The course of chronic and delayed onset of mental illness and the risk for suicidal ideation after the Great East Japan Earthquake of 2011: A community-based longitudinal study.

This study investigated how the course of a mental illness is distributed and evaluated the risk factors and suicidality of chronic and delayed onset mental illness after the Great East Japan Earthquake. The first, second, and third waves of this study were conducted in 2012, 2013, and 2014, respectively. Psychological distress, suicidal ideation, and socio-demographics were assessed by a self-report questionnaire for affected residents (N = 1473; 768 females, 52.1%; average age = 66.3 years, ranged from 20 to 89 years). Prevalence of mental illness was 10.0%, 14.7%, and 11.8% in the first, second, and third waves, respectively. Prevalence of mental illness for three years was found to be 21.4% and of remission, chronic, and delayed-onset course was 5.0% (2.9-7.1%), 3.6% (1.6-5.8%), and 6.2% (4.2-8.4%), respectively. Psychological distress and serious damage to their homes in the first wave predicted chronic course. Psychological distress in the first wave, living at temporary housing, and unemployment in the third wave increased risk for delayed onset. Among the participants, 9.8% reported suicidal ideation. Chronic or delayed onset course showed a higher risk of suicidal ideation. Many residents, who showed high risk of suicidality, still suffer from mental illness requiring housing, occupation, and psychological support.