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.