Voting is a stronger determinant of mortality than education: a full-electorate survival analysis with 21-year...

Although voting is recognised as a social determinant of health, the association between electoral participation and subsequent mortality at an individual level has not been established.

To assess whether voters and non-voters differ in mortality risk.

We used register-based information on electoral participation in the 1999 parliamentary elections from the full electorate of at least 30-year-old Finnish citizens living in mainland Finland linked to registers containing sociodemographic and mortality information by Statistics Finland. Mortality was assessed with Cox proportional hazards regression models, with follow-up until the end of 2020 (n=3 185 572 individuals; 58 133 493 person-years; 1 053 483 deaths).

The age-adjusted HR of non-voters compared with voters for all-cause mortality was 1.73 (95% CI 1.72 to 1.74) for men and 1.63 (95% CI 1.62 to 1.64) for women. These differences were strongest for external causes of death and for younger age groups. Among the older (age ≥75 years) population, voting men had lower mortality than non-voting women. The difference in mortality between non-voters and voters was stronger than between those with basic and higher education.

Due to a strong relationship, information on voting contributes to a more comprehensive analysis of social differentials in mortality.