The suicide epidemic in Japan and strategies of depression screening for its prevention

Abstract

Introduction Suicide is among the most tragic outcomes of all mental disorders. WHO estimates that, worldwide, there are approximately one million deaths from suicide each year, and 20 times this number of people attempt suicide. Although the Japanese population leads the world in longevity, it has a high rate of suicide that is globally ranked ninth. From 1995 to 2004, the incidence of reported suicides rose dramatically from 17.5 to 25.1 per 100 000. Some studies have reported that this increase is closely related to the economic depression that occurred in Japan over the same period. While a reduction in suicide rates may depend on an economic recovery, public health practitioners must try to help potentially suicidal individuals, regardless of outside influences such as the economy. Depression plays an important role in the etiology of suicide. Over 60% of the individuals who commit suicide were identified as depressive. Reducing the number of suicide attempts requires, therefore, an initial identification of people with potential depression. When the University of Iowa's psychiatric department hosted clinics on the National Depression Screening Day in the USA in 1996, 65% of the 927 participants required further evaluation, of whom 83% subsequently received treatment for depression. (1) Efforts made in the USA indicate that tactics instituted to identify depression can work well to reduce suicide rates at the national level. In 2000, the Japanese Government declared its goal to reduce the annual incidence of suicide by 30% until 2010. The National Committee published proposals for suicide prevention in 2002, emphasizing the importance of pre-intervention (assessment of factors affecting suicide), intervention (identification of high-risk persons to prevent suicide) and post-intervention (social support for bereaved family and friends). They also published two guidelines for managing depression: one for health-care professionals and one for public servants. The guidelines recommend a screening test for depression in the workplace and the community, using a method based on the full criteria of the Statistical manual of mental disorders, 4th edition, text revision (DSM-IV-TR), including eight or nine items for assessment. A simpler method is required to promote screening for depression nationwide. Fulfilment of the national goal within the next five years will require identification of target groups and extensive intervention for high-risk persons in these groups. Identification of target groups Depression is one of the most rapidly spreading mental disorders in Western countries and in Japan. According to the National Survey in Japan, the number of individuals diagnosed with depression increased from 83.1 to 340.0 per 100 000 during the period 1984-98. Although depression is generally more common in women than in men, the most dramatic increase has involved middle-aged men (40-60 years); this tendency also applies to the percentage of the population who commit suicide. In Japan, most middle-aged men function as the family breadwinner and may be too busy with work to visit a clinic, even when they feel mental distress. Because it is mandatory for all workers in Japan to undergo health check-ups every year at the expense of their employers, targeting middle-aged men in the workplace is a good strategy for identifying potentially depressive persons. Simple screening methods to detect depression The most commonly used standard for the diagnosis of major depressive disorder (MDD) is a structured interview by a specialist, such as a psychiatrist, according to the DSM-IV-TR criteria. Essential MDD symptoms are depressive mood and a loss of interest lasting at least two weeks; diagnosis also requires three additional concurrent symptoms (e.g. appetite loss, fatigue and insomnia). With the possible exceptions of psychiatrists and psychological specialists, diagnosing depression is not an easy task: interviews are somewhat complex and are time consuming. …