Investigating the relationship between cross-national suicide rates and COVID-19 first and second waves spread across the world: An exploratory study

INTRODUCTION: COVID-19 spreads between people in close contact. Social isolation, which is linked with increased suicide risk, prevents COVID-19 from spreading. Suicide and COVID-19 may therefore represent two antagonistic phenomena. Specifically, we tested whether previous cross-national suicide rates inversely correlate with COVID-19 cases and deaths across countries. MATERIAL AND METHODS: We ran unadjusted bivariate correlations between the most updated (2016) cross-national Age-Standardised suicide rates and COVID-19 cumulative cases and deaths (as of: 30/08/2020, 11/10/2020 and 30/05/2021) across countries; and we controlled for WHO Income group, WHO region, suicide data quality, and urbanicity. RESULTS: Suicide rates negatively correlated with COVID-19 cumulative cases up to 30/08/2020 (r = −0.14, P = .064) and up to 11/10/2020 at an almost significant level (r = −0.149, P = .050) across 174 countries. As of 11/10/2020 this correlation became significant when controlling for WHO region (r = −0.17, P = .028), data quality (r = −0.181, P = .017) and urbanicity (r = −0.172, P = .039); and as of 30/08/2020 when adjusting for WHO region (r = −0.15, P = .047) and data quality a (r = −0.16, P = .036). No significant correlations between suicide rates and COVID-19 deaths were found. CONCLUSIONS: There seems to be an inverse correlation between previous cross-national suicide rates and COVID-19 cumulative cases across countries. Suicide and COVID-19 appear to behave, to some degree, as antagonistic phenomena, which challenges their prevention.