Regional radiographic damage and functional limitations in patients with ankylosing spondylitis: Differences in early and late disease
Article first published online: 30 JAN 2013
Copyright © 2013 by the American College of Rheumatology
Arthritis Care & Research
Volume 65, Issue 2, pages 257–265, February 2013
How to Cite
Ward, M. M., Learch, T. J., Gensler, L. S., Davis, J. C., Reveille, J. D. and Weisman, M. H. (2013), Regional radiographic damage and functional limitations in patients with ankylosing spondylitis: Differences in early and late disease. Arthritis Care Res, 65: 257–265. doi: 10.1002/acr.21821
- Issue published online: 30 JAN 2013
- Article first published online: 30 JAN 2013
- Accepted manuscript online: 6 OCT 2012 10:26AM EST
- Manuscript Accepted: 31 JUL 2012
- Manuscript Received: 20 MAR 2012
- NIH/National Institute of Arthritis and Musculoskeletal and Skin Diseases. Grant Numbers: PO1-052915, RO1-AR-048465
- Cedars-Sinai General Clinical Research Center. Grant Number: MO1-RR-00425
- University of Texas at Houston General Clinical Research Center. Grant Number: MO1-RR-02558
- The Rosalind Russell Center for Arthritis Research at the University of California, San Francisco
- Intramural Research Program
- National Institute of Arthritis and Musculoskeletal and Skin Diseases/NIH
Both radiographic damage and functional limitations increase with the duration of ankylosing spondylitis (AS). We examined whether radiographic damage contributed more to functional limitations in late AS than in early AS, and if the strength of association varied with the anatomic region of damage.
In this cross-sectional study of 801 patients with AS, we examined associations of the lumbar modified Stoke Ankylosing Spondylitis Spine Score (mSASSS), the cervical mSASSS, lumbar posterior fusion, cervical posterior fusion, and hip arthritis with the Bath Ankylosing Spondylitis Functional Index (BASFI) and the Health Assessment Questionnaire modified for the spondyloarthritides (HAQ-S).
Higher lumbar and cervical mSASSS scores were associated with more functional limitations, but there was an interaction between mSASSS scores and the duration of AS, such that the strength of their association with functional limitations decreased with increasing duration of AS. Cervical posterior fusion was associated with worse functioning independent of mSASSS scores. Hip arthritis was significantly associated with functional limitations independent of spinal damage measures. Among patients with AS duration ≥40 years, the number of comorbid conditions accounted for most of the variation in functioning. Results were similar for both the BASFI and the HAQ-S.
Although both radiographic damage and functional limitations increase over time in AS, the relative contribution of radiographic damage to functional limitations is lower among patients with longstanding AS than with early AS, suggesting patients may accommodate to limited flexibility. Damage in different skeletal regions impacts functioning over the duration of AS. Functional limitations due to comorbidity supervene in late AS.