In a Hot Line session yesterday, Professor Axel Diederichsen (Odense University Hospital - Odense, Denmark) presented results from the Danish Cardiovascular Screening (DANCAVAS) trial, which was designed to evaluate the benefits of a multifocal screening and intervention programme for CVD in men aged 65 to 74 years.
Prof. Diederichsen says, “More than half of CVD is avoidable, meaning that successful prevention has a huge potential to improve public health. DANCAVAS investigated whether screening, including imaging, for seven CV conditions, and treatment if indicated, could prevent death and CVD.”
The pragmatic, population-based trial identified all men aged 65 to 74 years from 15 regions of Denmark and randomised participants 1:2 to screening/intervention (n=16,736) or to the usual Danish practice of no screening (n=29,790). Screening comprised cardiac and truncal non-contrast computed tomography to detect coronary artery calcification above the sex- and age-specific median, aortic and iliac aneurysms, and atrial fibrillation, along with measurement of brachial and ankle blood pressure in both arms and legs, and assessment of cholesterol and HbA1c levels. In case of abnormal findings, prophylactic treatments, including medication and aortic surgery, were offered. Information on medication, surgery, CVD and death after 5 years of follow up was obtained from national registries. The average age of participants was 68.8 years.
At a median follow up of 5.6 years, there was a non-significant 5% relative risk reduction in the primary endpoint of all-cause mortality: 12.6% of men in the screening/intervention group and 13.1% in the control group died (hazard ratio [HR] 0.95; 95% CI 0.90 to 1.00; p=0.062). The number needed to invite to screening to prevent one death was 155.
Although there was no difference in mortality rates between the groups in men aged 70 years and older (HR 1.01; 95% CI 0.94 to 1.09; p=0.747), screening/intervention was associated with an 11% reduction in mortality risk in men aged 65 to 69 years (HR 0.89; 95% CI 0.83 to 0.96; p=0.004). A post-hoc analysis revealed that there was a screening-associated reduction in the composite endpoint of death, stroke or myocardial infarction (MI) of 7% in the overall population (p=0.016) and this rose to 11% among men aged 65 to 69 years (p=0.007).
Regarding secondary endpoints, 7.0% of men in the screening/intervention group had a stroke compared with 7.5% in the control group (HR 0.93; 95% CI 0.86 to 0.99; p=0.035). There were no differences between the two groups in MI (HR 0.91; 95% CI 0.81 to 1.03; p=0.134), amputation due to vascular disease (HR 1.05; 95% CI 0.80 to 1.38; p=0.711), aortic dissection (HR 0.95; 95% CI 0.61 to 1.49; p=0.827), or aortic rupture (HR 0.81; 95% CI 0.49 to 1.35; p=0.420).
There were more prescriptions for prophylactic antithrombotic agents (22.9% versus 8.3%; HR 3.12; 95% CI 2.97 to 3.28; p<0.001) and lipid-lowering agents (20.7% versus 9.0%; HR 2.54; 95% CI 2.42 to 2.67; p<0.001) in the screening/intervention group compared with the control group. However, prescriptions for anticoagulants, antihypertensives or antidiabetic medication were not different between groups. Elective aortic aneurysm repair was more common in the screening/intervention group compared with the control group (1.5% versus 1.2%; HR 1.29; 95% CI 1.07 to 1.48; p=0.006).
Commenting on the findings, Prof. Diederichsen says: “We observed a substantial reduction in the combined endpoint of death, stroke or MI in elderly men by comprehensive CV screening. Our results point quite firmly at a screening target age below 70 years.”