Dr. Schur has received consultant fees, speaking fees, and/or honoraria (more than $10,000) from UpToDate in Rheumatology.
Systemic Lupus Erythematosus
Development and initial validation of a self-assessed lupus organ damage instrument
Article first published online: 30 MAR 2010
Copyright © 2010 by the American College of Rheumatology
Arthritis Care & Research
Volume 62, Issue 4, pages 559–568, April 2010
How to Cite
Costenbader, K. H., Khamashta, M., Ruiz-Garcia, S., Perez-Rodriguez, M. T., Petri, M., Elliott, J., Manzi, S., Karlson, E. W., Turner-Stokes, T., Bermas, B., Coblyn, J., Massarotti, E., Schur, P., Fraser, P., Navarro, I., Hanly, J. G., Shaver, T. S., Katz, R. S., Chakravarty, E., Fortin, P. R., Sanchez, M. L., Liu, J., Michaud, K., Alarcón, G. S. and Wolfe, F. (2010), Development and initial validation of a self-assessed lupus organ damage instrument. Arthritis Care Res, 62: 559–568. doi: 10.1002/acr.20193
- Issue published online: 30 MAR 2010
- Article first published online: 30 MAR 2010
- Manuscript Accepted: 22 DEC 2009
- Manuscript Received: 8 JAN 2009
- National Data Bank for Rheumatic Diseases
- American College of Rheumatology
- Arthritis Foundation
- NIH. Grant Numbers: P60-AR047782, K24-AR002213-05, R01-AR49880, P60-AR047782, K24-AR052401, P01-AR49084
- BIRCWH K12. Grant Number: HD051959
- National Institute of Mental Health
- National Institute of Allergy and Infectious Diseases
- National Institute of Child Health and Human Development
- Office of the Director
- Hopkins Lupus Cohort. Grant Number: AR43727
- National Center for Research Resources. Grant Number: UL1-RR-025005
- National Research Science Award. Grant Number: F32AR054278-01A1
- Arthritis Foundation
- Canadian Institutes of Health Research
- Arthritis Centre of Excellence, University of Toronto
- Lupus Canada
- Lupus Ontario
- Lupus Foundation of Ontario
- British Columbia Lupus Society
- Arthritis and Autoimmune Research Centre Foundation
- The Arthritis Society
The Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI) is a validated instrument for assessing organ damage in systemic lupus erythematosus (SLE). Trained physicians must complete it, thus limiting utility where this is impossible.
We developed and pilot tested a self-assessed organ damage instrument, the Lupus Damage Index Questionnaire (LDIQ), in 37 SLE subjects and 7 physicians. After refinement, 569 English-speaking SLE subjects and 14 rheumatologists from 11 international SLE clinics participated in validation. Subjects and physicians completed the instruments separately. We calculated sensitivity, specificity, Spearman's correlations, and agreement using the SDI as the gold standard. Six hundred five SLE participants in the community-based National Data Bank for Rheumatic Diseases (NDB) study completed the LDIQ and we assessed correlations with outcome and disability measures.
The mean LDIQ score was 3.3 (range 0–16) and the mean SDI score was 1.5 (range 0–9). The LDIQ had a moderately high correlation with the SDI (Spearman's r = 0.50, P < 0.001). Specificities of individual LDIQ items were >80%, except for neuropathy. Sensitivities were variable and lowest for damage, with <1% prevalence. Agreement between the SDI and LDIQ was >85% for all but neuropathy, reduced renal function, deforming arthritis, and alopecia. In the NDB, the LDIQ correlated well with the comorbidity index (r = 0.45), the Short Form 36 physical component scale (r = 0.43), the Medical Research Council dyspnea scale (r = 0.40), disability (r = 0.37), and the Systemic Lupus Erythematosus Activity Questionnaire score (r = 0.37).
The metric properties of the LDIQ are good compared with the SDI. It has construct validity and correlations with health assessments similar to the SDI. The LDIQ should allow expansion of SLE research. Its ultimate value will be determined in longitudinal studies.