Aim: Prolonged periods of instability in terms of living environment can lead to a serious increase in mental health issues among disaster‐affected individuals. The aim of this study was to assess long‐term trends in mental health among adult residents in a nuclear‐disaster‐affected area.Methods: Mail‐based, self‐administered questionnaire surveys were conducted three times (T1–T3), targeting all residents registered with the municipalities in the evacuation zone in Fukushima prefecture at the time of the disaster. Age‐adjusted prevalences of the following were analyzed by sex: risk of psychological distress by the Kessler 6‐item Scale, post‐traumatic stress by the Post‐traumatic Stress Disorder Checklist, and problem drinking by CAGE.Results: The numbers of respondents and response rates were: 73 568, 40.7% (T1); 55 076, 29.9% (T2); and 46 386, 25.0% (T3). Compared with normal Japanese levels in non‐disaster settings (4.7%), the prevalence of general psychological distress by Kessler 6‐item Scale ≥ 13 was still high 3 years after the event in both men (11.4%) and women (15.8%). Although the age‐adjusted prevalence of psychological distress and post‐traumatic stress (Post‐traumatic Stress Disorder Checklist ≥ 44) had decreased over time (from 19.0% [T1] to 17.8% [T3] for men, and from 25.3% [T1] to 23.3% [T3] for women), the age‐adjusted prevalence of problem drinking (CAGE ≥ 2) remained steady in both men (20.7% [T2] and 20.4% [T3]; P = 0.18) and women (10.5% [T2] and 10.5% [T3]; P = 0.91).Conclusion: Our results suggest that long‐term interventions focused on post‐traumatic stress as well as other mental health problems are strongly needed for disaster‐affected individuals.

Few studies have investigated the relationship between living arrangements and dietary intake among evacuees after disasters. To examine the relationship between living arrangements and dietary intake using the data of a large-scale cohort survey of evacuees after the Great East Japan Earthquake in 2011. 73,433 residents in evacuation zones responded to the Fukushima Health Management Survey questionnaire. Subjects were excluded if they did not report their living conditions or were missing more than three pieces of information about dietary intake. The data of 52,314 subjects (23,149 men and 29,165 women ≥15 years old) were used for the analyses. Evacuees' living arrangements were characterized into three categories: evacuation shelters or temporary housing, rental houses or apartments, or a relative's home or their own home. Dietary intake was characterized in terms of grains, fruits and vegetables, meat, soybean products, dairy products, and fish. Daily consumption of the third quartile (Q3) or higher for each food group was defined as 'high consumption'. Prevalence ratios (PRs) and 95% confidence intervals (CIs) were estimated using modified Poisson regression analyses. Modified Poisson regression analyses showed that, compared with respondents living in a relative's home or their own home, the PRs and 95% CIs for the people living in rental apartments of high consumption of fruits and vegetables (non-juice), meat, soybean products, and dairy products were 0.69 (95% CI, 0.61-0.77), 0.82 (95% CI, 0.73-0.91), 0.89 (95% CI, 0.83-0.94), and 0.83 (95% CI, 0.74-0.93) respectively. The corresponding PRs and 95% CIs for people living in evacuation shelters or temporary housing were 0.83 (95% CI, 0.78-0.88), 0.90 (95% CI, 0.86-0.95), 0.94 (95% CI, 0.91-0.97), and 0.91 (95% CI, 0.86-0.96) for high consumption of fruits and vegetables (non-juice), meat, soybean products, and dairy products, respectively. The present study suggests that, after the earthquake, living in non-home conditions was associated with poor dietary intake of fruits and vegetables (non-juice), meat, soybean products, and dairy products, suggesting the need for early improvements in the provision of balanced meals among evacuees living in non-home conditions.

Objectives The Fukushima Daiichi Nuclear Power Plant accident, which occurred after the Great East Japan Earthquake and Tsunami in March 2011, may have a considerable long-term impact on the lives of area residents. The aims of this study were to determine the trajectories of psychological distress using 3-year consecutive data, and to find predictive factors of severe distress that may also prove useful for public health intervention. Methods Data were obtained on 12 371 residents who were registered in the municipalities categorised as complete evacuation areas for 3 years after the disaster and who completed an assessment in each of the 3 years. Results Using group-based trajectory modelling, we identified four trajectory patterns distinguished by the levels of psychological distress, which gradually improved over time in all trajectories. Subjective sleep insufficiency, problem drinking, poor social support and perception of radiation risk 3 years after the accident were associated with the severity of psychological distress, according to the multivariate analysis. Conclusions The identified factors may be useful for community-based mental healthcare over the long term following a nuclear disaster.

Objective Psychological distress is generally associated with poor dietary intake, but this has never been investigated among residents after a major disaster. We attempted to reveal the associations between dietary intake and non-specific mental health distress as well as traumatic symptoms among evacuees after the Great East Japan Earthquake of 2011. Methods In this cross-sectional analysis of 63 047 evacuees (27 901 men, 35 146 women) who responded to The Fukushima Health Management Survey in 2012, non-specific mental health distress was assessed using the Kessler-6 (K6) scale, while traumatic symptoms were evaluated using the Post-traumatic Stress Disorder (PTSD) Checklist—Stressor-Specific Version (PCL-S). The outcome was ‘low frequency’—meaning a daily consumption in the 25th centile or less according to the food frequency questionnaire (FFQ)—of 19 targeted food items. Logistic regression analysis was used to estimate ORs and 95% CIs adjusted for demographic, lifestyle-related and disaster-related factors. Results Of the participants, 14.7% suffered non-specific mental health distress, and 21.2% exhibited traumatic symptoms. Multivariable adjusted logistic regression analysis showed that the former were likely to have a low intake frequency of certain foods, such as rice and bread, fish, meat, vegetables or fruit (non-juice), soya bean products, milk, and yogurt or lactobacillus drinks; the latter were also likely to have a low intake frequency of certain foods, including rice and bread, fish, meat, vegetables (non-juice), milk and yogurt or lactobacillus drinks, but conversely consumed vegetable and fruit juices more often. These associations between dietary intake and non-specific mental health distress, as well as traumatic symptoms, were predominantly observed in women. Conclusions Psychological distress after the Great East Japan Earthquake among evacuees was associated with a low intake frequency of certain foods, and the association was predominantly observed in women.

After the Fukushima nuclear power plant accident, numerous evacuees reported poor mental health status and high-risk perceptions of the health effects of radiation. However, the temporal associations between these variables have not yet been examined. Using data from the Fukushima Health Survey, we examined changes in risk perception of the health effects of radiation over time and assessed the effects of mental health on such changes using logistic regression analysis. Risk perception for delayed effect pertains a brief on health effect in later life (delayed effect), whereas that of genetic effect pertains a brief on health effect of future children and grandchildren (genetic effect). We found that many participants showed consistently high or low-risk perceptions over all three study years (2011–2013) (for delayed effect: 59% and 41% of participants were in the low and high-risk perception groups, respectively; for genetic effect: 47% and 53%, respectively). Stronger traumatic reactions (≥50 on the PTSD Checklist–Specific) significantly affected the odds of being in the high-risk perception group for the delayed and genetic effects, with the associations being strongest soon after the disaster: The adjusted ORs (95%CIs) were 2.05 (1.82–2.31), 1.86 (1.61–2.15), and 1.88 (1.62–2.17) for the delayed effect in 2011, 2012, and 2013, respectively, and 2.18 (1.92–2.48), 2.05 (1.75–2.40), and 1.82 (1.55–2.15) for the genetic effect. As initial mental health status had the strongest impact on later risk perceptions of radiation, it should be considered in early response and communication efforts.

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.