History of labour market attachment as a determinant of health status: a 12-year follow-up of the Northern Swedish Cohort

OBJECTIVE: The present study aims at using trajectory analysis to measure labour market attachment (LMA) over 12 years and at examining whether labour market tracks relate to perceived health status. DESIGN: Data were retrieved from a 26-year prospective cohort study, the Northern Swedish Cohort. SETTING AND PARTICIPANTS: All ninth grade students (n=1083) within the municipality of Luleå in northern Sweden were included in the baseline investigation in 1981. The vast majority (94%) of the original cohort participated at the fourth follow-up. In this study, 969 participants were included. MEASURES: Perceived health status (psychological distress and non-optimal self-rated health) at age 42 and the data obtained from questionnaires. RESULTS: We have identified four tracks in relation to LMA across the 12-year period: ‘permanent’, ‘high level’, ‘strengthening’ and ‘poor level’ of attachment. LMA history relates to psychological distress. High level (OR 1.55 (95% CI 1.06 to 2.27)), strengthening (OR 1.95 (95% CI 1.29 to 2.93)) and poor attachment (OR 3.14 (95% CI 2.10 to 4.70) involve higher OR for psychological distress compared with permanent attachment. The overall p value remained significant in the final model (p=0.001). Analyses regarding non-optimal self-rated health displayed a similar pattern but this was not significant in the final model. CONCLUSIONS: Our results suggest that health status in mid-life, particularly psychological distress, is related to patterns of LMA history, to a large part independently of other social risk factors and previous health. Consideration of heterogeneity and time in LMA might be important when analysing associations with perceived health.