(HealthDay News) — For patients with type 2 diabetes, hemoglobin A1c (HbA1c) is not significantly associated with cardiovascular events, regardless of clinical manifestation of vascular disease, according to a study published online in Diabetes Care.

Guido Kranenburg, from the University Medical Center Utrecht in the Netherlands, and colleagues examined the correlation between glycemic control and new cardiovascular events and mortality in 1,687 patients with type 2 diabetes, with and without cardiovascular disease, who were followed for a median of 6.1 years.

The researchers found that the hazard ratio (HR) of the correlation between HbA1c level and cardiovascular events was 1.06 in all patients (95% confidence interval [CI], 0.97 to 1.17). There was an increased risk of a cardiovascular event in association with a 1% higher HbA1c level for patients with type 2 diabetes without vascular disease (HR, 1.27; 95% CI, 1.06 to 1.51), but not in those with vascular disease (HR, 1.03; 95% CI, 0.93 to 1.15) (P for interaction = 0.195). Patients with vascular disease had an increased risk of death with a 1% higher HbA1c level (HR, 1.16; 95% CI, 1.06 to 1.28); the risk was not significant for patients without vascular disease (HR, 1.13; 95% CI, 0.97 to 1.31).

“In patients with type 2 diabetes, there is a modest, but not statistically significant, relation between HbA1c level and cardiovascular events, and, as there was no statistically significant interaction, this relation was not different for patients with or without clinical manifestation of vascular disease,” the authors conclude.


  1. Kranenburg, G; van der Graaf, Y; van der Leeuw, J; et al. Diabetes Care, published online before print August 25, 2015; doi: 10.2337/dc15-0493.