Association between hemoglobin A1c and asymptomatic carotid intima-media thickness in middle-aged and elderly populations without diabetes

Background and aims Carotid atherosclerosis, including carotid artery intima-media thickness, plaques, and stenosis, is an important risk factor for stroke. However, the association between hemoglobin A 1c (HbA 1c ) and carotid intima-media thickness (cIMT) was inconsistent. The aim of this study was to explore the association between HbA 1c and the risk of increased cIMT among the Chinese population aged ≥40 years without diabetes. Methods and results A total of 3528 participants without diabetes from the China National Stroke Screen Survey program were enrolled in this study. cIMT was measured using duplex ultrasound examination. Logistic regression models were used to assess the association between HbA 1c level and the risk of increased cIMT. A total of 565 (16.0%) participants had increased cIMT. After adjustment for other potential confounding factors, higher levels of HbA 1c increased the risk of increased cIMT compared with the lowest level, and the odds ratios for quartile 2, quartile 3, and quartile 4 were 1.58, 1.67, and 1.98, respectively. Age had an interaction impact on the association between HbA 1c level and the risk of increased cIMT. Conclusion In this large-scale and cross-sectional study, high-normal HbA 1c was associated with the risk of increased asymptomatic cIMT in a rural Chinese population without diabetes, especially in individuals aged <60 years.