Life satisfaction and suicide: a 20-year follow-up study

Area of Science:

• Psychiatry and Behavioral Sciences
• Epidemiology
• Public Health

Background:

• Investigating predictors of suicide is crucial for public health initiatives.
• Longitudinal studies are essential to understand the temporal relationship between psychological states and mortality.
• The role of general life satisfaction as a predictor of suicide risk in the general population remains an important research question.

Purpose of the Study:

• To determine if self-reported life satisfaction predicts suicide over a 20-year period.
• To examine the long-term impact of life dissatisfaction on suicide risk in adults.
• To explore potential mediating factors, such as health behaviors, in the relationship between life satisfaction and suicide.

Main Methods:

• A nationwide sample of 29,173 Finnish adults (aged 18-64) from the Finnish Twin Cohort participated.
• Life satisfaction was assessed using a four-item scale (score range 4-20; higher scores indicate greater dissatisfaction).
• Mortality data, including suicide, were obtained from the national registry and analyzed using Cox regression.

Main Results:

• Life dissatisfaction at baseline was significantly associated with an increased risk of suicide over 20 years (age-adjusted hazard ratio=3.02).
• The association between life dissatisfaction and suicide risk was stronger in the first decade of follow-up and showed a dose-response relationship.
• Life dissatisfaction predicted suicide risk even after adjusting for age, sex, health status, alcohol consumption, smoking, and physical activity (hazard ratio=1.74).

Conclusions:

• Life dissatisfaction has a demonstrable long-term effect on suicide risk.
• Poor health behaviors may partially mediate the link between life dissatisfaction and suicide.
• Life satisfaction appears to function as a comprehensive indicator of overall health.