Measuring systemic lupus erythematosus activity during pregnancy: Validation of the lupus activity index in pregnancy scale
Article first published online: 5 FEB 2004
Copyright © 2004 by the American College of Rheumatology
Arthritis Care & Research
Volume 51, Issue 1, pages 78–82, 15 February 2004
How to Cite
Ruiz-Irastorza, G., Khamashta, M. A., Gordon, C., Lockshin, M. D., Johns, K. R., Sammaritano, L. and Hughes, G. R. V. (2004), Measuring systemic lupus erythematosus activity during pregnancy: Validation of the lupus activity index in pregnancy scale. Arthritis & Rheumatism, 51: 78–82. doi: 10.1002/art.20081
- Issue published online: 5 FEB 2004
- Article first published online: 5 FEB 2004
- Manuscript Accepted: 6 JAN 2003
- Manuscript Received: 17 MAY 2002
- Fondo de Investigacion Sanitaria, Spain. Grant Number: 99/5007
- Department of Health of the Basque Government
- Lupus UK
- Systemic lupus erythematosus;
- Disease activity;
To validate the Lupus Activity Index in Pregnancy (LAI-P) scale as a diagnostic tool for lupus flares during pregnancy and the puerperium.
The LAI-P is a modified activity scale specific for pregnancy. Thirty-eight pregnant women with systemic lupus erythematosus (SLE) were prospectively followed in 3 clinics specific for lupus in pregnancy. On each visit, LAI-P was calculated. A modified physician global assessment (m-PGA) scale was used as gold standard (0 = no activity, 1 = mild-moderate activity, 2 = severe activity). A change ≥ 0.25 in LAI-P was predefined as a flare according to previous studies in nonpregnant patients. For the purposes of the study, each visit was considered as an independent case.
During the study period, 158 visits took place for a total 621 patient-weeks. Sensitivity to change was high (standardized response mean for LAI-P = 1.6). We found a significant association between LAI-P and m-PGA (P < 0.002 in all regression models performed). Sensitivity, specificity, and positive and negative predictive values were 0.93, 0.98, 0.88, and 0.99. Positive and negative likelihood ratios were 49 and 0.07, respectively.
LAI-P has a high sensitivity to changes in lupus activity, a significant correlation with m-PGA, and high sensitivity, specificity, predictive values, and likelihood ratios for diagnosing SLE flares during pregnancy and the puerperium.