold seasons, simulating the storage of white rice in general households. In the brown rice, AFTs increased after 2 months (March) and peaked after 9 months (October). The AFT contamination in the rough rice was minimal. After the polishing and cooking of the brown rice, AFTs were undetectable. In the white rice stored in airtight containers, AFTs increased after 1 month (August) and peaked after 2 months (September). Minimal AFTs were detected in the cold season. Thus, AFT contamination in rice may occur in temperate regions following A. flavus contamination. The storage of rice as rough rice could provide be useful for avoiding AFT contamination

Methyl Mercury Exposure at Niigata, Japan: Results of Neurological Examinations of 103 Adults

Background. Large-scale poisonings caused by methyl mercury (MeHg) have occurred in Japan (Minamata in the 1950s and Niigata in the 1960s) and Iraq (in the 1970s). The current WHO neurological risk standard for adult exposure (hair level: 50 μg/g) was based partly on evidence from Niigata which did not consider any cases who were diagnosed later and/or exposed to low level of MeHg (hair mercury level less than 50 μg/g). Methods. Early in the Niigata epidemic in June 1965 there were two extensive surveys. From these two surveys, we examined 103 adults with hair mercury measurement who consulted two medical institutions. We compared the prevalence and the distribution of neurological signs related to MeHg poisoning between exposure categories. Result. We found 48 subjects with neurological signs related to MeHg poisoning who had hair mercury concentration less than 50 μg/g. Among the neurological signs, sensory disturbance of the bilateral distal extremities was observed more frequently, followed by disequilibrium, hearing impairment, and ataxia, in groups with hair MeHg concentration both below 50 μg/g and over 50 μg/g. Conclusion. The present study suggests the possibility that exposure to MeHg at levels below the current WHO limits could cause neurologic signs, in particular, sensory disturbance

Effects of an increase in patient copayments on medical service demands of the insured in japan

Objectives:To examine quantitatively the effects of an increase in patient copayments from 10% to 20% on the demand for medical services in Japan. Methods: The subjects of the study were the employees insured by the 1,797 health insurance societies, belonging to the National Federation of Health Insurance Societies, in 1996 and 1998. Indicators of medical service demands analyzed include the inpatient, outpatient, and dental case rates, the number of serviced days per case, the medical cost per day and the medical cost per insured. Results: When the effects of an increase in patient copayments from 10% to 20% were evaluated, taking into account the average age, the average monthly salary, the total number, the gender (male-tofemale) ratio and the dependent ratio of the insured, the estimated change in the case rate was &#8722;6.96% for inpatient, &#8722;4.79% for outpatient, and &#8722;5.77% for dental care. The estimated change in the number of serviced day per case was &#8722;4.66% for inpatient, &#8722;5.67% for outpatient, and &#8722;1.82% for dental care. The estimated change in the medical cost per day was &#8722;3.15% for inpatient, &#8722;13.00% for outpatient, and &#8722;11.48% for dental care. The estimated change in the medical cost per insured was &#8722;14.08% for inpatient, &#8722;21.54% for outpatient, and &#8722;18.11% for dental care. Conclusions: The increase in patient copayments from 10% to 20% enabled insurers to substantially reduce medical costs by cost shifting from the insurer to the insured, with resultant changes in the case rate and the number of service days per case.</p