Abstract
BACKGROUND: Coronary artery disease (CAD) is a significant complication of type 2 diabetes mellitus (T2DM). The relationship between long-term glycemic variability (GV) and CAD severity remains uncertain. This study aimed to investigate the association between long-term GV and the extent of CAD in individuals with T2DM. MATERIALS AND METHODS: This retrospective cohort study included patients with T2DM who underwent coronary angiography. Mean-HbA1c was calculated for each patient. GV was assessed by measuring the standard deviation (SD) and coefficient of variation (CV) of HbA1c measurements. The severity of coronary artery lesions was evaluated using the SYNTAX scoring system. Linear regression analyses were performed to assess the differences in SYNTAX scores among different mean-HbA1c groups, as well as SD-HbA1c and CV-HbA1c quartiles. RESULTS: A total of 115 diabetic patients were included in the study. The mean-HbA1c cutoff value of 7.5 was derived from the receiver-operating characteristic curve. Fifty-six patients had a mean-HbA1c of 7.5 or lower, whereas 59 patients had a mean-HbA1c above 7.5. Univariate analysis revealed that patients with mean-HbA1c above 7.5 had significantly higher SYNTAX scores compared to those with lower mean-HbA1c levels (12.79 vs. 7.33, P < 0.05). There was no significant correlation observed between SD-HbA1c, CV-HbA1c, and SYNTAX scores in both univariate and multivariate analyses. CONCLUSION: This study suggests that higher mean-HbA1c levels are associated with increased severity of CAD in individuals with T2DM. However, long-term HbA1c variability, as measured by SD-HbA1c and CV-HbA1c, does not appear to have a significant impact on the severity of CAD.