Mayumi Harigane

Three-year trend survey of psychological distress, post-traumatic stress, and problem drinking among residents in the evacuation zone after the Fukushima Daiichi Nuclear Power Plant accident [The Fukushima Health Management Survey].

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.

Predictors of severe psychological distress trajectory after nuclear disaster: evidence from the Fukushima Health Management Survey

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.

Drinking Behavior and Mental Illness Among Evacuees in Fukushima Following the Great East Japan Earthquake: The Fukushima Health Management Survey

Background Recent evidence from alcohol and trauma studies suggests that disasters are associated with increases in the consumption of alcohol. The Great East Japan Earthquake and the associated nuclear disaster have continued to affect the mental health of evacuees from Fukushima. This study aimed to extend these findings by examining the relationship between drinking behaviors and the risk of mental illness after the compound disaster. Methods We conducted the Mental Health and Lifestyle Survey with 56,543 evacuees. Kesslers K6 was used to assess the risk of mental illness, and logistic regression models were applied to analyze how drinking behavior patterns influence the risk of serious mental illness after adjustment for confounding variables. Results Logistic regression analysis evidenced that beginning heavy and light drinkers had the highest and a higher risk of serious mental illness, respectively. Individuals who were nondrinkers pre‐ and postdisaster had the lowest proportional risk of mental illness. Abstainers also had some risk to their mental health after the compound disaster. Conclusions The results of this study highlight that beginning drinkers have a high risk of serious mental illness. Thus, mental health professionals should pay attention to the drinking behaviors of evacuees, which might predict increased risk of serious mental illness and consequently indicate a need for psychological intervention.

Changes of Posttraumatic Stress Responses in Evacuated Residents and Their Related Factors: A 3-Year Follow-up Study From the Fukushima Health Management Survey

The longitudinal posttraumatic stress responses and resilient factors after the Fukushima Daiichi Nuclear Power Plant are yet unknown. Here we attempted to quantify the patterns of the course of posttraumatic stress disorder (PTSD) symptoms and we explored the factors associated with psychological recovery. The subjects were 12 371 residents in the municipalities categorized as the forced evacuated area. We categorized the subjects’ PTSD symptoms into 4 groups: Chronic, Resistant, Recovered, and Non-recovered. We applied a logistic regression to clarify the factors related to psychological recovery. We observed that laughter showed significant odds ratio in the Recovered group and the Resistant group. Meanwhile, elderly residents and those with poor living circumstances showed significant odds ratios for the Recovered group and the Resistant group. Laughter in daily life was associated with the psychological health in the evacuation area.

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.

Exercise Habits Are Important for the Mental Health of Children in Fukushima After the Fukushima Daiichi Disaster: The Fukushima Health Management Survey

After the Great East Japan Earthquake and the subsequent nuclear reactor accident, the outdoor activities of children greatly decreased. We investigated adverse effects on the exercise habits and mental health of children after the disaster. The target subjects were children aged 6 to 15 years living inside the government-designated evacuation zone as of March 11, 2011 (n = 29  585). The subjects’ parents/guardians completed the Strengths and Difficulties Questionnaire (SDQ) and exercise habit 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 10  824 responses for the final analysis. SDQ scores ≥16 indicated high risk of mental health. Children in the evacuation zone who did not get regular exercise had a higher risk of mental problems as evaluated by SDQ (multivariate-adjusted prevalence ratio [PR] = 1.49; 95% CI 1.38-1.62). When stratified by sex, age, place of residence, treatment for illnesses and experienced the nuclear reactor accident the associations were essentially the same. Regular exercise is important for maintaining children’s mental health after a disaster. This is the first large-scale report to examine the impact of outdoor exercise limitations among children in a nuclear accident.

Association between psychological distress and dietary intake among evacuees after the Great East Japan Earthquake in a cross-sectional study: the Fukushima Health Management Survey

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.

Psychometric evaluation of the simplified Japanese version of the Athens Insomnia Scale: The Fukushima Health Management Survey

We investigated the psychometric properties of the simplified Japanese version of the Athens Insomnia Scale (AIS‐SJ) using baseline data from the Fukushima Health Management Survey. Data from 22 878 men and 27 669 women aged 16 years and older were analysed (Mage = 52.9 ± 18.6). Participants lived in the Fukushima evacuation zone and experienced the Great East Japan Earthquake. The AIS‐SJ was used to assess participants’ insomnia symptoms, and its validity was examined by administering the Kessler 6‐item Psychological Distress Scale (K6) and assessing education, self‐rated health and disaster‐related experiences. A confirmatory factor analysis revealed that the two‐factor model was a better fit than the one‐factor model. The AIS‐SJ and its subscales had acceptable reliability (Cronbachs alpha, 0.81). Test of measurement invariance confirmed strict invariance across groups for the participants’ characteristics of gender and mental illness history, but not for participants’ age. AIS‐SJ scores exhibited a near‐normal distribution (skewness, 0.45; kurtosis, −0.89). There were significant age differences only among women, and gender differences in AIS‐SJ scores with small effect sizes. The AIS‐SJ scores had weak‐to‐moderate correlations with mental illness history, bereavement, experiencing the tsunami, experiencing the nuclear power plant incident, housing damage and losing ones job (polyserial correlations, 0.36, 0.17, 0.13, 0.18, 0.13, and 0.15, respectively), and strong correlations with self‐rated health (polyserial correlation, 0.51), psychological distress (rs, 0.60) and post‐traumatic stress disorder (rs, 0.60). The AIS‐SJ is a useful instrument for assessing community dwellers’ insomnia symptoms.

Trajectories of Emotional Symptoms and Peer Relationship Problems in Children after Nuclear Disaster: Evidence from the Fukushima Health Management Survey

The Fukushima Daiichi Nuclear Power Plant accident, which occurred in March 2011, is having long-term effects on children. We planned this study to describe the trajectories of emotional symptoms and peer relationship problems in children and to examine potential risks and protective factors over the 35 months following the accident. The sample was 11,791 children in the first to sixth elementary grades. We identified four patterns for emotional symptoms and three patterns for peer relationship problems, using group-based trajectory modelling. For emotional symptoms, female gender, experience of tsunami and nuclear plant accident, out-of-prefecture evacuees, and insufficient physical activity were associated with the very severe trajectory. In contrast, for peer relationship problems, male gender, experience of nuclear plant accident, and insufficient physical activity were associated with the very severe trajectory. Different factors might be related to the very severe trajectories of emotional symptoms and peer relationship problems.

Changes in Risk Perception of the Health Effects of Radiation and Mental Health Status: The Fukushima Health Management Survey

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.