Occupational physical activity differentially affects the risk for developing later-onset Crohn's disease and ulcerative colitis among middle-aged and older populations.

Our study revealed that the risk for later-onset of UC, but not CD, was associated with longest-held 'service' and 'manufacture' work. The risk by OPA levels was inversely associated between CD and UC. Further studies are needed by follow-up method for long-term effects of physical activity.