The association between unemployment and suicide among employed and unemployed people in Hong Kong: A time-series analysis

Background: Unemployment is associated with suicide. However, it is unclear whether the influence of unemployment is consistent on suicide across subgroups with different employment status. This study aimed to explore the immediate and delayed association between unemployment and suicide among unemployed and employed people in Hong Kong. Methods: Quarterly statistics on labor force, unemployment rate and suicide count by employment status in Hong Kong (2003-2019) were obtained from the Hong Kong Census and Statistics Department and the Coroner's Court suicide reports. Separate negative binomial autoregressive regressions were used to investigate associations between unemployment and suicide among employed and unemployed people. The models controlled for linear and non-linear time trends, seasonal variations, the number of suicide cases, Consumer Price Index, and gender ratios of the labor force in the previous quarter. Results: After controlling for all covariates, every 1% increase in the present unemployment rate was associated with a 15% increase in the suicide rate among the employed people in the current quarter (Incidence Rate Ratio (IRR) = 1.14, 95% CI = 1.01-1.28), and a 13% decrease in the suicide rate among the unemployed in the next quarter (IRR = 0.87, 95% CI = 0.78-0.98). Limitations: Most recent data on suicide cannot be obtained due to processing time of death investigation. Conclusions: The influence of unemployment differed on suicide by employment status in different time periods. Employed and unemployed people have different needs in different economic conditions. Hence, it is important to provide timely, targeted and effective measures for suicide prevention to the specific group.