Applicability of a health status model to osteoarthritis.

A five-component model of health status has been operationalized by the Arthritis Impact Measurement Scales (AIMS) to serve as a core for the health status assessment of individuals with rheumatoid arthritis (RA). These five components of health status are Lower Extremity Function, Upper Extremity Function, Affect, Symptom, and Social Interaction. To test the utility of this model, this study examines the stability and the applicability of the five-component model in a different rheumatic disease, osteoarthritis (OA). The model displays similar characteristics between OA and RA for Upper Extremity Function, Affect, and Social Interaction. Pain, however, appears to be more strongly associated with Physical Activity in the OA sample, suggesting that pain as a measured symptom of OA is closely related to ambulation, while pain as a symptom of RA may be more a manifestation of joint involvement and less dependent upon walking and climbing. This study presents the AIMS as a means of assessing five components of health status in either OA or RA.