Current risk factors for work disability associated with rheumatoid arthritis: recent data from a US national cohort.
OBJECTIVE
To explore, using recent data, whether and how risk factors for rheumatoid arthritis (RA) work disability may differ from previous studies.


METHODS
Subjects were 953 individuals with RA from a US cohort who provided data semiannually over 18 months (years 2002-2005). A nested case-control design was used with matching on time of baseline data collection. All subjects were employed at baseline; cases were consistently not employed at followup, whereas controls remained employed. Hierarchical conditional logistic regression assessed the roles of demographic, RA disease, general health, and work factors as predictors of work disability. Recursive partitioning and causal modeling procedures were also used.


RESULTS
Sample characteristics were mean age 51 years, 82% female, and 92% white. Older age (odds ratio [OR] 1.2, 95% confidence interval [95% CI] 1.1-1.4) and lower income (OR 1.7, 95% CI 1.0-2.7) predicted work disability, whereas more hours worked (OR 0.9, 95% CI 0.8-0.9) and preference to work full time (OR 0.2, 95% CI 0.1-0.4) or part time (OR 0.4, 95% CI 0.2-0.6) versus not to work were protective in the regression analysis. In recursive partitioning analyses, RA disease factors predicted work disability among older subjects, and functional limitation was the fourth most important factor. Job physical demand was not a significant or important factor.


CONCLUSIONS
In this contemporary data from a large RA cohort, older age, lower income, fewer working hours, and preference not to work were the risk factors for work disability. The impact of disease factors was limited to subjects ages >or=56 years. Job physical demand level had little impact.
Allaire
Saralynn
S
Boston University School of Medicine, Boston, Massachusetts 02118, USA. sallaire@bu.edu
Wolfe
Frederick
F
Niu
Jingbo
J
LaValley
Michael P
MP
Zhang
Bin
B
Reisine
Susan
S
D000328:Adult; D000367:Age Factors; D001172:Arthritis, Rheumatoid / Q000150:complications*; D016022:Case-Control Studies; D016208:Databases, Factual; D004185:Disability Evaluation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D012307:Risk Factors; D012720:Severity of Illness Index; D012959:Socioeconomic Factors; D014481:United States