Predictors of Depressive Symptoms Following the Great East Japan Earthquake: A Prospective Study

We sought to investigate prospectively the association between exposure to disaster (the 2011 East Japan Earthquake) and change in depressive symptoms among community-dwelling older adult survivors. We used two waves of data from the Japan Gerontological Evaluation Study (JAGES), an ongoing population-based, prospective cohort study in Japan. A unique feature of our study was the availability of information about mental health status pre-dating the disaster. Our sample comprised community-dwelling survivors aged 65 and older, who responded to surveys in 2010 (i.e. one year before the disaster) and in 2013 (n = 3464). We categorized disaster exposure according to three types of experiences: loss of family/friends, property damage, and disruption in access to medical service. Our main outcome was change in depressive symptoms, measured by the 15-item geriatric depression scale (GDS). Among the participants, 917 (26.5%) reported losing a family member to the disaster, while a further 537 (15.5%) reported losing a friend. More than half of the participants reported some damage to their homes. After adjusting for demographics and baseline mental health, people whose homes were completely destroyed had significantly elevated depressive symptom scores three years later (+1.22 points, 95%CI: 0.80, 1.64, p < 0.0001). Disruption of psychiatric care was also associated with change in GDS scores (+2.51 points, 95%CI: 1.28, 3.74, p < 0.0001). By contrast, loss of family/friends was no longer associated with GDS after 3 years; +0.18 points (95%CI: -0.018, 0.37, p = 0.08) for loss of family, and -0.045 points (95%CI: -0.28, 0.19, p = 0.71) for loss of friends. Three years after the disaster, survivors of the 2011 earthquake and tsunami appeared to have recovered from loss of loved ones. By contrast, property loss and disruption of psychiatry care were associated with persistent adverse impact on mental health.