Background and aims To study the association between serum 25-Hydroxyvitamin D3 levels and clinical manifestation, disease activity, and disease damage of systemic lupus erythematosus (SLE).

Methods This was a retrospective cross sectional study of SLE patients seen between 1996 until 2015. Patients were grouped according to the Vitamin D3 levels : group 1 (<25 nmol/L : deficiency), group 2 (25–75 nmol/L : insufficiency) and group 3 (>75 nmol/L : adequate). Assessment of disease activity was done using Systemic Lupus Erythematosus Disease Activity Index Selena Modification (SLEDAI) while Systemic Lupus International Collaborating Clinics (SLICC) was use for disease damage.

Results A total of 42 patients had their serum 25-Hydroxyvitamin D3 levels taken at one point of their visit. Majority were females (n=41). Mean age was 37.2 years (SD ±13.13) and mean duration of illness 9.5 years (SD ±5.7). The proportion of patients with 25-Hydroxyvitamin D3 level group 1 was 31%, group 2 was 61.9% and group 3 was 7.1% respectively. Main clinical manifestations were haematological 71.1%, arthritis 68.9%, malar rash 53.3%. SLEDAI mild activity (0-3) 90.5%, moderate activity (4-8) was 4.8% and severe activity (>8) was 4.8%. SLICC showed 78.6% had no damage and 21.4% with damage. Test of association using ANOVA, did not show any significance between Vitamin D3 level and SLEDAI, SLICC and clinical manifestations were observed among the group.

Conclusions Vitamin D insufficiency and deficiency was common in our SLE cohort.However, we did not find significant association between vitamin D deficiency and disease activity, damage or clinical manifestations. The study limitation includes small number of patients and retrospective design.