Sleep Disturbance of Evacuees in Minamisanriku Town after Great East Japan Earthquake: Risk Factors and Treatment

Abstract

In 2011, Minamisanriku Town lost all of its medical facilities during the Great East Japan Earthquake. Using 10,459 anonymized disaster medical records of affected people in Minamisanriku Town, we assessed the prevalence and risk factors of sleep disturbance, which is known to exacerbate non-communicable diseases (NCDs) and anxiety disorder. Because sleep disturbance is a part of mental health issues, we divided the patients into two groups: patients (n = 492) with mental health issues other than sleep disturbance and the remaining (n = 9,967) with other comorbidities. Out of 492 patients with mental health issues, 295 patients (60.0%, 114 male, 158 female and 23 unknown) had sleep disturbance who might have required specific treatments. Out of the remaining 9,967 patients, 1,203 patients (12.1%, 361 male and 769 female and 73 unknown) had sleep disturbance. Univariate and multivariate analyses of the 9,967 patients revealed that the odds ratio (OR) of sleep disturbance was higher for female (OR 1.95), elderly persons over 60 (OR 16.15) and residing in evacuation centers (OR 1.36). Patients with two or more NCD had higher risk (OR 1.42). Importantly, sleep disturbance affects younger patients without NCD residing in evacuation center. Emergency medical teams most frequently prescribed benzodiazepines both for sleep induction and anxiolysis. In addition to high risk groups (female, older, with other mental health issues, residing in evacuation center), it is important to survey sleep disturbance in younger and healthier populations especially in evacuation centers and to provide psychosocial and medical support for them.

Sleep Problems among Disaster Victims: A Long-Term Survey on the Life Changes of Disaster Victims in Korea

“…A binary logistic regression analysis showed that marital status, household type, disaster type, time elapsed after a disaster, subjective health status, depression, and PTSD affect the sleep quality of disaster victims. In a previous study, women and older people were reported to be mentally vulnerable to disaster-like situations [25], and Onose et al [43] reported that women were more susceptible to PTSD. In our study, PTSD was a significant variable affecting sleep quality; however, gender was, surprisingly, not a significant variable in the regression analysis.…”

“…One of the main factors associated with stress vulnerability is biological sex [44], and stress is associated with the incidence and severity of several psychiatric disorders, including PTSD and depression, that occur more often in women than in men [44]. Therefore, a sex-based approach to sleep disturbance and mental health management to resolve sleep disturbance would be important in reducing the PTSD resulting from disasters [25].…”

“…Therefore, it is necessary to consider the characteristics of disaster victims, including their socio-cultural differences and their experiences before and after the disaster, to understand the victims' health problems [24]. In addition, recent research reports that studies on sleep disturbance in not only high-risk groups (women, the elderly, and those with other mental health problems) but also in young and healthy adults are necessary to establish psychosocial and medical support for this demographic [25].…”

Progress of Disaster Medicine during Ten Years after the 2011 Great East Japan Earthquake

“…Noncommunicable disease (NCD) (68%) was the most frequent medical needs, followed by, infectious disease (21%), mental health issues (6%), trauma (4%), and mother and child health issues (0.2%). Using the same database, Nakamura et al (2020) revealed that evacuees had high prevalence of sleep disturbance. Aged population and female gender were the risk factors, but sleep disturbance rather affected younger evacuees regardless of gender who does not have NCD but residing in evacuation center, stressing the importance of awareness of sleep disturbance in such populations especially in evacuation centers.…”

Epidemiology of Sleep Disturbances and Their Effect on Psychological Distress During the COVID-19 Outbreak: A Large National Study in China

“…Females are twice as likely to suffer from sleep disruptions as males (Mong et al, 2011 ). During a previous earthquake crisis, sleep disturbances were more prevalent among females than males (Nakamura et al, 2020 ). In addition, gender differences have been reported in the experience of mental health issues.…”