Economic factors and suicide rates: associations over time in four countries.

OBJECTIVE

Suicides account for more than 30,000 deaths per year in the US alone. Suicide rates change over time, and the factors influencing them remain poorly understood. Economic factors, in particular unemployment, have been suggested as a major influence. However, the evidence for this has been inconsistent, which may be partly explained by shortcomings of the statistical methods used.

METHODS

Time series analytical techniques (unit root and co-integration tests) were applied to test the associations over time between economic factors, i.e. unemployment, real gross domestic product per capita (RGDP) and the consumer price index (CPI) and death rates by suicide as collected by national agencies in the UK (1901-2006), US (1900-1997), France (1970-2004) and Italy (1970-2001). Traditional correlation analyses were used when appropriate.

RESULTS

Co-integration and correlation tests showed a long-run association between economic factors and suicide rates. Increase/decrease of unemployment predicted an increase/decrease of suicide rates over long historical periods and in different nations. RGDP and the CPI were also linked with suicide rates, but this was not consistently so and the direction of the association varied.

CONCLUSIONS

Unemployment is a major factor influencing suicide rates over long periods of time and in different national contexts. It needs to be considered as a confounding factor in evaluations of suicide prevention strategies.