Abstract
Suicides in Japan consistently decreased from 2009-2019, but increased during the COVID-19 pandemic. To identify causes of increasing suicides, age-dependent and temporal fluctuations of suicide mortality rate per 100,000 (SMRP) in working-age generations (20-59 years) disaggregated by suicidal motives (7-categories; 52-subcategories) and sex from 2007 to 2022, were analyzed by analysis of variance and joinpoint regression, respectively, using the government suicide database "Suicide Statistics". The SMRP of 20-29 year-old males and 20-49 year-old females began to increase in the late 2010s. SMRPs of these high-risk groups for suicides caused by depression (the leading suicidal motive for all groups) began increasing in the late 2010s. Economic-related, employment-related, and romance-related problems contributed to the increasing SMRPs in 20-29 males in the late 2010s. Romance-related and family-related problems contributed to the increasing SMRPs of 20-29 females in the late 2010s. Increasing SMRPs caused by child-raising stress in 20-39 year-old females from the late 2010s was a remarkable finding. In contrast, SMRPs of 30-59 year-old males consistently decreased until 2021; however, in these groups, SMRPs for suicides caused by various motives sharply increased in 2022. The consistent increase in SMRPs of high-risk groups from the late 2010s to the pandemic suggest recent socioeconomic and psychosocial problems in Japan possibly contributed to the increasing SMRPs in these high-risk groups independently of pandemic-associated factors, whereas the SMRPs of males of 30-59 years were probably associated with the ending of the pandemic rather than pandemic-associated factors.