Long-term sickness absence : Aspects of society, work, and family

Sammanfattning: Sickness absence has varied considerably in Sweden over time and increased substantially between 1997 and 2002, especially among women. The composition of such absence has also changed in that there have been increases in sick leave due to mental illness, prolongation of sickness absence periods, and a larger proportion of women than men on long-term sick leave. The general aim of the research presented in this thesis was to identify societal and work- and health-related factors underlying the fluctuations in long-term sickness absence (LTSA) in Sweden over the last two decades. Another objective was to identify important risk factors for LTSA among women and men in the working population, considering characteristics of work, family, and individual. In Paper I, aggregated monthly data (December 1992 September 2008) were used to assess structural factors associated with variations in the number of ongoing spells of LTSA (> 59 days). Although specific changes in the sickness insurance scheme may have had an impact, no consistent pattern of associations was found. Furthermore, in contrast to previous studies, the present findings indicated that the composition of the labour force was less relevant for explaining variations in LTSA over the last decades. Instead, it emerged that LTSA was associated with public health indicators such as alcohol sales and factors connected with working conditions and worker health. Paper II employed two similar cross-sectional case-control studies covering 1986?1989 and 2002. The aim was to investigate changes over time in risk factors for LTSA and changes in the fraction of LTSA attributable to these risk factors. Both studies were based on samples of longterm sick listed (> 59 days) and samples of employed in ages 20 to 64 as a comparison group. The results indicate an association between female sex and LTSA in 2002. Also, different aspects of the psychosocial work environment and the job situation were more pertinent risk factors for LTSA in 2002 than in the late 1980s. Still, the relevance of an adverse physical work environment is evident for both male and female employees. An increased population at risk over time contributed substantially to LTSA, and the most evident examples were an ageing workforce, adverse psychosocial work environments, and overweight or obesity. The specific aim of the research reported in Paper III was to investigate the relevance of the demand-control model and social support in predicting LTSA, and to identify gender- and employment-sector-specific patterns. The data from 2002 used in Paper II were analysed. Associations with LTSA were found for weak social support and high-strain jobs among both sexes, and for active jobs among women. The relevance of the demand-control model for LTSA was more evident in the private sector than in the public sector. Paper IV presents a longitudinal cohort study of employees aged 25 50, which was performed to elucidate the association between work-to-family and family-to-work interference and LTSA (> 14 days). The overall association between work-family interference in 2004, and subsequent LTSA during follow-up in 2005 was weak. However, among men with higher socioeconomic status, and to some extent also among women taking the main responsibility for housework and family, interference from work-to-family was associated with LTSA. In conclusion, the major finding of the current research is that the deterioration in psychosocial work environments during the 1990s was an important factor leading to increased LTSA between 1997 and 2002. Moreover, the rise in LTSA was reinforced by other changes, such as an ageing workforce and changes in lifestyle factors. The adverse psychosocial work environments are significant not only because they are pertinent risk factors for LTSA, but also because they have become more common within the working population. With dual-earner families as the dominant norm in Sweden, balance between work and family also represents a factor that affects worker health and LTSA.