1Department of Medicine, Tuen Mun Hospital, Hong Kong, China
2Department of Medicine, Ohio State University Medical Center, Columbus, Ohio, USA
- Dr. Chi Chiu Mok (MD, FRCP), Department of Medicine, Tuen Mun Hospital, Tsing Chung Koon Road, New Territories, Hong Kong, SAR China Email: ccmok2005{at}yahoo.com
Objectives: To study the sensitivity and specificity of vitamin D deficiency for predicting disease activity and damage of systemic lupus erythematosus (SLE) in comparison with anti-dsDNA and anti-C1q. Methods: Consecutive patients who fulfilled four or more ACR criteria for SLE were studied. Levels of 25-hydroxyvitamin D3, anti-C1q, anti-dsDNA and complement levels were measured. Relationship among these markers, concurrent disease activity and damage scores of SLE was studied by Spearman’s rank correlation method. Results: In total, 290 SLE patients were studied (95% women; mean age 38.9 ± 13.1 years; SLE duration 7.7 ± 6.7 years). Clinical or serological lupus activity (SLEDAI ≥ 1) was present in 225 (78%) patients. Vitamin D deficiency (< 15 ng/ml) was detected in 78 (27%) patients. Levels of 25-hydroxyvitamin D3 correlated inversely with the clinical SLE disease activity score (Rho = −0.26; p < 0.001). A negative correlation was also observed between 25-hydroxyvitamin D3 and anti-dsDNA levels (Rho = −0.13; p = 0.02), or anti-C1q (Rho = −0.14; p = 0.02). However, there was no significant relationship between levels of 25-hydroxyvitamin D3 and complement C3 (Rho = 0.09; p = 0.12) or C4 (Rho = 0.09; p = 0.13). Both 25-hydroxyvitamin D3 deficiency and anti-C1q were more specific but less sensitive than anti-dsDNA for concurrent clinical renal and non-renal SLE activity. Levels of 25-hydroxyvitamin D3, anti-dsDNA or anti-C1q did not correlate significantly with the SLE damage scores. Conclusions: 25-hydroxyvitamin D3 correlated inversely and significantly with clinical SLE activity, anti-C1q and anti-dsDNA titers, but not with complement levels or damage scores. Deficiency of 25-hydroxyvitamin D3 was as specific as anti-C1q, but less sensitive than anti-dsDNA, for detecting concurrent renal and non-renal clinical activity of SLE.
- Received April 29, 2011.
- Accepted August 4, 2011.
- © The Author(s), 2011. Reprints and permissions: http://www.sagepub.co.uk/journalsPermissions.nav