Exploring possible causes of lower-than-expected suicide rates in Taiwan and South Korea during the 2020–2021 COVID-19 pandemic: a time trend analysis by sex, age, and method

Aims: Decreases in suicide rates during the coronavirus disease 2019 (COVID-19) pandemic were found in several countries, including Taiwan and South Korea. We investigated the pattern of the reduction in suicide by sex, age, method, and outbreak period in the two countries. Methods: Suicide data for Taiwan (2015–2021) and South Korea (2017–2021) stratified by sex, age, method, and month were extracted from national mortality data files in the two countries. Negative binomial regression was used to estimate suicide rate ratios and 95% confidence intervals across outbreak and inter-outbreak periods during the pandemic, relative to that expected based on pre-pandemic trends, and their associations with economic and outbreak control stringency indicators. Results: There were fewer-than-expected suicides in Taiwan (7%–16% fewer suicides over outbreaks and inter-outbreaks) and South Korea (17% fewer suicides in outbreaks III and IV). Fewer-than-expected suicides were found primarily in the working-age populations aged 25 to 64 years in Taiwan and those aged 45 to 64 years in South Korea. In both countries, fewer-than-expected suicides by charcoal burning during the pandemic were consistently found; the greatest reduction occurred when the outbreak control measures were most restricted. Increased time at residence was associated with decreased suicide rates in South Korea. Conclusion: Taiwan and South Korea showed reduced suicide rates during the COVID-19 pandemic in 2020–2021. Potential reasons for the decrease in suicides may include reduced access to suicide means during outbreaks in the two countries.