The Danish Cardiovascular Screening Trial (DANCAVAS): study protocol for a randomized controlled trial.

BACKGROUND

The significant increase in the average life expectancy has increased the societal challenge of managing serious age-related diseases, especially cancer and cardiovascular diseases. A routine check by a general practitioner is not sufficient to detect incipient cardiovascular disease.

DESIGN

Population-based randomized clinically controlled screening trial.

PARTICIPANTS

45,000 Danish men aged 65-74 years living on the Island of Funen, or in the surrounding communities of Vejle and Silkeborg. No exclusion criteria are used.

INTERVENTIONS

One-third will be invited to cardiovascular seven-faceted screening examinations at one of four locations. The screening will include: (1) low-dose non-contrast CT scan to detect coronary artery calcification and aortic/iliac aneurysms, (2) brachial and ankle blood pressure index to detect peripheral arterial disease and hypertension, (3) a telemetric assessment of the heart rhythm, and (4) a measurement of the cholesterol and plasma glucose levels. Up-to-date cardiovascular preventive treatment is recommended in case of positive findings.

OBJECTIVE

To investigate whether advanced cardiovascular screening will prevent death and cardiovascular events, and whether the possible health benefits are cost effective.

OUTCOME

Registry-based follow-up on all cause death (primary outcome), and costs after 3, 5 and 10 years (secondary outcome).

RANDOMIZATION

Each of the 45,000 individuals is, by EPIDATA, given a random number from 1-100. Those numbered 67+ will be offered screening; the others will act as a control group.

BLINDING

Only those randomized to the screening will be invited to the examination;the remaining participants will not. Numbers randomized: A total of 45,000 men will be randomized 1:2. Recruitment: Enrollment started October 2014.

OUTCOME

A 5% reduction in overall mortality (HR=0.95), with the risk for a type 1 error=5% and the risk for a type II error=80%, is expected. We expect a 2-year enrollment, a 10-year follow-up, and a median survival of 15 years among the controls. The attendance to screening is assumed to be 70%.

DISCUSSION

The primary aim of this so far stand-alone population-based, randomized trial will be to evaluate the health benefits and costeffectiveness of using non-contrast full truncus computer tomography (CT) scans (to measure coronary artery calcification (CAC) and identify aortic/iliac aneurysms) and measurements of the ankle brachial blood pressure index (ABI) as part of a multifocal screening and intervention program for CVD in men aged 65-74. Attendance rate and compliance to initiated preventive actions must be expected to become of major importance.

TRIAL REGISTRATION

Current Controlled Trials: ISRCTN12157806 (21 March 2015).