Pediatric Rheumatology Online Journal → June 2003 → Health-Related Quality of Life, Disease Activity and Outcome Assessments→ Abstract #32

PREDICTORS OF PAIN IN CHILDREN WITH ESTABLISHED JUVENILE RHEUMATOID ARTHRITIS

P. N. Malleson,¹ K. Oen,² D. A. Cabral,¹ R. E. Petty,¹ A. M. Rosenberg,³ M. Cheang.⁴

¹Pediatrics, UBC, Vancouver, BC, Canada; ²Pediatrics, Univ. MB, Winnipeg, MB, Canada; ³Pediatrics, Univ. SK, Saskatoon, SK, Canada; ⁴Community Health Services, Univ. MB, Winnipeg, MB, Canada

Although pain is a major symptom in juvenile rheumatoid arthritis (JRA), it has not been extensively studied, and most reports include only a fairly small number of children.
Objectives: To describe, in a large cohort of children with JRA followed at 3 Canadian centres, the demographic, and disease-related variables which might affect pain. This cohort has been previously reported (1).
Methods: All children with JRA (1977 ACR criteria) with Pain over the previous week was measured using a 10 cm visual analogue scale (VAS). Variables studied included JRA subtype, age at onset, disease duration, active joint count, physician global assessment of disease activity (PGA), duration of morning stiffness, sex, race.
Univariate analyses were performed and all significant variables were entered into a stepwise multiple regression analysis.
Results: 388 subjects completed a VAS for pain, and had sufficient data for the analyses.
Univariate Analyses:Active disease duration, active joint count, PGA, morning stiffness, age at study, race, and onset subtype, were significant variables.
Multiple Regression Analyses: 301 subjects had enough data (excluding morning stiffness) for the analyses. Only 22% of the pain variation could be explained. Significant independent variables were disease activity by PGA, disease duration, and age at study. When data on morning stiffness (195 subjects) were included, the proportion of variation explained increased to 27%.
Summary: Similar to the findings of other smaller studies only a relatively small proportion of pain variance can be explained by demographic or disease-related variables. These data emphasize the need to evaluate other factors including psychosocial variables to fully explain pain in JRA.

(1)Oen K et al. Disease course and outcome of juvenile rheumatoid arthritis in a multicentre cohort. J Rheumatol 2002; 29:1989-1999.