Comprehensive image-based cardiovascular screening in men aged 65-74 years did not significantly reduce all-cause mortality in a new Danish study, although there were strong suggestions of benefit in some cardiovascular endpoints in the whole group and also in mortality in those aged younger than 70.
The DANCAVAS study was presented at the annual congress of the European Society of Cardiology, being held in Barcelona. It was also simultaneously published online in The New England Journal of Medicine.
“I do believe there is something in this study,” lead investigator Axel Diederichsen, PhD, Odense University Hospital, Denmark, told this news organization.
“We can decrease all-cause mortality by screening in men younger than 70. That’s amazing, I think. And in the entire group the composite endpoint of all-cause mortality/MI/stroke was significantly reduced by 7%.”
He pointed out that only 63% of the screening group actually attended the tests. “So that 63% had to account for the difference of 100% of the screening group, with an all-cause mortality endpoint. That is very ambitious. But even so, we were very close to meeting the all-cause mortality primary endpoint.”
Dr. Diederichsen believes the data could support such cardiovascular screening in men younger than 70. “In Denmark, I think this would be feasible, and our study suggests it would be cost effective compared to cancer screening,” he said.
Noting that Denmark has a relatively healthy population with good routine care, he added: “In other countries where it can be more difficult to access care or where cardiovascular health is not so good, such a screening program would probably have a greater effect.”
The population-based DANCAVAS trial randomly assigned 46,611 Danish men aged 65-74 years in a 1:2 ratio to undergo screening (invited group) or not to undergo screening (control group) for subclinical cardiovascular disease.
Screening included non-contrast electrocardiography-gated CT to determine the coronary-artery calcium score and to detect aneurysms and atrial fibrillation; ankle–brachial blood-pressure measurements to detect peripheral artery disease and hypertension; and a blood sample to detect diabetes and hypercholesterolemia. Of the 16,736 men who were invited to the screening group, 10,471 (62.6%) actually attended for the screening.
In intention-to-treat analyses, after a median follow-up of 5.6 years, the primary endpoint (all cause death) had occurred in 2,106 men (12.6%) in the invited group and 3,915 men (13.1%) in the control group (hazard ratio, 0.95; 95% confidence interval, 0.90-1.00; P = .06).
The hazard ratio for stroke in the invited group, compared with the control group, was 0.93 (95% confidence interval, 0.86-0.99); for MI, 0.91 (95% CI, 0.81-1.03); for aortic dissection, 0.95 (95% CI, 0.61-1.49); and for aortic rupture, 0.81 (95% CI, 0.49-1.35).
The post-hoc composite endpoint of all-cause mortality/stroke/MI was reduced by 7%, with a hazard ratio of 0.93 (95% CI, 0.89-0.97).
There were no significant between-group differences in safety outcomes.
Subgroup analysis showed that the primary outcome of all-cause mortality was significantly reduced in men invited to screening who were aged 65-69 years (HR, 0.89; 95% CI, 0.83-0.96), with no effect in men aged 70-74.
Other findings showed that in the group invited to screening, there was a large increase in use of antiplatelet medication (HR, 3.12) and in lipid lowering agents (HR, 2.54) but no difference in use of anticoagulants, antihypertensives, and diabetes drugs or in coronary or aortic revascularization.
In terms of cost-effectiveness, the total additional health care costs were €207 ($206 U.S.) per person in the invited group, which included the screening, medication, and all physician and hospital visits.
The quality-adjusted life-year (QALY) gained per person was 0.023, with an incremental cost-effectiveness ratio of €9,075 ($9,043) per QALY in the whole cohort and €3,860 ($3,846) in the men aged 65-69.
Dr. Diederichsen said these figures compared favorably to cancer screening, with breast cancer screening having a cost-effectiveness ratio of €22,000 ($21,923) per QALY.
“This study is a step in the right direction,” Dr. Diederichsen said in an interview. But governments will have to decide if they want to spend public money on this type of screening. I would like this to happen. We can make a case for it with this data.”
He said the study had also collected some data on younger men – aged 60-64 – and in a small group of women, which has not been analyzed yet. “We would like to look at this to help us formulate recommendations,” he added.