Improved glycemic control in patients with type 2 diabetes lowers the risk of adverse cardiovascular (CV) events, reported Katarina Eeg-Olofsson, MD, from the University of Gothenburg in Sweden at the 2012 ADA annual meeting.
In this study by Dr Eeg-Olofsson and colleagues, patients who reduced their mean hemoglobin (Hb) A1c levels by almost 1%—from 7.8% to 7%—had a significant 45% reduction in their risk of CV death.
In this observational study, Dr Eeg-Olofsson and colleagues evaluated the association between improved glycemic control during follow-up and the risk for coronary heart disease (CHD), CV disease (CVD), or total mortality in 18,035 patients with type 2 diabetes from the Swedish National Diabetes Register.
At baseline, participants (aged 30-75 years) were free of CVD and had an HbA1c level of 7% to 8.9%. The mean duration of diabetes since diagnosis was 8 to 10 years; the patients were followed from 2004 to 2009 (mean, 5.7 years).
The patients were divided into 2 groups based on their median change in HbA1c levels during follow-up—one group included 8923 patients whose HbA1c level had decreased by ≥0.1% from baseline to follow-up, and the second group included 9112 patients whose HbA1c level remained stable or increased.
HbA1c Levels and CVD-Associated Mortality Risk
After adjusting for covariates, the absolute risk for a death event from a CV cause was 9.9 events per 1000 person-years in patients with decreasing HbA1c levels compared with 17.8 events per 1000 person-years in patients with stable or increasing HbA1c levels.
Superior glycemic control was also associated with a significant 39% reduction in the risk for fatal and nonfatal CHD events, and a significant 37% reduction in the risk for fatal or nonfatal CVD events.
The absolute risk of a first fatal or nonfatal CHD event was 10.3 per 1000 person-years for those patients whose HbA1c levels declined versus 17.9 per 1000 person-years for those whose levels remained stable or increased. The rates for a first CV event were 15.1 per 1000 person-years and 26.1 events per 1000 person-years in the 2 groups, respectively.
The study demonstrates that targeting HbA1c level to 7% can help reduce the excess CVD risk seen in patients with diabetes, said Dr Eeg-Olofsson.