Five-year longitudinal changes in mental health of workers affected by the Kumamoto earthquakes

Abstract

【Purpose】 Japan is a disaster-prone country having experienced the fourth highest annual frequency of earthquakes in the world between 1980 and 2000 according to the United Nations Development Programme. We have been studying the effects of earthquakes on health and factors that affect post-traumatic stress disorder; however, only a few longitudinal studies on earthquakes have been carried out. This study aimed to clarify five-year longitudinal changes in the mental health status of workers affected by the 2016 Kumamoto earthquakes. 【Methods】 The subjects were 111 people who experienced the 2016 Kumamoto earthquake and responded to three of four surveys (at six months, one, three, and five years after the earthquake). The survey items are basic attributes (gender, age, type of work, damage, et al), health-related QOL (Short-Form Health Survey; SF8), mental health questionnaire (General Health Questionnaire; GHQ28). It consisted of the Impact of Event Scale-Revised (IES-R). 【Results】 There were 104 subjects (84 males and 20 females) who responded at five years after the earthquakes, with a mean age of 49.8 years (SD 13.3). The mental health status of workers at five years after the Kumamoto earthquakes showed deterioration in the GHQ28 total score and subscale for somatic symptoms. At three years after the earthquakes, there was deterioration in depressive tendencies, AIS scores, and the subjective sense of health. 【Conclusion】 The results of the five-year survey study revealed that mental health was particularly affected three years after the earthquake. A possible explanation for this phenomenon is given in the lack of prospects for housing reconstruction, isolation due to changes in the living environment and relationships with neighbors due to moving, and other factors. Screening should be conducted as early as possible after a disaster and a continuous support system should be put in place to provide proactive mental health care by the government and other corporate managers, replacing the need to rely on complaints among individuals.