HbA1c increase is associated with higher coronary and peripheral atherosclerotic burden in non diabetic patients

Background and aims Prediabetes is associated with an increased risk of developing diabetes and cardiovascular disease. Our objective was to examine the cardiovascular (CV) risk profile of non-diabetic patients with and without prediabetes according to HbA1c, using macroangiopathic imaging biomarkers. Methods Our population consisted of 272 non diabetic patients aged between 40 and 70 years, with a normal fasting plasma glucose (FPG <5.6 mmol/L) and at least 1 CV risk factor. Exclusion criteria were prior history of CV disease or clinical evidence of advanced renal disease. Prediabetes was defined as an HbA1c value of 5.7–6.4%. Coronary artery calcium (CAC) score as well as mean common carotid intima media thickness (IMT) and plaque presence were assessed using consensus criteria. Results CAC score was higher in the prediabetes group compared to non-prediabetic subjects (131.7 ± 295.6 vs. 62.4 ± 178.8 AU, p < 0.001). Prediabetic subjects had higher mean IMT than non-exposed subjects (0.77 ± 0.14 vs. 0.61 ± 0.15 mm, p < 0.001). The proportion of prediabetic patients with CAC = 0 was significantly lower compared to non-exposed subjects (35% vs. 63%, p < 0.01). In contrast, the proportion of patients with a CAC >400 was significantly higher in the prediabetes group (10% vs. 3%, p < 0.05). Moreover, carotid plaques were significantly more present in patients with prediabetes than in the normoglycemic subjects (p < 0.01). In a multiple linear regression, IMT was associated with HbA1c continuous levels (p < 0.001). In addition, logistic regression showed that higher HbA1c levels were associated with CAC and carotid plaques presence (p for trend for all < 0.001). Conclusions Among patients with normal fasting glucose, HbA1c increase is associated with higher coronary and peripheral atherosclerotic burden in non-diabetic patients.