Association Between Glycated Hemoglobin and Coronary Artery Calcification in Middle-Aged and Elderly Chinese Checkup Populations.

Background: Previous studies have established that coronary artery calcification (CAC) is a robust predictor of adverse cardiovascular events.

Objectives: To examine the association between levels of glycated hemoglobin (HbA1c), an indicator of long-term blood glucose levels, and CAC in middle-aged and elderly Chinese populations undergoing routine health screenings.

Methods: A cross-sectional study was conducted on 8,955 Chinese adults over 40 years of age who underwent physical examinations in the Department of Health Medicine at our hospital from January 2022 to July 2023. The odds ratios (ORs) of CAC in relation to HbA1c were determined using multiple logistic regression analysis, both as a continuous and categorical variable. Furthermore, dose-response relationships between HbA1c levels and CAC were visualized using restricted cubic spline models.

Results: Compared to the group with HbA1c lower than 5.7%, individuals in the groups with HbA1c of 5.7% to 6.4% and ≥ 6.5% exhibited an elevated prevalence of CAC (P for trend < 0.0001). Multivariable logistic regression showed that each 1% increase in HbA1c was associated with a 24% increased risk of CAC (OR = 1.24, 95% CI: 1.03-1.48, P = 0.02). Compared with the group with HbA1c lower than 5.7%, the groups with HbA1c at 5.7% - 6.4% and HbA1c ≥ 6.5% were associated with a 28% (OR = 1.28, 95% CI: 1.07 - 1.52) and 116% (OR = 2.16, 95% CI: 1.48 - 3.16) (P for trend < 0.0001) increased risk of CAC, respectively. Restricted cubic spline analyses showed a non-linear association between HbA1c and CAC (P for nonlinearity < 0.0001). At higher levels of HbA1c exposure (> 5.7%), the exposure dose-response curves appeared upward-sloping. Subgroup analyses showed that the association between HbA1c and CAC was more pronounced in those aged less than 60 years, with normal weight and blood pressure less than 135/85 mmHg, although none of the interactions between HbA1c and subgroups were statistically significant.

Conclusions: This study indicated that higher HbA1c levels are associated with a greater likelihood of CAC in the middle-aged and elderly Chinese checkup population.