Can good blood glucose control stop the stiffening of blood vessels in patients with diabetes?

The aim of this study was to investigate if optimal blood glucose control reduces the stiffening (calcification) of the arteries of the heart in patients with diabetes. The main finding of the study was that optimal blood sugar control stopped the calcification of the arteries of the heart.

Calcifications appear when calcium gets deposited into blood vessels. When this happens in the blood vessels of the heart (coronary arteries) become stiff. This means they cannot widen enough to deliver more oxygen to the heart when needed. Therefore, calcification can result in future heart attacks and strokes.

Patients with diabetes are at a much higher risk of heart and blood vessel disease. Therefore, it is important that they have good blood glucose control. This is measured by HbA1c (blood test measuring an average blood sugar over the past three months). Optimal blood glucose control is HbA1c below 7%.

 It is unknown if good blood glucose control in diabetes can reduce coronary artery calcification (CAC).

This study included 1,637 patients with diabetes that had no past heart disease or strokes. Patients underwent CAC testing to see how calcified their arteries were. Their change in CAC was measured and compared to their blood glucose control. Patients were followed for an average of 3 years.

Patients with optimal blood glucose control had less worsening of CAC over time (45.4%) compared to those without optimal blood glucose control (51.7%). Overall, patients with optimal blood glucose control had 25% less risk of their CAC worsening.

Optimal blood glucose control significantly reduced the risk of CAC in patients less than 65 years old by 21.2% and in smokers by 23.1%. In patients with high cholesterol, this risk was reduced by 20.9% and in those with normal weight by 35%. 

The authors concluded that optimal blood glucose control in patients with diabetes can reduce the risk of worsening calcification of the heart arteries.

This study looked back at the medical records of patients. Also, the authors did not take into account the medications for diabetes, high blood pressure or high cholesterol used by the patients. This might have influenced the results.