CAC scores may predict future CVD events in patients with type 1 diabetes

Matthew J. Budoff

CHICAGO — Coronary artery calcium scores may be effective in predicting future CVD events in patients with type 1 diabetes, with scores over 100 associated with a significantly increased risk, according to findings presented at the American Heart Association Scientific Sessions.

“We know a lot less about cardiovascular risk and cardiovascular risk factors in type 1 diabetes compared to type 2 diabetes,” Matthew J. Budoff, MD, of the UCLA School of Medicine, Los Angeles Biomedical Research Institute, said during a presentation. “We hear more and more about these new therapies that are being applied to type 2 diabetes – every day there’s a big breaking clinical trial. We really have less information still about type 1. We know that there is increased risk of cardiovascular complications. Coronary artery calcium score is exceptionally well validated in the setting of diabetes. In the last guidelines that addressed diabetes specifically, it was [a Class] IIa recommendation to do calcium scoring in type 2 diabetes with no recommendations given for type 1. The reason is we really didn’t have outcome data for type 1 diabetes until this study.”

To examine the relationship between coronary artery calcium (CAC) scores and subsequent CVD and major adverse cardiovascular events (MACE), researchers used computed tomography to measure CAC scores in 1,205 patients who were participating in the Diabetes Control and Complications Trial (DCCT) and the Epidemiology of Diabetes Interventions and Complications (EDIC) study between 2001 and 2003 (mean age, 42.8 years; 1,156 at risk of an initial CVD event; 1,187 at risk of an initial MACE event).

CAC scores were measured in Agatston units and categorized as 0, >0 to 100, >100 to 300 or >300.

Researchers looked at CAC scores in relation to the time of the first subsequent CVD or MACE event over 10 to 13 years. Mean follow-up time was 11 years. During this time, 105 participants had an initial CVD event (8.5 per 1,000 patient years) and 51 participants had an initial MACE event (3.9 per 1,000 patient years).

Researchers found that among the 817 participants with a CAC score of 0, the CVD event rate was low (5.6 per 1,000 patient years).

After adjusting for computed tomography scanning site, gender and age, it was determined that CAC scores >100 were associated with an increased risk of CVD and MACE events with approximately 20% of participants with CAC scores >100 suffering a CV event and approximately 30% of participants with CAC scores >300 suffering a CV event during follow-up.

“I would argue that this data plays out very similarly to the general population where a high calcium score is a high risk [for CV events],” Budoff said. “In asymptomatic patients, consider measuring coronary artery calcium. These patients were very low risk with a score of 0 – as the score [goes] above 100, advocate for initiating step therapy.” – by Melissa J. Webb

Reference:

Budoff MJ, et al. 166. The Association of Coronary Artery Calcification (CAC) With Subsequent Cardiovascular Disease (CVD) in DCCT/EDIC. Presented at: American Heart Association Scientific Sessions; Nov. 10-12, 2018; Chicago.

Disclosure:

Budoff reports receiving research grants from NIH and General Electric. Another author reports being a consultant for Reata Pharmaceutical and receiving grant money from Boehringer-Ingelheim Pharmaceutical and Gan & Lee Pharmaceutical.