Objectives To examine the relative importance of pre-existing chronic conditions versus differences in injury type and subsequent hosptialisations on age differences in absence from work following a work-related injury.

Methods This study used short and long term disability claims (i.e. claims involving time away from work) reported to WorkSafe British Columbia (WSBC) linked with the British Columbia Discharge Abstract Database (DAD) and Medical Services Plan (MSP) at the individual level. We ran a series of nested regression models to examine the impact adjustment for eight different chronic conditions, and injury type and hosptialisations, on attenuating age differences in days of absence from work over the two year period following the injury. Analyses were run separately for men and women.

Results Among men, a clear direct gradient was observed for number of days absent from work and age. Among women there appeared a threshold effect, with no increase in days away from work among 45 - 54 and 55+ year olds relative to 35 to 44 year olds. Pre-existing osteoarthritis, depression, and diabetes, as well as fractures, multiple injuries and hospitalisations were associated with longer absence from work among both men and women. Adjustment for injury type and hospitalisations attenuated differences across age groups among men by approximately 20%. Adjustment for chronic conditions did not attenuate age differences in workers less than 35 years of age, and only marginally attenuated differences among older male workers.

Conclusions The relationship between age and absences from work following a work injury differs for men and women. Age differences in injury type and subsequent hosptialisations are more important pathways in explaining age differences in absence from work among men than pre-existing chronic conditions