To study additional risk factors for rheumatoid arthritis (RA)-related work disability and to identify the groups of individuals at high risk and the potentially modifiable factors which place them at risk.
A cross-sectional mail survey was conducted among 469 adults with RA. Work disability was defined as unemployment due to RA. A broad range of explanatory factors was examined, including sociodemographic, health, work, support given by others, and commuting difficulty. Employed and work-disabled subjects were compared by t-test and chi-square. Attributable fractions were calculated to assess the predictive value of factors. A recursive partitioning procedure identified individuals at varying risks for work disability, and their characteristics were defined.
The risk factors joint pain and functional status, commuting difficulty, physical demands of the job, and disease duration were important predictors of work disability in both the attributable fraction and recursive partitioning analytic models. Having a professional or administrative job was protective, provided the salary earned was not low. Younger individuals with RA of shorter duration were placed at high risk by potentially modifiable factors. While older persons with RA of long duration were at high risk, modifiable factors could not be identified.
Commuting difficulty, a previously overlooked factor, is an important predictor of RA work disability. Younger individuals with RA of relatively short duration can be placed at high risk by potentially modifiable factors including commuting difficulty, physically demanding jobs, greater joint pain and poor functional status, and nonprofessional/non-administrative jobs.