Researchers recommend CAC scanning for cardiac management
MedWire News: US researchers say that coronary artery calcium (CAC) scanning can improve cardiac management without incurring significant increases in downstream medical costs.
They found that, compared with no scanning, patients who underwent CAC scanning achieved significant improvements in their coronary artery disease (CAD) risk profiles.
Daniel Berman (Cedars-Sinai Medical Center, Los Angeles, California) and team randomly assigned 2137 individuals to either undergo CAC scanning (scan group; n=1424) or not undergo scanning (no scan group; n=713), and assessed the subsequent 4-year effect on CAD risk factors, downstream medical resource utilization, and healthcare costs.
All participants received private risk factor counseling at baseline, but those in the scan group received an additional review of their CAC images, including information on their CAC score and the associated clinical implications.
In the scan group, compared with the no scan group, there were significantly greater changes in systolic blood pressure (-7 vs -5 mmHg, respectively), serum low-density lipoprotein (LDL) cholesterol levels (-17 vs -11 mg/dl [-0.44 vs -0.28 mmol/l]), waist circumference among those with a high waist circumference at baseline (>40 inches for men and >35 inches for women; 0 vs 1 inch), and a tendency toward less weight gain among patients who were overweight at baseline (body mass index ≥25 kg/m2; 0 vs 1 lb).
Furthermore, in the no scan group, the mean Framingham Risk Score (FRS) increased by 0.7 from baseline indicating a 4-year progression of CAD risk, whereas in the scan group it remained essentially static, increasing by just 0.002.
The authors say that in the scan group, increasing baseline CAC scores were associated with a dose-response improvement in CAD risk factors.
Specifically, patients in the highest CAC score category (≥400), compared with those in the lowest category (0), had significantly greater changes in their systolic and diastolic blood pressure (-9 vs -4 and -8 vs -4 mmHg, respectively), total cholesterol (-39.5 vs -15.0 mg/dl [-1.02 vs -0.39 mmol/l]), LDL cholesterol (-29 vs -12 mg/dl [-0.75 vs -0.31 mmol/l]), triglycerides (-25 vs -8 mg/dl [-0.28 vs -0.09 mmol/l]), and weight (-3 vs 1 lb).
Overall, there were no significant differences between the two groups for downstream medical testing and procedure rates. However, Berman et al report a 25% greater reduction in medication costs and a 37% reduction in procedure costs in the normal CAC scan group (CAC score of 0), compared with the no scan group.
The group concludes in the Journal of the American College of Cardiology: "The results of our study indicate a need for future large-scale clinical trials to determine whether our findings are applicable to different patient populations and to determine whether the salutatory effect of CAC scanning on CAD risk profiles translates to reductions in adverse clinical events."
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By Nikki Withers