Long-term sickness absences based on mental disorders by socioeconomic group – trends of prevalence in Finland 2010–2023

Perhoniemi and Blomgren BMC Public Health (2025) 25:1277 https://doi.org/10.1186/s12889-025-22431-x BMC Public Health Open Access RESEARCH Long‑term sickness absences based on mental disorders by socioeconomic group – trends of prevalence in Finland 2010–2023 Riku Perhoniemi1*   and Jenni Blomgren1    Abstract Background Long-term sickness absences (LTSA) are often linked to mental disorders. Up-to-date register-based evidence on the prevalence and trends of LTSA based on mental disorders is lacking, as is understanding of socioeconomic differences. This study examines the trends in prevalence of LTSA based on mental disorders in various socioeconomic groups both employed and outside employment. Methods Finnish 18–67 years old non-retired residents were included in yearly study populations for 2010–2023. LTSA prevalence was examined through receipt of compensated sickness allowance. Yearly age-adjusted prevalences of LTSA were calculated for six socioeconomic groups using direct standardization. Adjusting for various covariates, relative risks (RR) between socioeconomic groups in LTSA prevalences were then analysed for 2010 and 2023 using Modified Poisson regression models. All analyses were run separately for both sexes, and for all mental disorders combined, for mood disorders, anxiety disorders, and other mental disorders combined. Results The prevalence of LTSA based on mental disorders increased from 2010 to 2023 among all socioeconomic groups and for both sexes, but especially among lower non-manual female employees due to anxiety disorders, and among students and unemployed persons due to mood disorders. Compared to upper non-manual employees, the higher covariate-adjusted relative risks for LTSA based on mental disorders in lower non-manual employees increased slightly during the study period (women: RRs 1,13 to 1,25; men: RRs 1,20 to 1,30). While age-group-standardized trends showed an approximately similar risk for manual workers compared to upper non-manual employees, covariate-adjusted modelling revealed a slightly lower relative risk, most apparent for anxiety disorders (RR in 2023 0,79). Entrepreneurs had a consistently lower relative risk compared to other groups. Conclusions The prevalence of long-term sickness absences due to mood and anxiety disorders have increased among all socioeconomic groups, but register data also reveals group differences in prevalences and trends. Factors related to covid-19 pandemic, intensity of job demands, and buffering resources may explain these differing trends. Employees, but also students and unemployed persons need support to curb the increase in LTSA due to mental disorders. Keywords Long-term sickness absence, Work disability, Socioeconomic position, Population-based study, Register study *Correspondence: Riku Perhoniemi 1 The Social Insurance Institution of Finland, Nordenskiöldinkatu 12, 00250 Helsinki, Finland Introduction In OECD countries, recent years have witnessed an increase in mental disorders [1, 2]. Moreover, the covid19 pandemic, recent global conflicts and their wide financial consequences appear to have exacerbated the mental © The Author(s) 2025. Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/. Perhoniemi and Blomgren BMC Public Health (2025) 25:1277 health crisis [3, 4]. Simultaneously, mental disorders are increasingly associated with long-term sickness absences (LTSA), especially due to common mental disorders such as depression, mood disorders and anxiety disorders. However, while high proportions of sickness absence and benefit spells based on mental disorders have been reported [5, 6], as well as an increase in last decades [7–9], recent register-based international evidence on the prevalence and possible increase is surprisingly very scarce [10]. Moreover, reasons behind the increase in mental disorders and related sickness absences are not well understood, but it is paramount as LTSA based on mental disorders particularly increases the risk for permanent disability [11–16]. One key question is if and how socioeconomic groups differ in LTSA prevalence based on mental disorders, and to what extent there is an increasing trend in different groups. Unraveling trends by socioeconomic group can add to understanding factors behind the increasing general trend. Various studies in Nordic countries have shown an association between lower occupational position and a higher all-cause LTSA risk [17–25]. In these studies, manual workers have had more frequent LTSA spells than non-manual workers. High frequency of also LTSA based on mental diagnoses has been reported among manual and lower non-manual workers [26, 27], although occupational group differences can be smaller than for other diagnosis groups [22]. Finnish studies have further showed an even higher prevalence for routine or lower non-manual workers compared to manual workers [22–24, 27]. As an occupational class, not much is known internationally about sickness absences of entrepreneurs. This is partly because their entitlement to LTSA benefits and LTSA periods’ registration depend on national systems. While several studies have shown a low risk of LTSA [28], Pedersen et al. [29] have interestingly shown that compared to wage earners, self-employed persons actually have a higher risk of LTSA in Denmark. In a Finnish study, the prevalence of LTSA based on mental disorders was lower for entrepreneurs than for other occupational groups or the unemployed [23]. Another socioeconomic difference in LTSA prevalence based on mental disorders may run between those employed and those outside employment. The unemployed, especially long-term unemployed, have poorer average health [30, 31] and may be at particular risk of developing a mental disorder [32]. Harkko’s et al. [33] population-based study found a strong association between unemployment and a risk for future LTSA due to common mental disorders. More generally unemployment has been found to increase the risk Page 2 of 12 of future (...truncated)