Machine Learning-Based Prediction of Functional Disability: a Cohort Study of Japanese Older Adults in 2013-2019.

BACKGROUND: It is important to identify older adults at high risk of functional disability and to take preventive measures for them at an early stage. To our knowledge, there are no studies that predict functional disability among community-dwelling older adults using machine learning algorithms. OBJECTIVE: To construct a model that can predict functional disability over 5 years using basic machine learning algorithms. DESIGN: A cohort study with a mean follow-up of 5.4 years. PARTICIPANTS: We used data from the Japan Gerontological Evaluation Study, which involved 73,262 people aged ≥ 65 years who were not certified as requiring long-term care. The baseline survey was conducted in 2013 in 19 municipalities. MAIN MEASURES: We defined the onset of functional disability as the new certification of needing long-term care that was ascertained by linking participants to public registries of long-term care insurance. All 183 candidate predictors were measured by self-report questionnaires. KEY RESULTS: During the study period, 16,361 (22.3%) participants experienced the onset of functional disability. Among machine learning-based models, ridge regression (C statistic = 0.818) and gradient boosting (0.817) effectively predicted functional disability. In both models, we identified age, self-rated health, variables related to falls and posture stabilization, and diagnoses of Parkinson's disease and dementia as important features. Additionally, the ridge regression model identified the household characteristics such as the number of members, income, and receiving public assistance as important predictors, while the gradient boosting model selected moderate physical activity and driving. Based on the ridge regression model, we developed a simplified risk score for functional disability, and it also indicated good performance at the cut-off of 6/7 points. CONCLUSIONS: Machine learning-based models showed effective performance prediction over 5 years. Our findings suggest that measuring and adding the variables identified as important features can improve the prediction of functional disability.

Difficulties in Accessing Medication Records at the Time of a Large-Scale Disaster.

OBJECTIVE: In a large-scale disaster, medical professionals need to access medication records and provide medicines to people who cannot return home to take their daily medicines. We investigated the proportion of carrying the paper notebook or availability of the smartphone application of the medication record among people who are assumed to have difficulty in taking their medicines during large-scale disasters. METHODS: In Japan, a web-based survey was conducted in 2018 by randomly selecting adults ≥ 20 years of age. RESULTS: There were 2286 medication record owners in 3082 participants. Of the medication record owners, 784 (34.3%) took medicines that could not be missed for even a day. Among them, 724 used paper notebooks alone, 26 used smartphone applications alone, and 34 used both. Among the 724, 208 (28.8%) always carried a paper notebook. Among the 26, 16 (61.5%) could use their applications anytime. Therefore, among the 784, at least 560 (71.4%) could not always access their medication information. CONCLUSIONS: An awareness campaign to carry paper notebooks and install applications for medication records should be held, since only a limited number of people carry their medication records and always have access to their medication information.

Concerning perceived and clinically-measured levels of halitosis.

The different types of self-reported halitosis complaints include those where one feels that one's breath smells bad, where one feels that one has bad breath because of the attitudes of others, and where others have pointed out the presence of bad breath. The results of previous studies comparing the objective and subjectives measures of halitosis are inconsistent, and few studies have used gas chromatography (GC) to measure halitosis in a large sample. This study aimed to examine the objectively measured halitosis levels based on the reasons individuals are concerned about halitosis. We included 2063 patients who visited the halitosis clinic at a university dental hospital. Halitosis was assessed using GC, self-administered questionnaires, and oral examinations. Levels of volatile sulphur compounds (VSCs; H2S, CH3SH, and (CH3)2S) were set as objective measures of halitosis. Patients were grouped based on their answers to 'What made you concerned about bad breath?' into groups: 'self-perceived,' 'attitudes of others,' 'told by others,' and other reasons. Univariate and multivariable linear regression analyses were performed to examine factors associated with VSCs and objective halitosis levels. Age, sex, oral health status, smoking, drinking, and breakfast habits were used as confounders. Patients who answered 'told by others' (n= 691, 33.5%) showed the highest VSCs. Individuals whose halitosis was pointed out by others had higher objectively measured halitosis levels, while those concerned about the attitudes of others or perceived their own halitosis had lower objectively measured halitosis levels. These results suggest that the objective level of halitosis can differ on the basis of the reason underlying an individual's concern about their bad breath. Categorizing halitosis complaints and comparing them with objective halitosis levels may help reduce the anxiety of those who are concerned about halitosis and confirm the need for intervention for those with objective halitosis.

Long-Term Trend in the Association Between Disaster Damage and Happiness Before and After the Great East Japan Earthquake.

Objectives: Disasters change survivors' living circumstances, which can affect their happiness. We examined the trends in the association between disaster damage and happiness before and after a disaster. Methods: We analyzed 4,044 participants aged ≥65 years who had experienced the Great East Japan Earthquake in 2011. The baseline survey was conducted 7 months before the disaster. Follow-up surveys have been conducted every 3 years. Using a mixed model for repeated measures, we compared the prevalence ratios (PRs) for unhappiness according to the survivors' level of housing damage, which is a proxy for disaster damage. Results: The unhappiness in participants who suffered severe damage appeared to be higher than in those with no damage in 2010 (multivariate-adjusted PR: 1.18, 95% confidence interval: 0.93-1.48). A higher PR was observed after the earthquake in 2013 (1.34, 0.79-2.28), while there was no difference in 2016 (1.02, 0.53-1.97) and 2019 (1.03, 0.50-2.12). Conclusion: The prevalence of unhappiness in survivors with severe housing damage was higher before the disaster. However, the unhappiness gap between people with and without housing damage converged during the follow-up.

The association between body mass index and recovery from post-traumatic stress disorder after the nuclear accident in Fukushima.

Post-traumatic stress disorder (PTSD) and obesity share common risk factors; however, the effect of obesity on recovery from PTSD has not been assessed. We examined the association between body mass index (BMI) and recovery from PTSD after the Great East Japan Earthquake. We analyzed 4356 men and women with probable PTSD aged ≥ 16 years who were living in evacuation zones owing to the radiation accident in Fukushima, Japan. Recovery from probable PTSD was defined as Post-traumatic Stress Disorder Checklist-specific scores < 44. Using Poisson regression with robust error variance adjusted for confounders, we compared the prevalence ratios (PRs) and 95% confidence intervals (CIs) for this outcome in 2013 and 2014. Compared with point estimates for normal weight (BMI: 18.5-24.9 kg/m2), especially in 2013, those for underweight (BMI: < 18.5 kg/m2) and obesity (BMI: ≥ 30.0 kg/m2) tended to slightly increase and decrease, respectively, for recovery from probable PTSD. The multivariate-adjusted PRs (95% CIs) for underweight and obesity were 1.08 (0.88-1.33) and 0.85 (0.68-1.06), respectively, in 2013 and 1.02 (0.82-1.26) and 0.87 (0.69-1.09), respectively, in 2014. The results of the present study showed that obesity may be a useful predictor for probable PTSD recovery. Obese victims with PTSD would require more intensive support and careful follow-up for recovery.

Does variety of social interactions associate with frequency of laughter among older people? The JAGES cross-sectional study.

OBJECTIVE: Several studies have reported that laughter is associated with health benefits. In addition, social interactions, such as social relationships, social participation and so forth, have shown the association with not only health but also individual emotion. In this study, we conducted a cross-sectional study to examine the association between variety of social interactions and the frequency of laughter. DESIGN: Cross-sectional study. SETTING: Sampled from 30 municipalities in Japan. PARTICIPANTS: Non-disabled Japanese men (n=11 439) and women (n=13 159) aged ≥65 years using data from the Japan Gerontological Evaluation Study, which was conducted during October to December in 2013. PRIMARY OUTCOME MEASURES: Laughing almost every day by self-reported questionnaire. RESULTS: Poisson regression analysis with robust error variance was used to calculate prevalence ratios (PRs) for laughing almost every day according to each social relationship and its potential community-level environmental determinants. The prevalence of laughing almost every day tended to increase with increased variety in each social interaction after adjusting, instrumental activities of daily living, number of living together, working status, depression, self-reported economic status and residence year. Among men and women, multivariate-adjusted PRs (95% CIs) by comparing participants with the highest and lowest categories were 1.18 (1.04 to 1.35) and 1.16 (1.04 to 1.29) in positive life events; 1.26 (1.10 to 1.45) and 1.09 (0.96 to 1.24) in perceived positive changes in the area; 1.15 (1.04 to 1.28) and 1.17 (1.07 to 1.28) in social participations; 2.23 (1.57 to 3.16) and 1.47 (1.02 to 2.12) in social relationships and 1.25 (1.08 to 1.45) and 1.29 (1.15 to 1.45) in positive built environments. These associations were also preserved after the restriction of participants who were not in depression. CONCLUSIONS: This study shows that a greater variety of each social relationships and the potential community-level environmental determinants are associated with higher frequencies of laughter in Japan.

Clustering by phenotype and genome-wide association study in autism.

Autism spectrum disorder (ASD) has phenotypically and genetically heterogeneous characteristics. A simulation study demonstrated that attempts to categorize patients with a complex disease into more homogeneous subgroups could have more power to elucidate hidden heritability. We conducted cluster analyses using the k-means algorithm with a cluster number of 15 based on phenotypic variables from the Simons Simplex Collection (SSC). As a preliminary study, we conducted a conventional genome-wide association study (GWAS) with a data set of 597 ASD cases and 370 controls. In the second step, we divided cases based on the clustering results and conducted GWAS in each of the subgroups vs controls (cluster-based GWAS). We also conducted cluster-based GWAS on another SSC data set of 712 probands and 354 controls in the replication stage. In the preliminary study, which was conducted in conventional GWAS design, we observed no significant associations. In the second step of cluster-based GWASs, we identified 65 chromosomal loci, which included 30 intragenic loci located in 21 genes and 35 intergenic loci that satisfied the threshold of P < 5.0 × 10-8. Some of these loci were located within or near previously reported candidate genes for ASD: CDH5, CNTN5, CNTNAP5, DNAH17, DPP10, DSCAM, FOXK1, GABBR2, GRIN2A5, ITPR1, NTM, SDK1, SNCA, and SRRM4. Of these 65 significant chromosomal loci, rs11064685 located within the SRRM4 gene had a significantly different distribution in the cases vs controls in the replication cohort. These findings suggest that clustering may successfully identify subgroups with relatively homogeneous disease etiologies. Further cluster validation and replication studies are warranted in larger cohorts.

Low birth weight and abnormal pre-pregnancy body mass index were at higher risk for hypertensive disorders of pregnancy.

Low birth weight is known to be associated with hypertension, cardiovascular disease and hypertensive disorders of pregnancy (HDP); however, this association might vary by race/ethnicity. This study aimed to clarify the association between women's own birth weight and their subsequent risk for HDP in a Japanese population, in combination with pre-pregnancy body mass index (BMI). We conducted a cohort study as part of the Tohoku Medical Megabank Birth and Three-Generation Cohort Study in Miyagi, Japan. Our study's population included 4810 women. A multivariate logistic regression analysis was performed to calculate the adjusted odds ratio (aOR) and the 95% confidence interval (CI) of the women's own birth weight for HDP, in the combination categories of birth weight and pre-pregnancy BMI. As a result, the group with a low birth weight of <2500 g had a significant association with HDP (the aOR, 1.50; 95% CI, 1.02-2.21). In the subtype analysis, the odds ratio for only preeclampsia was significantly increased in the low birth weight group (aOR, 3.37; 95% CI, 1.84-6.16). In the group with a low birth weight, the prevalence of HDP was higher in both the underweight and overweight groups. In conclusion, there was a significant association between low birth weight and subsequent HDP in Japanese women. Furthermore, a significant association with HDP was found for women born with a low birth weight who were underweight or overweight as adults. Maintaining a normal weight may be effective for preventing HDP even if a woman was born small.

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.

Effectiveness of seasonal inactivated influenza vaccination in Japanese schoolchildren: an epidemiologic study at the community level.

Influenza vaccination is the most effective method for preventing influenza virus infection. The incidence of influenza is higher in schoolchildren than other age groups. This study evaluated the effectiveness of seasonal inactivated influenza vaccination (IIV) in a community population of schoolchildren during two seasons. This study was a cross-sectional survey of public schoolchildren based on data collected in the 2012/2013 and 2014/2015 seasons. The questionnaire was distributed to all public schoolchildren of target grade in a survey area, and 7945 respondents were included in the analysis. The vaccination status and influenza onset were defined based on the self-reported questionnaire by parents or guardians. Generalized linear mixed models were used to adjust clustering within schools and individual covariates and calculate odds ratios (ORs) and 95% confidence intervals (CIs) for associations between vaccination status and influenza onset. The influenza incidence was higher in the 2015 than the 2013 survey (25% versus 17%), although the vaccination rates were comparable between the two seasons. Receiving one- or two-dose vaccination was more protective against influenza than non-vaccination in both the 2013 (OR, 0.77; 95%CI, 0.65-0.92) and 2015 (OR, 0.88; 95%CI, 0.75-1.02) surveys. Full vaccination was also more protective in both the 2013 (OR, 0.75; 95%CI, 0.62-0.89) and 2015 (OR, 0.86; 95%CI, 0.74-1.00) surveys. Seasonal IIV was protective against influenza for Japanese schoolchildren in a community-based real-world setting. The difference in clinical effectiveness of IIV between the two seasons was likely due to the antigenic mismatch between the circulating and vaccine strains.

Potential identification of vitamin B6 responsiveness in autism spectrum disorder utilizing phenotype variables and machine learning methods.

We investigated whether machine learning methods could potentially identify a subgroup of persons with autism spectrum disorder (ASD) who show vitamin B6 responsiveness by selected phenotype variables. We analyzed the existing data from our intervention study with 17 persons. First, we focused on signs and biomarkers that have been identified as candidates for vitamin B6 responsiveness indicators. Second, we conducted hypothesis testing among these selected variables and their combinations. Finally, we further investigated the results by conducting cluster analyses with two different algorithms, affinity propagation and k-medoids. Statistically significant variables for vitamin B6 responsiveness, including combination of hypersensitivity to sound and clumsiness, and plasma glutamine level, were included. As an a priori variable, the Pervasive Developmental Disorders Autism Society Japan Rating Scale (PARS) scores was also included. The affinity propagation analysis showed good classification of three potential vitamin B6-responsive persons with ASD. The k-medoids analysis also showed good classification. To our knowledge, this is the first study to attempt to identify subgroup of persons with ASD who show specific treatment responsiveness using selected phenotype variables. We applied machine learning methods to further investigate these variables' ability to identify this subgroup of ASD, even when only a small sample size was available.

Pooled Analysis of the Associations between Body Mass Index, Total Cholesterol, and Liver Cancer-related Mortality in Japan

Objective: We employed a large-scale pooled analysis to investigate the association of liver cancer-related mortality with being overweight/obese and total cholesterol (TC) levels, since limited and inconsistent data on these associations exist in Japan. Methods: A total of 59,332 participants (23,853 men and 35,479 women) from 12 cohorts without a history of cancer who were followed for a median of 14.3 years were analyzed. A sex-specific stratified Cox proportional hazards model adjusted for age and other potential confounders was used to calculate hazard ratios (HRs) and 95% confidence intervals (CI) for liver cancer-related mortality. Results: A total of 447 participants (266 men and 181 women) died of liver cancer within the follow-up period. Individuals classified as having a high BMI (≥25.0 kg/m2) and low TC levels (<160 mg/dL) had a significantly increased risk for liver cancer-related mortality (HR 7.05, 95% CI 4.41­11.26 in men; HR 8.07, 95% CI 4.76­13.67 in women) when compared with those in the intermediate BMI (18.5­24.9 kg/m2) and TC (160­219 mg/dL) categories. These associations remained after limiting the follow-up duration to >5 years. Conclusion: Being overweight/obese, combined with low TC levels, was strongly associated with liver cancer-related mortality in the EPOCH-JAPAN.

Associations of disaster-related and psychosocial factors with changes in smoking status after a disaster: a cross-sectional survey after the Great East Japan Earthquake.

OBJECTIVE: Few studies have comprehensively examined changes in smoking status and related factors after a disaster. We examined these factors among residents of an evacuation area in Fukushima after the Great East Japan Earthquake. METHODS: The study participants included 58 755 men and women aged ≥20 years who participated in the Fukushima Health Management Survey in 2012 after the disaster. Smoking status was classified as either current smokers or current non-smokers before and after the disaster. The participants were divided into the following groups: (1) non-smokers both before and after the disaster, (2) non-smokers before and smokers after the disaster, (3) smokers before and non-smokers after the disaster and (4) smokers both before and after the disaster. The adjusted prevalence ratios and 95% CIs of changes in smoking status for demographic, disaster-related and psychosocial factors were tested using logistic regression analysis that was stratified by smoking status before the disaster. RESULTS: Among the 44 729 participants, who were non-smokers before the disaster, 634 (1.4%) began smoking after the disaster. Among the 14 025 smokers before the disaster, 1564 (11.1%) quit smoking after the disaster, and the proportion of smokers in the evacuation area consequently decreased from 21.2% to 19.6%. In the multivariable model, factors significantly associated with beginning smoking included being a male, being younger, having a lower education, staying in a rental house/apartment, house being damaged, having experienced a tsunami, change jobs and the presence of traumatic symptoms and non-specific psychological distress. On the contrary, factors associated with quitting smoking included being a female, being older, having a higher education and having a stable income. CONCLUSION: The proportion of smokers slightly decreased among residents in the evacuation area. The changes in smoking statuses were associated with disaster-associated psychosocial factors, particularly changes in living conditions, having experienced a tsunami, change jobs and developing post-traumatic stress disorder.

Impact of social relationships on income-laughter relationships among older people: the JAGES cross-sectional study.

OBJECTIVES: Laughter has a positive and quantifiable effect on certain aspects of health, and previous studies have suggested that income influences the emotion. However, it is unknown whether social relationship-related factors modify the association between equivalised income and laughter among older people. In the present study, we examined the relationship between equivalised income and the frequency of laughter. In addition, we examined the impact of social relationship-related factors on the association between equivalised income and frequency of laughter using a cross-sectional study design. DESIGN: Cross-sectional study and binomial regression analysis. SETTING: We sampled from 30 municipalities in Japan. PARTICIPANTS: We examined 20 752 non-disabled Japanese individuals aged ≥65 years using data from the Japan Gerontological Evaluation Study. PRIMARY OUTCOME: Frequency of laughter. RESULTS: Laughter increased significantly with an increase in equivalent income (p for trend <0.0001). Prevalence ratios (PR) for laughing almost every day were calculated according to quartile equivalised income after adjusting for age, instrumental activities of daily living, depression, frequency of meeting friends, number of social groups and family structure. The results revealed that PRs in Q4 (men; ≥€24 420, women; ≥€21 154) were 1.21 (95% CI 1.13 to 1.30) among men and 1.14 (95% CI 1.08 to 1.20) among women, as compared with Q1 (men; <€12 041, women; <€9518), respectively. After excluding participants with depression, the association remained significant. In addition, we found inadequate social relationships and living alone were associated with a lower frequency of laughter. In comparison with the lowest equivalent income with meeting friends less frequently and living alone, the PRs of the highest equivalent income with meeting friends frequently and living with someone were higher, respectively. CONCLUSIONS: The results revealed a significant relationship between equivalent income and the frequency of laughter. Social relationships and family structure were also associated with the frequency of laughter.

Relationships among personality traits, metabolic syndrome, and metabolic syndrome scores: The Kakegawa cohort study.

OBJECTIVE: Metabolic syndrome and the presence of metabolic syndrome components are risk factors for cardiovascular disease (CVD). However, the association between personality traits and metabolic syndrome remains controversial, and few studies have been conducted in East Asian populations. METHODS: We measured personality traits using the Japanese version of the Eysenck Personality Questionnaire (Revised Short Form) and five metabolic syndrome components-elevated waist circumference, elevated triglycerides, reduced high-density lipoprotein cholesterol, elevated blood pressure, and elevated fasting glucose-in 1322 participants aged 51.1±12.7years old from Kakegawa city, Japan. Metabolic syndrome score (MS score) was defined as the number of metabolic syndrome components present, and metabolic syndrome as having the MS score of 3 or higher. We performed multiple logistic regression analyses to examine the relationship between personality traits and metabolic syndrome components and multiple regression analyses to examine the relationship between personality traits and MS scores adjusted for age, sex, education, income, smoking status, alcohol use, and family history of CVD and diabetes mellitus. We also examine the relationship between personality traits and metabolic syndrome presence by multiple logistic regression analyses. RESULTS: "Extraversion" scores were higher in those with metabolic syndrome components (elevated waist circumference: P=0.001; elevated triglycerides: P=0.01; elevated blood pressure: P=0.004; elevated fasting glucose: P=0.002). "Extraversion" was associated with the MS score (coefficient=0.12, P=0.0003). No personality trait was significantly associated with the presence of metabolic syndrome. CONCLUSIONS: Higher "extraversion" scores were related to higher MS scores, but no personality trait was significantly associated with the presence of metabolic syndrome.

The Relationship between Sleep Time and Mental Health Problems According to the Strengths and Difficulties Questionnaire in Children after an Earthquake Disaster: The Fukushima Health Management Survey.

A cross-sectional study was performed on the adverse effects of sleep time on the mental health of children after the Great East Japan Earthquake and subsequent nuclear reactor accident in March 2011. The target participants were children aged 4-15 years living inside the government-designated evacuation zone as of 11 March 2011 (n = 29,585). The participants' parents/guardians completed the Strengths and Difficulties Questionnaire (SDQ) and sleep time data were obtained from the 2011 Fukushima Health Management Survey. A total of 18,745 valid responses were returned. We excluded questionnaires with incomplete answers leaving 13,272 responses for the final analysis. First, we divided the children into three age groups for analysis. Second, we divided each age group into four or five groups based on sleep time per day. We used SDQ scores ≥16 to indicate a high risk of mental health problems. In the 4-6-year-old group, those with a sleep time of <9 h had a higher risk. In the 7-12-year-old group, those with ≥10 h of sleep time had a higher risk. In the 13-15-year-old group, those with ≥9 h of sleep time had a higher risk. Shorter sleep time was associated with a higher risk of mental health in 4-6-year-olds. On the other hand, oversleeping was associated with a high risk of mental health in 7-15-year-olds.

Impact of evacuation on trends in the prevalence, treatment, and control of hypertension before and after a disaster.

OBJECTIVE: After the Great East Japan Earthquake in 2011, the prevalence of cardiovascular disease risk factors increased in victims. We examined the trends in the prevalence, treatment, and control of hypertension before and after the disaster, as well as the impact of evacuation. METHODS: Study participants were approximately 10 000 men and 12 000 women aged 40-74 years in each year from 2008 to 2014. All of the participants had lived in radiation evacuation zones prior to the Fukushima nuclear crisis. The age-standardized prevalence, treatment, and control of hypertension were calculated using the direct method. In a comparison of evacuees with nonevacuees, the proportion ratios and 95% confidence intervals for hypertension, treatment, and control were calculated by Poisson regression with robust error variance adjusted for covariates in each year after the disaster. RESULTS: The age-standardized prevalence of hypertension peaked in 2012 at 48.8% in men and 39.0% in women. By 2014, the treatment and control of hypertension had increased to 66.3 and 67.1% in men, and 70.6 and 68.1% in women, respectively. The multiadjusted proportion ratios for the prevalence, treatment, and control of hypertension in any given year were 1.02-1.03, 0.99-1.05, and 0.93-1.06 in men, and 0.96-1.00, 0.99-1.05, and 1.06-1.11 in women, respectively. CONCLUSION: The prevalence of hypertension peaked 1 year after the disaster, while the treatment and control of hypertension increased thereafter. These results indicate that evacuation had little to no impact on the prevalence, treatment, and control of hypertension in the population of Fukushima Prefecture.

Perception of Radiation Risk as a Predictor of Mid-Term Mental Health after a Nuclear Disaster: The Fukushima Health Management Survey.

Predictive factors including risk perception for mid-term mental health after a nuclear disaster remain unknown. The purpose of this study was to examine the association between perceived radiation risk and other factors at baseline and mid-term mental health after the Fukushima Daiichi nuclear disaster of 2011 in Japan. A mail-based questionnaire survey was conducted in January 2012 and January 2013. Mental health status was assessed using the K6 scale. Psychological distress over the 2-year period was categorized into the following four groups: chronic, recovered, resistant, or worsened. Most participants (80.3%) were resistant to the disaster. A positive association was found between the radiation risk perception regarding immediate effects and the worsened group in women. Baseline post-traumatic stress disorder (PTSD) or a history of psychiatric disease predicted being in the chronic or worsened group in mid-term course. These results suggest that evacuees who believed that their health was substantially affected by the nuclear disaster were at an increased risk of having poor mid-term mental health in women. Careful assessment of risk perception after a nuclear disaster, including the presence of PTSD or a history of psychiatric disease, is needed for appropriate interventions.

Effects of socioeconomic factors on cardiovascular-related symptoms among residents in Fukushima after the Great East Japan Earthquake: a cross-sectional study using data from the Fukushima Health Management Survey.

OBJECTIVE: To investigate the association between socioeconomic factors and the exacerbation of cardiovascular symptoms among evacuees after the Great East Japan Earthquake. METHODS: A sample of 73 433 individuals was included in the Fukushima Health Management Survey. Self-report questionnaires were used to determine the influence of socioeconomic factors including living arrangements, loss of employment and decreased income on the exacerbation of headache, dizziness, palpitations and shortness of breath. Odds ratios (ORs) and 95% CIs of the effect of socioeconomic factors were estimated for each symptom using multiple logistic regression analyses. RESULTS: Exacerbation of headaches was reported by 1893 individuals, dizziness by 1229, palpitations by 1085 and shortness of breath by 626 individuals. Evacuation accommodation was associated with all of these symptoms. Compared with participants living in their own home (OR=1.00), individuals living in relatives' homes had increased probability of experiencing exacerbation of headache (1.58; 95% CI 1.19 to 2.09) and dizziness (1.42; 95% CI 1.02 to 1.98); those living in rental housing or apartments experienced exacerbation of headache (1.54; 95% CI 1.32 to 1.80), dizziness (1.45; 95% CI 1.20 to 1.75), palpitations (1.25; 95% CI 1.03 to 1.51) and shortness of breath (1.76; 95% CI 1.35 to 2.28); participants living in evacuation shelters experienced exacerbation of headache (1.80; 95% CI 1.09 to 2.96); and refugees living in temporary housing also experienced exacerbation of headache (1.42; 95% CI 1.15 to 1.72), dizziness (1.40; 95% CI 1.09 to 1.79) and shortness of breath (1.49; 95% CI 1.07 to 2.08). Compared with the evacuees who retained their jobs, unemployed individuals showed increased probability of exacerbation of headache (1.28, 95% CI 1.12 to 1.46), dizziness (1.26, 95% CI 1.07 to 1.48) and palpitations (1.21, 95% CI 1.01 to 1.45). Decreased income was associated with exacerbation of headache (1.39, 95% CI 1.22 to 1.60). CONCLUSION: After the earthquake, living in non-home conditions was more likely to result in exacerbated cardiovascular symptoms among evacuees. Loss of employment was another risk factor related to exacerbated headache and dizziness.