Randomized Preventive Vascular Screening Trial of 65-74 Year Old Men in the Central Region of Denmark

Overview

Well-documented health benefits may be achieved through prophylactic screening for cardiovascular disease. The advantages are fewer premature deaths and a reduction in the number of hospital admissions and amputations. Furthermore, hospitals will benefit from the derived reduction in the pressure on surgery and intensive care capacities at vascular surgery departments. It therefore seems extremely relevant to offer joint screening for abdominal aortic aneurysm, peripheral arterial disease and hypertension, even if the benefit and costs of such a measure are not currently known. Consequently, the primary objective of the study is to establish the effect and cost-efficiency of a joint circulation screening programme for 40,000 men aged 65-74 years in a randomised, clinically controlled study. The project manager will train six nurses to measure ABI and perform ultrasound scans of the aorta. The nurses form three teams which will each be equipped with a portable Doppler, blood pressure cuff and portable ultrasound scanner. Each team will operate from the hospitals in the Region. Civil registration number (in Danish: CPR), name and address information will be supplied by the Clinical Epidemiological Department (CED), which will also perform the randomisation in groups of approx. 1,000 to avoid too long a period from data extraction to invitation. Half of the randomised subjects will be invited to participate in a circulation examination focused on PAD, AAA and hypertension, while the other half will be controls Men with positive findings are informed and proper preventive actions is taken. Annual controls are offered, and AAA exceeding 5.5 cm in diameter is offered operation. The primary efficiency variables are death, cardiovascular death and AAA-death. The secondary efficiency variables are hospital services related to cardiovascular conditions and costs for such services in accordance with current DRG rates. The entire population, the controls as well as the screening group, will be monitored for a period of 10 years. Information concerning deaths, including date of death, is obtained from the Civil Registration System, information on visits to outpatient clinics and hospital admissions caused by cardiovascular conditions including amputations is obtained from the National Patient Registry. From the Danish Causes of Death Registry information on cause of death is collected. The information is classified with regards to cause; AAA or cardiovascular. The cardiovascular interventions are identified in the vascular surgery database (Karbasen). Major follow-up is performed at 3, 5 and 10 years. A steering and data validation group will be formed including the project manager and a representative from the Clinical Epidemiology Department. Furthermore, a vascular surgeon from each of the two affected departments in the region will participate. Total mortality, cardiovascular and AAA-related mortality and initial cardiovascular hospital service are compared for the two groups using Cox proportional hazards-regression analysis which facilitates description of the risk ratio. The cost-efficiency calculation will be adjusted for quality of life.