Routine CT Angiography Screening Unnecessary for Diabetes

Routine advanced coronary CT angiography (CCTA) screening in patients with diabetes does not result in significant long-term reduction in death, heart attack, or hospitalization, according to a study published in JAMA.

Researchers from Intermountain Medical Center Heart Institute in Murray, Utah performed a randomized trial to determine if this type of routine screening could guide preventative therapy for coronary artery disease (CAD) among patients with diabetes.

"Many diabetics die from heart disease before they ever have any typical heart attack-related symptoms," lead researcher Brent Muhlestein, MD, director of cardiovascular research at the center, said in a release. "The question was whether screening for the presence of silent heart disease in these patients would be helpful.”

A total of 900 participants who had diabetes mellitus (DM) for three years or less participated in the trial. They were prospectively followed from January 2008 to August 2014. Male participants were 50 years or younger, females were 55 years or younger. None had symptoms of CAD at the start of the study. The participants who were randomly assigned to be assessed by CCTA were managed by their physicians, according to pre-specified trial recommendations. Participants in the control group received standard medical therapy.[[{"type":"media","view_mode":"media_crop","fid":"29551","attributes":{"alt":"Brent Muhlestein, MD, lead researcher","class":"media-image media-image-right","id":"media_crop_6878364149514","media_crop_h":"0","media_crop_image_style":"-1","media_crop_instance":"3060","media_crop_rotate":"0","media_crop_scale_h":"0","media_crop_scale_w":"0","media_crop_w":"0","media_crop_x":"0","media_crop_y":"0","style":"border-width: 0px; border-style: solid; margin: 1px; float: right;","title":"Brent Muhlestein, MD, lead researcher","typeof":"foaf:Image"}}]]

The results showed that after four years of follow-up, the occurrence of deaths, MIs, and episodes of unstable angina did not differ significantly between those who were screened (6.2%), and those who were not (7.6%). There were only a modest number of revascularization procedures and an increase in the use of cholesterol-lowering statin drugs as a result of the screening.

"This non-invasive imaging technology that we have is incredibly accurate, however, it does involve additional expense and some radiation exposure," Muhlestein concluded in the release. "Previous studies have shown that CCTA screening is nearly as good as standard invasive heart catheterization in defining coronary arteries. Because of this, we hoped this new technology would help us identify heart disease in high-risk patients who don't have symptoms, and thereby allow us to better care for them. However, it turned out that the excellent standard of care offered to diabetic patients is just as effective."