Measuring the impact of osteoarthritis has traditionally focused on the disease (measures of impairment), functional disability and latterly, general health status or quality of life. This paper highlights the importance of measuring the wider personal and social consequences of OA both at a population and an individual patient level.
The World Health Organisation definition of handicap is used to describe this wider impact of disease and measures of handicap, both generic and disease-specific are reviewed. The measurement of handicap in OA is illustrated by the use of the Disease Repercussion Profile in a clinical trial of orthopaedic out-patients with OA and low back pain. These data are compared to routine clinical handicap data collected on consecutive patients with rheumatoid arthritis attending a different outpatient clinic.
OA patients reported handicap in six areas of their lives: functional and social activities, relationships, socio-economic status, emotional well-being and body image. The prevalence was similar to that reported by RA patients. OA patients reported more severe handicap than RA patients in each of the 6 areas (F ratios 4. 97-55.67) and the differences were statistically significant (P values 0.03-0.0001) for all dimensions except functional and social handicap. The LBP patients scored slightly more severe handicap on all dimensions than the OA patients but these differences did not reach statistical significance. However, they scored significantly more severe handicap than the RA patients (F ratios 8.49-174.72, P< 0.0001).
These data suggest that the psychosocial impact of OA may have been underestimated and highlight the importance of going beyond disability in assessing the impact of OA. Measurement of the wider impact of OA can be achieved using disease-specific and generic measures of handicap. The choice of tool will depend upon the setting (research or clinical practice) and the purpose of measurement.