Vitamin D insufficiency and deficiency in mexican patients with systemic lupus erythematosus: Prevalence and relationship with disease activity.

OBJECTIVES: To determine and compare the prevalence of vitamin D insufficiency and deficiency in patients with systemic lupus erythematosus (SLE) with and without disease activity.

PATIENTS AND METHODS: We made a comparative, observational, cross-sectional, prospective study of 137 women with SLE according to American College of Rheumatology criteria. Patients with chronic kidney disease, cancer, hyperparathyroidism, pregnancy, and lactation were excluded. Disease activity was assessed using the MEX-SLEDAI score: a score of ≥3 was considered as disease activity. Data were collected on diabetes mellitus, the use of corticosteroids, chloroquine, and immunosuppressants, photoprotection and vitamin D supplementation. Vitamin D levels were measured by chemiluminescent immunoassay: insufficiency was defined as serum 25-hydroxyvitamin D <30ng/ml and deficiency as <10ng/ml.

RESULTS: 137 women with SLE (mean age 45.9±11.6 years, disease duration 7.7±3.4 years) were evaluated. Mean disease activity was 2 (0-8): 106 patients had no disease activity and 31 had active disease (77.4% versus 22.6%). Vitamin D insufficiency and deficiency was found in 122(89.0%) and 4 (2.9%) patients, respectively. There was no significant difference in vitamin D levels between patients with and without active disease (19.3±4.5 versus 19.7±6.8; P=.75). No correlation between the MEX-SLEDAI score (P=.21), photosensitivity, photoprotection, prednisone or chloroquine use and vitamin D supplementation was found.

CONCLUSIONS: Women with SLE had a high prevalence of vitamin D insufficient. No association between vitamin D levels and disease activity was found.