The proportion of patients with diabetes undergoing coronary artery bypass grafting (CABG) has increased 5-fold in the past 40 years, indicate study findings published in the Journal of Thoracic and Cardiovascular Surgery.
Driven largely by the obesity epidemic, the incidence of diabetes has increased dramatically during the same time period. In 2010, approximately 285 million people worldwide had diabetes — a number that has more than doubled in the past 3 decades — as well as 29.1 million people in the United States alone (9.3% of the population).
Study researcher Sajjad Raza, MD, of the Cleveland Clinic in Ohio, and colleagues observed outcomes among more than 57,000 patients who underwent CABG in a 4-decade period. They specifically compared outcomes among patients with diabetes (either treated with insulin or with oral hypoglycemic agents) vs those without the disorder. In the 1970s, 7% of patients who underwent CABG had diabetes compared with 37% in the 2000s, the researchers noted.
The study findings confirmed what most clinicians already know: that CABG outcomes are worse in patients with diabetes vs those without the disease and include higher in-hospital (2% vs 1.3%) and long-term mortality at 5 (84% vs 80%), 10 (66% vs 56%), and 20 years (32% vs 20%).
Patients with diabetes also had a significantly higher incidence of complications, including deep sternal wound infections (2.3% vs 1.2%), stroke (2.2% vs 1.4%), renal failure (4% vs 1.3%), and prolonged postoperative hospital stay (9.6% vs 6%). Their hospital costs were also 9% greater, the researchers found.
A growing threat to the US economy, diabetes-related medical expenses are nearly 2.3 times higher than the medical expenses of patients without diabetes. This economic burden is expected to increase as the number of diabetes cases rises. Addressing this will depend largely on prevention efforts, the study researchers suggested.
“In people with prediabetes, cost-effective lifestyle interventions have been shown to have a positive effect on preventing development of the disease,” the researchers wrote. “In people with diagnosed diabetes, controlling blood sugar and cardiovascular disease risk factors, such as hypertension and hypercholesterolemia, has been shown to help reduce cardiovascular events.”