Patients with stable ischemic heart disease and diabetes have improved survival when risk factors such as lifestyle behaviors and glycated hemoglobin A1c (HbA1c) level are controlled, according to study results published in The Journal of the American College of Cardiology.
Researchers followed 690 people with high-risk stable ischemic heart disease and diabetes to determine whether controlling various risk factors affected survival rates. The patients had been randomly assigned during a previous trial to receive optimal medical therapy plus percutaneous coronary intervention or optimal medical therapy alone.
The researchers’ primary outcome was mortality beyond 1 year of treatment. Prespecified risk factor goals included measures of systolic blood pressure, low-density lipoprotein cholesterol, smoking, physical activity, diet adherence, body mass index, and HbA1c. Of the total population, 86% had recorded data for all 7 risk factors at baseline and after 1 year.
Participants were followed for an average of 8.0 years after treatment initiation. In that time, 186 patients died (31.4 % overall; 4.5% each year). The researchers found that a higher probability of survival was associated with having a greater number of risk factors controlled at 1 year (P =.002).
Furthermore, controlling ≥3 factors predicted a hazard ratio of 0.35 for mortality, and control of 3 to 7 factors predicted progressively lower mortality rates (hazard ratio with control of 6 or 7 factors, 0.13). Only 10.3% of participants were able to control 6 or 7 risk factors. On average, each additional goal achieved resulted in a 17% decrease in risk for death (hazard ratio, 0.83; P <.001).
According to multivariate analysis, the most significant predictors of greater survival odds were no smoking, regular physical activity, dietary adherence, and achievement of HbA1c levels <7%.
Limitations to this study included potential confounding factors.
“In patients with both [stable ischemic heart disease and diabetes], comprehensive risk factor management is an important strategy that improves survival over the long term,” the researchers said, highlighting “an urgent need to develop better strategies to support the attainment of secondary prevention goals in patients with [stable ischemic heart disease and diabetes].”
Mancini GBJ, Maron DJ, Hartigan PM, et al. Lifestyle, glycosylated hemoglobin A1c, and survival among patients with stable ischemic heart disease and diabetes. J Am Coll Cardiol. 2019;73(16):2049-2058.