Albumin to globulin ratio (AGR) in systemic lupus erythematosus: correlation with disease activity

Objective To investigate the role of albumin-to-globulin ratio (AGR) in systemic lupus erythematosus (SLE) and its relationship with disease activity. Methods This retrospective study consecutively selected patients with SLE and healthy controls. Patients were divided into three groups according to the SLE Disease Activity Index 2000 (SLEDAI-2K): group 1 (mild disease activity, SLEDAI-2K <= 6), group 2 (moderate disease activity, SLEDAI-2K 7-12) and group 3 (severe disease activity, SLEDAI-2K > 12). Predictors of SLE disease activity were analysed by ordinal logistical regression. Results A total of 101 Chinese patients with SLE and 75 healthy Chinese controls were included. Patients with SLE had lower AGR values than healthy individuals, and group 3 patients with SLE displayed lower AGR values than those in group 1, but similar values to group 2. AGR was inversely correlated with SLEDAI-2K (r = -0.543). Ordinal logistic regression analysis showed that lower AGR (beta = -1.319) and lower complement C4 (beta = -1.073) were independent risk factors for SLE disease activity. Conclusions AGR was decreased in patients with SLE and may be utilized as a useful inflammatory biomarker for monitoring SLE disease activity.