Background There is contradictory evidence on the association between health check-ups and future morbidity. Among the general population, those with high socioeconomic position participate more often in health check-ups. The main aims of this study were to analyse if attendance to health check-ups are socioeconomically patterned and affect sickness absence over a 10-year follow-up.

Methods This register-based follow-up study included municipal employees of the City of Helsinki. 13 037 employees were invited to age-based health check-up during 2000–2002, with a 62% attendance rate. Education, occupational class and individual income were used to measure socioeconomic position. Medically certified sickness absence of 4 days or more was measured and controlled for at the baseline and used as an outcome over follow-up. The mean follow-up time was 7.5 years. Poisson regression was used.

Results Men and employees with lower socioeconomic position participated more actively in health check-ups. Among women, non-attendance to health check-up predicted higher sickness absence during follow-up (relative risk =1.26, 95% CI 1.17 to 1.37) in the fully adjusted model. Health check-ups were not effective in reducing socioeconomic differences in sickness absence.

Conclusions Age-based health check-ups reduced subsequent sickness absence and should be promoted. Attendance to health check-ups should be as high as possible. Contextual factors need to be taken into account when applying the results in interventions in other settings.