Lower vitamin D is associated with metabolic syndrome and insulin resistance in systemic lupus: data from an international inception cohort

Objectives Vitamin D (25(OH)D) deficiency and metabolic syndrome (MetS) may both contribute to increased cardiovascular risk in SLE. We aimed to examine the association of demographic factors, SLE phenotype, therapy and vitamin D levels with MetS and insulin resistance. Methods The Systemic Lupus International Collaborating Clinics (SLICC) enrolled patients recently diagnosed with SLE ( Results Of the 1847 patients, 1163 (63%) had vitamin D measured and 398 (34.2%) subjects were in the lowest 25(OH)D tertile. MetS was present in 286 of 860 (33%) patients whose status could be determined. Patients with lower 25(OH)D were more likely to have MetS and higher HOMA-IR. The MetS components, hypertension, hypertriglyceridemia and decreased high-density lipoprotein (HDL) were all significantly associated with lower 25(OH)D. Increased average glucocorticoid exposure was associated with higher insulin resistance. Conclusions MetS and insulin resistance are associated with lower vitamin D in patients with SLE. Further studies could determine whether vitamin D repletion confers better control of these cardiovascular risk factors and improve long-term outcomes in SLE.