Disability Retirement Socioeconomic Differences and Health Outcomes

Disability retirement has implications for public health and the economy, and thus generates strong interest in terms of its causes and consequences. The major predictors include deteriorating health and work ability as well as socioeconomic factors. A comprehensive understanding of the mechanisms through which a low socioeconomic position is associated with an increased risk of disability retirement would help direct interventions to high-risk groups. Socioeconomic position and other key socio-demographic factors also shape the retirement process, thereby modifying health outcomes after the transition. Mental ill health is playing an increasingly important role in work disability, and has attracted much attention as a cause of early retirement. However, less is known about the subsequent mental-health and other associated health outcomes. This study focuses on the socioeconomic differences in disability retirement and the influences of socio-demographic factors on mental health and mortality in relation to the transition. The study was based mainly on register data on a representative sample of the Finnish population including longitudinal records from various administrative sources linked together by Statistic Finland, but also included survey data on the Helsinki Health Study employee cohort linked to register data. Disability retirement was used as an outcome measure in the first part of the study. In the second part further outcomes of mental health and mortality were observed in relation to the transition to disability retirement. Cox proportional hazard and linear regression models were used in the analyses. Those in lower socioeconomic positions had a higher risk of all-cause disability retirement as measured by education and occupational social class in particular, but also by household disposable income. Part of the effect of each of these three socioeconomic factors was nevertheless explained by or mediated through the other two. Social-class differences were particularly large in the case of retirement on the grounds of musculoskeletal diseases. Much of the association between social class and disability retirement was mediated through physical working conditions, although job control also played a part, particularly in retirement on the grounds of mental disorders. The contribution of health behaviours to the association between social class and disability retirement was modest regardless of the underlying diagnostic category. Depressive morbidity measured via purchases of antidepressant medication decreased after disability retirement, following a pre-retirement increase. Such changes in depressive morbidity were more pronounced in the case of retirement on the grounds of mental disorders, particularly depression. Among younger adults there was a bigger increase in antidepressant medication before retirement, and a smaller decrease afterwards. The modifying effects of gender, social class and living arrangements were more modest. Compared to the general population, those who retired on the grounds of depression and other mental disorders had a high mortality risk, particularly from unnatural and alcohol-related causes. This excess mortality was generally more pronounced among younger adults, those in higher social classes, and those living with a partner and children, particularly in the case of unnatural and alcohol-related causes of death. The absolute level of mortality was not always the highest in these sociodemographic groups, however. Socioeconomic and socio-demographic factors play an important role in disability retirement in terms of both its causes and consequences. Education, social class and income are not interchangeable as determinants, both showing independent and interdependent pathways. Improvements especially in physical working conditions among those in lower social classes could reduce socioeconomic differences as well as the overall incidence of disability retirement in the population. It seems that, post-retirement, a high socioeconomic position and family ties have only limited protective effects against mental ill health and mortality. Among those under the age of 45, disability retirement is associated with particularly poor health outcomes later on, including prolonged depressive morbidity and a high risk of mortality especially from unnatural causes. Particular attention should therefore be paid to younger adults in terms of mental ill health, work disability and other social problems.