Increasing trends in suicide mortality of working-age men and women during and after the early-1990s economic recession in Sweden: a national registry-based repeated cohort study

INTRODUCTION:  The objective of this study was to evaluate the recent trends in income-based inequality in suicide mortality during and after the economic recession in the early 1990s in Sweden.

METHODS:  We conducted a national registry-based repeated cohort study with three years of follow-ups using 15 annual cohorts between 1990 and 2004, gathering information on suicide mortality for all working-age Swedish men and women aged between 30 and 64 years. Then we conducted temporal trend analysis using Poisson regression with generalized estimating equations to statistically confirm the trajectories observed.

RESULTS:  Among men, suicide mortality rate reduced by 45.8% in the highest income quintile but the reduction was only 27.6% among the poorest during the period. Among women, the mortality reduced by 50.4% in the richest, but increased by 5.8% among the poorest. Among men, the rate differences (per 100,000 population) between the lowest and highest income quintiles was 25.5 (95% confidence intervals: 18.6-32.4) in 1990 but began to increase after 1994 to the maximum of 31.8 (25.4-38.3) in 2000 and then declined to 20.4(14.9-25.9) in 2004. Among women, rate differences began to increase from 7.8 (2.9-12.7) to 9.0 (4.7-13.3) after 1994. Similar trends were seen in the evaluation of disparities using alternative absolute and relative indices, which were confirmed by the trend analyses.

CONCLUSIONS:  Income-based inequalities in suicide mortality have increased for men and women after 1994 in both absolute and relative terms. Economic recovery was seen during the late 1990s. Therefore, although more formal and direct tests are needed, these increasing inequalities in suicide mortality in later years might be due to both the lag effects of economic recession and the government’s structural reforms.