The impact of illness representations and disease activity on adjustment in women with rheumatoid arthritis: A longitudinal study

This longitudinal study examined the extent to which illness representations and disease indicators predict physical and psychological outcomes in patients with rheumatoid arthritis. Baseline data was collected on 75 women attending an out-patient clinic in the west of Ireland. Data was available for a final study sample of 52 at two-year follow-up. Disease status was assessed by physician ratings of joint involvement and laboratory indices of erythrocyte sedimentation rate and c-reactive protein. The Illness Perception Questionnaire and the Arthritis Impact Measurement Scale were administered during a semi-structured interview held at yearly intervals over a three-year period. In hierarchical regression analyses the illness representations accounted for 17-33% of the variance in measures of physical function, pain, depression and anxiety. All relationships were in the expected direction. Disease status explained 10-15% of the variance in illness related aspects of physical function and pain and predicted pain over time. Illness perceptions outweighed the impact of medical disease status on concurrent physical and psychological adjustment. Interventions based on understanding and modifying illness representations may prove useful in facilitating patient well-being.