Constitutional symptom Occupational disability 2021-03-07T23:02:06Z This is a general term that denotes a reduced ability to perform the work that one performed prior to an illness, and may be related to pain, cognitive dysfunction, fatigue or other physical disabilities. This term does not intend to include or exclude legal definitions of occupational disability. It is included in the HPO because inability to work is a frequent manifestation of disease comparable in some ways to impairment of activities of daily living.