Elevated soluble intercellular adhesion molecule-1 levels in patients with systemic lupus erythematosus: relation to insulin resistance.

OBJECTIVE: Intracellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) are members of the immunoglobulin supergene family and play a central role in cell-to-cell and in cell-to-extracellular matrix-mediated immune responses. Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by a wide variety of immunological abnormalities. The relationship between soluble adhesion molecules and insulin resistance has been observed in different populations. However, the association of circulating levels of soluble cell adhesion molecules with insulin resistance and/or hyperinsulinemia in patients with SLE has not been extensively established.

METHODS: We evaluated the relationship of soluble ICAM-1 (sICAM-1) and VCAM-1 (sVCAM-1) to insulin resistance in 68 patients with SLE and 34 age-matched healthy controls.

RESULTS: Patients with SLE had significantly higher fasting insulin levels, homeostasis model assessment insulin resistance (HOMA-IR), HOMA beta-cell, and plasma levels of sICAM-1 and sVCAM-1 than controls. SLE patients with HOMA-IR in the top quartile had the highest plasma levels of sICAM-1. However, there was no statistical difference in plasma levels of sVCAM-1 between patients in the respective quartiles of insulin sensitivity-related variables. Plasma levels of sICAM-1, but not sVCAM-1, were significantly correlated with fasting insulin (r = 0.327, p = 0.006), HOMA-IR (r = 0.278, p = 0.022), and HOMA beta-cell (r = 0.359, p = 0.003). In addition, fasting insulin was responsible for sICAM-1 variability in patients with SLE.

CONCLUSION: The elevation of plasma levels of sICAM-1 was associated with a status of insulin resistance in patients with SLE.