Danish study suggests starting CVD screening before age 70

Results point to a screening target age below 70 years, for a substantial reduction of combined endpoints of death, stroke, or myocardial infarction.

The age group 65–69 years may benefit from screening

The DANCAVAS study (ISRCTN12157806) was a population-based, randomised-controlled screening trial attempting to address the significant increase in the average life expectancy and incipient CVD, explained Prof. Axel Cosmus Pyndt Diederichsen (Odense University Hospital, Denmark) in his presentation1. The results were simultaneously published in the New England Journal of Medicine2. The trial aimed to evaluate the health benefits and cost effectiveness of using non-contrast CT scans to measure coronary artery calcification and identify aortic/iliac aneurysms and measurements of the ankle brachial blood pressure index as part of a multifocal screening and intervention program for CVD in men aged 65–74.

Between September 2014 and September 2017, 46,526 Danish men aged 65–74 years living in particular municipalities of Denmark were included; no exclusion criteria were applied. One third (n=16,736) of the men were randomised to receive an invitation to the screening, while the remaining two thirds (n=29,790) of the men acted as clinical controls. The primary endpoint was all-cause mortality. Key secondary endpoints were stroke, myocardial infarction, amputation due to vascular disease, aortic dissection, and aortic rupture. The researchers powered the trial with the assumption that the attendance to screening would be 70%.

However, the attendance to screening was only 63%, and the primary endpoint was not met. With a median follow-up of 5.6 years, 12.6% men in the screening group and 13.1% men in the control group had died, corresponding to a non-significant 5% relative risk reduction (HR 0.95; 95% CI 0.90–1.00; P=0.062). To prevent a single death, the number needed to invite to screening was 155.

Still, subgroup analyses did indicate that a slightly younger age group (65–69 years) may benefit from screening; while there was no difference among men aged 70 years and older (HR 1.01; 95% CI 0.94–1.09; P=0.747), an 11% decreased risk in those aged 65–69 years was observed (HR 0.89; 95% CI 0.83–0.96; P=0.004).

A substantial reduction of events with comprehensive CV screening

Secondary endpoint results varied. With regard to stroke, the screening seemed to help; 7.0% men in the screening group experienced a stroke compared with 7.5% in the control group (HR 0.93; 95% CI 0.86–0.99; P=0.035). Conversely, there were no differences between the 2 groups in aortic dissection (HR 0.95; 95% CI 0.61–1.49; P=0.827), aortic rupture (HR 0.81; 95% CI 0.49–1.35; P=0.420), amputation due to vascular disease (HR 1.05; 95% CI 0.80–1.38; P=0.711), or myocardial infarction (HR 0.91; 95% CI 0.81–1.03; P=0.134).

Not surprisingly, the group who had attended screening were prescribed more lipid-lowering agents (20.7% vs 9.0%; HR 2.54; 95% CI 2.42–2.67; P<0.001), and antithrombotic agents (22.9% vs 8.3%; HR 3.12; 95% CI 2.97–3.28; P<0.001). Likewise, elective aortic aneurysm repair was more common in the screening group compared with the control group (1.5% vs 1.2%; HR 1.29; 95% CI 1.07–1.48; P=0.006). However, there were no differences in prescription of anticoagulants, antihypertensive medications, or therapies to treat diabetes.

Prof. Diederichsen concluded optimistically: “We observed a substantial reduction in the combined endpoint of death, stroke, or myocardial infarction in elderly men by comprehensive cardiovascular screening. Our results point quite firmly at a screening target age below 70 years.”

References
  1. Diederichsen ACP, et al. DANCAVAS - Screening and intervention to prevent cardiovascular disease. Hot Line Session 2, ESC Congress 2022, Barcelona, Spain, 26–29 August.
  2. Lindholt JS, et al. N Engl J Med. 2022 Aug 27. doi: 10.1056/NEJMoa2208681.