The Magnitude of Occupational Class Differences in Sickness Absence: 15-Year Trends among Young and Middle-Aged Municipal Employees

Background: Our aim was to examine the magnitude of relative occupational class differences in sickness absence (SA) days over a 15-year period among female and male municipal employees in two age-groups. Methods: 18-34 and 35-59-year-old employees of the City of Helsinki from 2002 to 2016 were included in our data (n = ~37,500 per year). Occupational class was classified into four groups. The magnitude of relative occupational class differences in SA was studied using the relative index of inequality (RII). Results: The relative occupational class differences were larger among older than younger employees; the largest differences were among 35-59-year-old men. Among women in both age-groups the relative class differences remained stable during 2002-2016. Among younger and older men, the differences were larger during the beginning of study period than in the end. Among women in both age-groups the RII values were between 2.19 (95% confidence intervals (CI) 1.98, 2.42) and 3.60 (95% CI 3.28, 3.95). The corresponding differences varied from 3.74 (95% CI 3.13, 4.48) to 1.68 (95% CI 1.44, 1.97) among younger and from 6.43 (95% CI 5.85, 7.06) to 3.31 (95% CI 2.98, 3.68) among older men. CONCLUSIONS Relative occupational class differences were persistent among employees irrespective of age group and gender. Preventive measures should be started at young age.