Hemoglobin A1c, Not Glycated Albumin, Can Independently Reflect the Ankylosing Spondylitis Disease Activity Score

Abstract

Objective This study examined whether glycated hemoglobin (HbA1c) and glycated albumin (GA) are well correlated with the Ankylosing Spondylitis Disease Activity Score (ASDAS)-erythrocyte sedimentation rate (ESR), and ASDAS-C-reactive protein (CRP) in AS patients without medical conditions affecting the glycated protein levels.

Methods The data of 76 patients with AS were analyzed. Univariate and multivariate analyses of the variables associated with ASDAS-ESR and ASDAS-CRP were performed using a linear regression test. The patients were divided into active and inactive AS groups based on an ASDAS-CRP of 2.1, and the variables between the two groups were compared.

Results ASDAS-ESR did not correlated with either HbA1c or GA. ASDAS-CRP was positively correlated with HbA1c (r=0.315, p=0.006) and the white blood cell (r=0.288, p=0.012), and inversely correlated with hemoglobin (r=−0.241, p=0.036) and serum albumin (r=−0.262, p=0.022), but not GA. Multivariate analysis revealed HbA1c and white blood cell to be significantly correlated with ASDAS-CRP (β=0.234, p=0.033 and β=0.265, p=0.017). The mean HbA1c, not GA, of the active group was significantly higher than that of the inactive group (p=0.020). In addition, the optimal cut-off value of HbA1c was set to 5.6, and the patients with HbA1c ≥5.6 were found to have a 3.3 times higher risk of active AS than those without.

Conclusion HbA1c was significantly correlated with ASDAS-CRP, and could be a useful marker to reflect ASDAS-CRP in AS patients without medical conditions affecting the glycated protein levels.