Article Text
Abstract
Background and objective Increasing longevity in combination with low fertility decreases the dependence ratio: a larger proportion of the population becomes dependent of the work of a smaller proportion. Consequently there is a political demand to continue working into higher ages. One occupational health aspect of this development is potential impairment of healthy ageing. We hypothesised an increased risk of myocardial infarction and major depression due to occupational strain in healthy elderly employees who continue working.
Methods The risk of myocardial infarction and hospital treated major depression following non-disability age-related retirement was examined in a Danish national cohort of employees born between 1932 and 1948 with up to 7 years of follow-up from 60 years of age in the calendar period from 1992–2007. Information on retirement and medical diagnoses was retrieved from registers with national coverage. Only employees free of disease at baseline were included. Cox regression models were adjusted for effects of age, gender, income, occupational position, education, cohabitation and immigrant status.
Results Analyses of incident cases of myocardial infraction during follow-up included 614 914 employees while analyses of the prevalence of major depression included 536 628 employees. The adjusted hazard ratio for myocardial infarction (n = 11 697 cases, 3%) in retired compared to non-retired employees was 1.09 (95% CI: 1.06–1.14) and for major depression it was 1.34 (95% CI: 1.22–1.48). The risk was not modified by occupational exposure categorised into knowledge work, client work or manual work.
Conclusions This study does not support the hypothesis that retirement reduces risk of myocardial infarction or major depression. On the contrary continued work may be protective although findings may also be explained by health related selection due to non-disability retirement that was not accounted for.