The Interplay between Multimorbidity, Physical Work Demands and Work Ability: Cross-Sectional Study among 12,879 Senior Workers

Background: Aging increases the risk of chronic diseases, which can challenge the ability to work and thereby push senior workers out of the labour market. This study investigates the association between non-communicable diseases (NCDs) and work ability among workers ≥50 years (senior workers) with physically demanding and sedentary work, respectively. Methods: In the SeniorWorkingLife study, 12,879 senior workers replied to a questionnaire survey on work and health in 2018. Associations between the type and number of NCD and work ability (scale 0–10) were modelled using a general linear model adjusting for potential confounders and combined with model-assisted weights from national registers. Results: A higher number of NCD (multimorbidity) was progressively associated with a lower work ability (trend test, p-value < 0.001). Physical work influenced the association between the number of NCDs and work ability. For specific diseases, mental disorders, including burn-out syndrome (least square mean difference (LSMD): −1.46, 95% CI: −1.61 to −1.32) and stress ( LSMD: −1.18, 95% CI: −1.29 to −1.07), demonstrated a stronger association with a lower work ability compared with somatic diseases, such as back diseases (LSMD: −0.72, 95% CI: −0.80 to −0.64). Conclusions: Multimorbidity was progressively associated with a lower work ability in senior workers, especially among those with physical work.