The Age-Period-Cohort trends of suicide in Hong Kong and Taiwan, 1979-2018

Background: The global age-standardized suicide rate fell by 32.7% between 1990 and 2016. The decrease was largely due to suicide rate reductions in China and India. High-income Asian regions did not see such reductions. The aim of the current study was to explore recent suicide rate trends in Hong Kong and Taiwan to decompose which factors - age, period or cohort - explain suicide rate changes in these two regions. Methods: Official mortality data for 1979-2018 in Hong Kong and Taiwan were collected. We utilized Web Tool from the NIH (National Institute of Health, USA) to analyze the Age-Period-Cohort (APC) effects. Results: We found marked age-effect that suicide rates increased with age in both genders in both places. Period effect related to the dissemination of charcoal burning suicide was found during 1999-2003 in Hong Kong and 2004-2008 in Taiwan. Increasing suicide rates in the middle- and young-age male cohorts were found in both regions. No increase in suicide risks in young female cohorts was observed. Older cohorts in Hong Kong and older female cohorts in Taiwan also had high suicide rates, but older male cohorts in Taiwan had low rate. Limitations: The interpretations and observations at the population level might not hold at the individual level. Conclusions: The high suicide risk in middle- and young male cohorts in both regions contribute to the persistent high suicide rates in these two regions. Special attention should be turn to the factors underlying such increasing trends.