Background The impact of retirement on health-related functioning, an important indicator of individual´s ability to function in everyday life, is poorly understood. Thus the aim of this study was to examine the association between transition to retirement, and changes in physical and mental health functioning among Finnish municipal employees.

Methods Follow-upsurvey data were collected among ageing employees of the City of Helsinki, Finland, at three Phases: 1 (2000–2002), 2 (2007) and 3 (2012). Physical and mental health functioning were measured using the Short-Form 36 questionnaire at each Phase. Retirees between Phases 1 and 3 were identified from the national registers of the Finnish Centre for Pensions: Full-time statutory retirement (n=1464), part-time retirement not due to health reasons (n=404) and disability retirement due to health reasons (n=462). Generalised estimating equations were used to study the associations between transition to retirement and changes in health functioning. We also examined whether changes in functioning vary by gender, occupational status, or different health- and life-style factors.

Results Statutory and part-time retirement were not associated with changes in physical health functioning during retirement transition process when adjusting for gender and age (β 0.1, 95% CI −0.3 to 0.5 and −1.0,–1.8 to 0.1, respectively), whereas clear decline was observed among disability retirees (−4.3,–5.4 to −3.2). Higher occupational class before retirement and sedentary lifestyle were associated with greater decline in physical health functioning. Mental health functioning improved during the retirement transition process among statutory and part-time retirees (1.9, 1.4 to 2.4 and 2.0, 1.0 to 3.0, respectively) while no association was observed among disability retirees (−0.3,–1.7 to 1.0).

Conclusion Disability retirement was associated with decrease in physical health functioning, and statutory retirement with a slight improvement in mental health functioning. Evidence on changes in physical and mental functioning during retirement transition process may provide useful information for interventions to promote healthy ageing.