Relatively High Pulmonary and Cardiovascular Mortality Rates in Screening-detected Aneurysmal Patients Without Previous Hospital Admissions

A Systematic Review and Meta-Analysis of the Incidence and Risk Factors for Major Adverse Cardiovascular Events in Patients with Unrepaired Abdominal Aortic Aneurysms

Major adverse cardiovascular events (MACE), including myocardial infarction (MI), stroke and cardiovascular death, cause substantial morbidity and mortality. This review assessed the incidence rate of MACE and the association with modifiable risk factors (diabetes, hypertension) and medication use (aspirin, statins) in patients with unrepaired abdominal aortic aneurysm (AAA). Electronic databases were searched systematically for observational studies reporting the incidence of MI, stroke or cardiovascular death in patients with unrepaired AAAs. The primary outcome was cardiovascular death reported as an incidence rate (events per 100 person-years (PY)). Fourteen studies, including 69,579 participants with a mean follow-up time of 5.4 years, were included. Meta-analysis revealed the overall incidence of cardiovascular death, MI and stroke of 2.31 per 100 PY (95% CI, 1.63-3.26; I² = 98%), 1.65 per 100 PY (95% CI, 1.01-2.69, I² = 88%) and 0.89 per 100 PY (95% CI, 0.53-1.48, I² = 87.0%), respectively. The mean rates of statin and aspirin prescriptions were 58.1% and 53.5%, respectively. In conclusion, there is a substantial incidence of MACE in patients with unrepaired AAA, but the prescription of preventative medication is suboptimal. Greater emphasis should be placed on secondary prevention in this population.

Safety of Men With Small and Medium Abdominal Aortic Aneurysms Under Surveillance in the NAAASP

BACKGROUND

Population screening for abdominal aortic aneurysm (AAA) has commenced in several countries, and has been shown to reduce AAA-related mortality by up to 50%. Most men who screen positive have an AAA <5.5 cm in diameter, the referral threshold for treatment, and are entered into an ultrasound surveillance program. This study aimed to determine the risk of ruptured AAA (rAAA) in men under surveillance.

METHODS

Men in the National Health Service AAA Screening Programme who initially had a small (3-4.4 cm) or medium (4.5-5.4 cm) AAA were followed up. The screening program's database collected data on ultrasound AAA diameter measurements, dates of referral, and loss to follow-up. Local screening programs recorded adverse outcomes, including rAAA and death. Rupture and mortality rates were calculated by initial and final known AAA diameter.

RESULTS

A total of 18 652 men were included (50 103 person-years of surveillance). Thirty-one men had rAAA during surveillance, of whom 29 died. Some 952 men died of other causes during surveillance, mainly cardiovascular complications (26.3%) and cancer (31.2%). The overall mortality rate was 1.96% per annum, similar for men with small and medium AAAs. The rAAA risk was 0.03% per annum (95% CI, 0.02%-0.05%) for men with small AAAs and 0.28% (0.17%-0.44%) for medium AAAs. The rAAA risk for men with AAAs just below the referral threshold (5.0-5.4 cm) was 0.40% (0.22%-0.73%).

CONCLUSIONS

The risk of rAAA under surveillance is <0.5% per annum, even just below the present referral threshold of 5.5 cm, and only 0.4% of men under surveillance are estimated to rupture before referral. It can be concluded that men with small and medium screen-detected AAAs are safe provided they are enrolled in an intensive surveillance program, and that there is no evidence that the current referral threshold of 5.5 cm should be changed.

Population screening and intervention for vascular disease in Danish men (VIVA): a randomised controlled trial

BACKGROUND

Abdominal aortic aneurysm is the only cardiovascular disease targeted by population screening. In this study, we test the effect of screening and subsequent intervention for abdominal aortic aneurysm, peripheral arterial disease, and hypertension combined.

METHODS

In this randomised controlled trial, we randomly allocated (1:1) all men aged 65-74 years living in the Central Denmark Region to screening for abdominal aortic aneurysm, peripheral arterial disease, and hypertension, or to no screening. We based allocation on computer-generated random numbers from 1 to 100 in blocks of 1067 to 4392, stratified by 19 municipalities. Only the non-screening group and the investigator assessing outcomes were masked. We invited participants who were found to have abdominal aortic aneurysm or peripheral arterial disease back for confirmation and eventual initiation of relevant pharmacological therapy. We further offered participants with abdominal aortic aneurysm annual control or surgical repair. We referred participants with suspected hypertension to their general practitioner. The primary outcome was all-cause mortality, assessed 5 years after randomisation, analysed in all randomly allocated participants except for those who had incorrect person identification numbers. This trial is registered at ClinicalTrials.gov, number NCT00662480.

FINDINGS

Between Oct 8, 2008, and Jan 11, 2011, we randomly allocated 50 156 participants, with 25 078 (50%) each in the screening and non-screening groups. Four (<1%) participants in the screening group were lost to follow-up. After a median follow-up of 4·4 years (IQR 3·9-4·8), 2566 (10·2%) of 25 074 participants in the screening group and 2715 (10·8%) of 25 078 in the non-screening group had died. This finding resulted in a significant hazard ratio of 0·93 (95% CI 0·88-0·98; p=0·01), an absolute risk reduction of 0·006 (0·001-0·011), and a number needed to invite of 169 (89-1811). Incidences of diabetes (3995 per 100 000 person-years in the screening group vs 4129 per 100 000 person-years in the non-screening group), intracerebral haemorrhage (146 vs 140), renal failure (612 vs 649), cancer (3578 vs 3719), or 30 day mortality after cardiovascular surgery (44·57 vs 39·33) did not differ between groups.

INTERPRETATION

The observed reduction of mortality risk from abdominal aortic aneurysm, peripheral arterial disease, and hypertension has never been seen before in the population screening literature and can be linked primarily to initiation of pharmacological therapy. Health policy makers should consider implementing combined screening whether no screening or isolated abdominal aortic aneurysm screening is currently offered.

FUNDING

The 7th European Framework Programme, Central Denmark Region, Viborg Hospital, and the Danish Council for Independent Research.

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.

Methods

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).

Long term outcomes in men screened for abdominal aortic aneurysm: prospective cohort study

OBJECTIVE

To determine whether there is a relation between aortic diameter and morbidity and mortality in men screened for abdominal aortic aneurysm.

DESIGN

Prospective cohort study.

SETTING

Highland and Western Isles (a large, sparsely populated area of Scotland).

PARTICIPANTS

8146 men aged 65-74.

MAIN OUTCOME MEASURES

Morbidity and mortality in relation to presence of abdominal aortic aneurysm and three categories of aortic diameter (≤ 24 mm, 25-29 mm, and ≥ 30 mm).

RESULTS

When screened, 414 men (5.1%) had an aneurysm (diameter ≥ 30 mm), 669 (8.2%) an aortic diameter of 25-29 mm, and 7063 (86.7%) an aortic diameter of ≤ 24 mm. The cohort was followed up for a median of 7.4 (interquartile range 6.9-8.2) years. Mortality was significantly associated with aortic diameter: 512 (7.2%) men in the ≤ 24 mm group died compared with 69 (10.3%) in the 25-29 mm group and 73 (17.6%) in the ≥ 30 mm group. The mortality risk in men with an aneurysm or with an aorta measuring 25-29 mm was significantly higher than in men with an aorta of ≤ 24 mm. The increased mortality risk in the 25-29 mm group was reduced when taking confounders such as smoking and known heart disease into account. After adjustment, compared with men with an aortic diameter of ≤ 24 mm, the risk of hospital admission for cardiovascular disease and chronic obstructive pulmonary disease was significantly higher in men with aneurysm and those with aortas measuring 25-29 mm. Men with an aneurysm also had an increased risk of hospital admission for cerebrovascular disease, atherosclerosis, peripheral arterial disease, and respiratory disease. In men with aortas measuring 25-29 mm, the risk of hospital admission with abdominal aortic aneurysm was significantly higher than in men with an aorta of ≤ 24 mm (adjusted hazard ratio 6.7, 99% confidence interval 3.4 to 13.2) and this increased risk became apparent two years after screening.

CONCLUSIONS

Men with abdominal aortic aneurysm and those with aortic diameters measuring 25-29 mm have an increased risk of mortality and subsequent hospital admissions compared with men with an aorta diameter of ≤ 24 mm. Consideration should be given to control of risk factors and to rescreening men with aortas measuring 25-29 mm at index scanning.

Socioeconomic position, comorbidity, and mortality in aortic aneurysms: a 13-year prospective cohort study

BACKGROUND

To evaluate factors associated with incidence and 3-year all-cause mortality in patients with aortic aneurysm (AA). The design is sex and age-stratified (60-79 and 80-90 years) prospective cohort. By using the population register, we constituted a cohort of all men and women born between 1900 and 1930 and living in Scania by 1991, and followed them for 13 years. Identification of AA was based on hospital discharge diagnosis obtained from the Swedish Patient Register or from the information on death certificates from the Cause of Death Register.

METHODS

We applied stepwise Cox regression and investigated both AA incidence (1991-2003) as well as 3-year survival after the first hospitalization for AA.

RESULTS

We found an inverse relation between AA incidence and previous hospitalization by diabetes mellitus in women (hazard ratio [HR]: 0.41; 95% confidence interval [CI]: 0.19-0.88) and in men (HR: 0.38; 95% CI: 0.24-0.61) aged 60-79 years. Three-year all-cause mortality after diagnosis of AA was 58.6% in women, 50.2% in men, 72.9% in octogenarians, and 43.7% for nonoctogenarians. Low income, chronic respiratory diseases, cerebrovascular diseases, dementia, systemic connective tissue disorders, renal failure, and malignant neoplasms were independent factors for mortality in 60-79-year-old men with AA.

CONCLUSIONS

Inferior socioeconomic position is associated with increased 3-year all-cause mortality in 60-79-year-old men with AA.

The Viborg Vascular (VIVA) screening trial of 65-74 year old men in the central region of Denmark: study protocol

BACKGROUND

Screening for abdominal aortic aneurysm (AAA) of men aged 65-74 years reduces the AAA-related mortality and is generally considered cost effective. Despite of this only a few national health care services have implemented permanent programs. Around 10% of men in this group have peripheral arterial disease (PAD) defined by an ankle brachial systolic blood pressure index (ABI) below 0.9 resulting in an increased mortality-rate of 25-30%. In addition well-documented health benefits may be achieved through primary prophylaxis by initiating systematic cholesterol-lowering, smoking cessation, low-dose acetylsalicylic acid (aspirins), exercise, a healthy diet and blood-pressure control altogether reducing the increased risks for cardiovascular disease by at least 20-25%. The benefits of combining screening for AAA and PAD seem evident; yet they remain to be established. The objective of this study is to assess the efficacy and the cost-effectiveness of a combined screening program for AAA, PAD and hypertension.

METHODS

The Viborg Vascular (VIVA) screening trial is a randomized, clinically controlled study designed to evaluate the benefits of vascular screening and modern vascular prophylaxis in a population of 50,000 men aged 65-74 years. Enrolment started October 2008 and is expected to stop in October 2010. The primary outcome is all-cause mortality. The secondary outcomes are cardiovascular mortality, AAA-related mortality, hospital services related to cardiovascular conditions, prevalence of AAA, PAD and potentially undiagnosed hypertension, health-related quality of life and cost effectiveness. Data analysis by intention to treat.

RESULTS

Major follow-up will be performed at 3, 5 and 10 years and final study result after 15 years.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00662480.