To multidimensionally assess fatigue in rheumatoid arthritis (RA) and to evaluate the impact of fatigue on health-related quality of life (HRQOL).
The study was conducted in 1999 among 490 RA patients with varying disease duration. Fatigue was measured with the Multidimensional Fatigue Inventory (MFI-20) and HRQOL with a validated Dutch version of the RAND 36-Item Health Survey. We evaluated the impact of fatigue on HRQOL by multiple linear regression analyses taking into account RA-related pain and depressive symptoms.
Different aspects of fatigue selectively explained different dimensions of HRQOL. The MFI-20 was entered last to the linear regression models, resulting in an additional increase of explained variance of 1% (mental health) to 14% (vitality).
The multidimensional portrayal of RA-related fatigue can be used to develop intervention strategies targeted to specific aspects of fatigue. Fatigue, supplementary to RA-related pain and depressive symptoms, appears to be a feasible and treatable target in the clinical management of RA to increase HRQOL.