Illness behaviour in patients with arthritis

To determine if there are specific patterns of illness behaviour in patients with arthritis, and if abnormal patterns of illness behaviour are associated with withdrawal from trials of anti-inflammatory drugs, and to examine which aspects of illness behaviour are perceived by rheumatologist to be related to the disease process.

The illness behaviour questionnaire (IBQ) was administered to 211 patients with rheumatoid arthritis (RA) and 107 patients with osteoarthritis (OA) participating in five drug trials of NSAIDs at the beginning of the studies, and was commented upon by 17 clinical rheumatologists.

Factor analysis of 211 patients with RA produced a unique factor solution. RA patients were more preoccupied with their illness and its effects and worried more about their health than patients with OA. Patients who withdrew from drug trials showed behaviour patterns similar to those of chronic pain patients, and different from those of patients who completed the studies. When asked to account for a rheumatoid patient's response to the IBQ, rheumatologists focused on physical symptoms and did not recognise some of the psychological issues which patients saw as being relevant.

We have demonstrated differences in illness behaviour between patients with OA and with RA. Patients withdrawing from drug trials of NSAIDs showed differences in illness behaviour compared with those successfully completing the trials. Rheumatologists underestimated the impact of the disease on their RA patients' psychological well being.