The role of socioeconomic indicators on non-alcohol and alcohol-associated suicide mortality among women in Finland. A register-based follow-up study of 12 million person-years.

This study was to analyse the effects and interrelationships of three socioeconomic indicators--education, occupation-based social class and income--on non-alcohol and alcohol-associated suicide mortality among women in Finland. The register data used comprised the 1990 census records linked to the death register for the years 1991-2001 for women who were 25-64 years old in 1990. Adjusted relative mortality rates and the relative index of inequality (RII) were estimated using Poisson regression. The study population experienced 1926 suicides, of which 563 (29%) had alcohol intoxication as a contributory cause. The age-adjusted effects of education on non-alcohol associated suicide were modest, while social class and income related inversely and strongly. The effect of social class was partly mediated by income, and social class explained income differences to some extent. The associations between these socioeconomic indicators and alcohol-associated suicide were stronger, and following adjustment for each other large effects were left for education, social class and income. Further adjustment for living arrangements had little effect on socioeconomic differences in both types of suicide, but practically all of the effects of income and some of education and social class were mediated by employment status. In conclusion, current material factors are hardly the main underlying drivers of socioeconomic differences in suicide among Finnish women. Low social class proved to be an important determinant of suicide risk, but the strong independent effect of education on alcohol-associated suicide indicates that the roots of these differences are probably established in early adulthood when educational qualifications are obtained and health-behavioural patterns set.