A community screening programme for abdominal aortic aneurysms

Three-hundred and sixty-nine unselected men aged 65-79 years were invited for screening for abdominal aortic aneurysm. One hundred and forty-one men were examined and 4 aneurysms detected. 43.2% of men aged 65-74 attended for examination in response to a single unsolicited letter of explanation with the date of an appointment, but only 29.1% of those aged 75-79 years. It is suggested that community mortality from ruptured aortic aneurysm could be reduced by ultrasound screening of the aorta in men aged 65-74 years and early selective aneurysm surgery.     

Hospital costs and benefits of screening for abdominal aortic aneurysms. Results from a randomised population screening trial.

OBJECTIVES: to analyse the hospital costs and benefits of screening older males for abdominal aortic aneurysm (AAA). MATERIALS and METHODS: in 1994 a hospital-based screening trial of 12 658 65-73-year-old males was started. AAA >5 cm were referred for surgery. The remaining AAA were offered annual scans. Those with aortic ectasia were rescreened at 5 yearly intervals. AAA-operations and hospital AAA-related deaths were researched. The costs of screening, surveillance, and treatment were also registered. RESULTS: the attendance rate was 76%; of whom 191 (4.0%) had AAA. Mean observation time was 5.13 years. Sixty in the screened and 41 in the control group were operated (p=0.06), of which 7 and 27 respectively were operated as an emergency (p<0.001), and 6 and 19 respectively died due to AAA (p=0.009). The costs per scan were 83.50 DKK, 81 400 DKK per emergency operation (71 485 DKK after screening), and 117 000 DKK per emergency operation. The cost per prevented hospital death was 67 855 DKK, equivalent to approximately life year saved approx. 7540 DKK (GBP1=12 DKK). CONCLUSION: screening appears to reduce hospital AAA mortality and to be cost-effective.     

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腹主动脉瘤腔内修复术 (ｅｎｄｏｖａｓｃｕｌａｒｒｅｐａｉｒ,ＥＲ)是指经股动脉导入人工血管 ,以内支架固定于腹主动脉壁上 ,将血液与瘤壁隔离 ,使瘤壁免受血流压力冲击 ,达到治疗目的。1991年Ｐａｒａｄｉ等[1 ] 首先报道应用于临床治疗腹主动脉瘤 ,国内由景在平等[2 ] 于 1998年首先报道。由于其创伤小、恢复快、并发症少 ,近期疗效满意 ,10余年来迅速发展 ,被认为是腹主动脉瘤治疗史上的一个里程碑。有关其中长期疗效的报道不多 ,现将国外近年来的研究介绍如下。1　回顾性研究显示疗效满意Ｂｕｓｈ[3] 1998年报道来自于 98个欧洲研究…     

Mortality from ruptured abdominal aortic aneurysms. A comparison of two series

Series of ruptured abdominal aortic aneurysms from a municipal teaching hospital and from a group of private surgeons practicing at four community hospitals were compared for hemodynamic status and time to operation, as well as mortality. The overall mortality rate was 61 percent for the municipal hospital series and 32 percent for the community hospital series, which was significantly different (p = 0.003). The municipal hospital series had a significantly greater number of patients in shock before operation, as well as a greater number of patients transported directly to the operating room. The community hospital series had a significantly greater number of patients with a more than 6 hour delay in diagnosis and delays in surgical exploration. When those patients in shock who were brought directly to the operating room were compared, there was no statistical difference between the two series. Further reviews of ruptured abdominal aortic aneurysms should attempt to identify groups of patients by their hemodynamic status when evaluating treatment.     

Ultrasonic screening for the detection of abdominal aortic aneurysms

Detection of aortic aneurysms before they rupture is imperative if the mortality rate from this disease is to be reduced. Although large aneurysms frequently are palpable, small aneurysms--especially in obese patients--are seldom recognized on physical examination. Ultrasound, which is noninvasive, relatively inexpensive, and nearly 100 per cent accurate in identifying the presence or absence of aneurysms, is well suited to screening. In high-risk populations (patients over the age of 50 with coronary artery or peripheral vascular disease), ultrasonic screening is probably cost-effective.     

A screening program to identify risk factors for abdominal aortic aneurysms.

BACKGROUND: We aimed to explore the feasibility of a nurse-supervised aneurysm screening program to identify any independent risk factors for abdominal aortic aneurysm (AAA) formation in high-risk patients. METHODS: We conducted a prospective observational study of 90 male patients in a university- affiliated hospital in southern Ontario. The patients were prospectively evaluated and all underwent abdominal ultrasonography, with the main outcome measure being detection of an AAA. RESULTS: AAAs were identified in 18 patients (20%) and had a mean diameter of 3.6 (range 2.8-6.0) cm. A separate analysis was performed to identify risk factors for the presence of an aneurysm. The presence of carotid artery disease proved to be the only statistically significant independent predictor of the presence of AAA (odds ratio 2.23, 95% confidence interval 1.76-2.56). CONCLUSIONS: This study confirms the feasibility of a nurse-supervised AAA screening program, and on the basis of these results we recommend ultrasonographic screening for AAA in patients with a history of carotid artery disease.     

The case against a national screening programme for aortic aneurysms.

This review examines the assumptions underlying the calls for a national screening programme for aneurysms. It concludes that on the basis of published evidence, many of the necessary criteria for any putative screening programme are not met for this disease. Although the disease is an important cause of death, and a screening method is available, we lack basic knowledge about the natural history of the disease, especially small aneurysms, and about the cost-effectiveness of a screening programme. In particular, the treatment is an operation which, nationwide, carries a high mortality and is likely to be unacceptable to many patients. The consequences of such a programme would be to diagnose many small aneurysms, for which the best treatment remains unclear, and which will engender much unnecessary anxiety among patients so diagnosed.     

Psychological consequences of screening for abdominal aortic aneurysm and conservative treatment of small abdominal aortic aneurysms.

OBJECTIVE: To describe the potential psychological consequences of screening for abdominal aortic aneurysms (AAAs). METHODS: The participants were prospectively and randomly sampled from a randomised screening trial for AAA and asked to complete a validated generic and global anonymous quality of life (QL) questionnaire by self-assessment (ScreenQL). Material case-control study: ScreenQL was completed once by 168 (48%) of 350 non-responders to screening, 271 (81%) of 335 attenders before screening, 286 (85%) of 335 attenders after screening, 127 (85%) of 149 with a small AAA diagnosed at screening, and 231 (66%) of 350 who were randomised not to be offered screening for AAA (controls). Prospective study (paired data): 127 men having a small AAA diagnosed. Twenty-nine (81%) of 36 men operated after initial conservative treatment. RESULTS: Initially, the QL score was 5% lower among men with a small AAA compared to the controls (p<0.05), mainly because of poorer health perception. The QL score declined significantly further to 7% below control values during the period of conservative treatment. This impairment was mainly due to a 21% and 15% reduction in scores relating to health perception and psychosomatic distress, respectively. However, all scores improved to control levels in patients operated on. The QL of attending men for screening was significantly lower than that of the controls and the attenders after the screening. No differences were noticed concerning the non-attenders. CONCLUSION: The offer of screening causes transient psychological stress in subjects found not to have AAA. However, diagnosis of an AAA seems to impair QL permanently and progressively in conservatively treated cases. This impairment seems reversible by operation. Nevertheless, the impairment seems considerable, and must be considered in the management of AAA and in the final evaluation of screening for AAA.     

Optimal interval screening and surveillance of abdominal aortic aneurysms.

OBJECTIVES: to determine safe and optimal intervals of rescreening and surveillance for AAA. METHODS: hospital-based mass screening of 6339 65-73-year-old men from 1994-98. 76.4% attended. One hundred and ninety-one (4%) had AAA53 cm. Twenty-four (0.5%) were initially >5 cm and referred for surgery, while the rest were offered annual control scans to check for expansion. Later, all 348 (7.5%) men who 3 to 5 years ago had an ectatic aorta (infrarenal aortic diameter of 25-29 mm or distal/renal aortic diameter ratio >1.2) were offered rescreening. Of these, 62 (18%) died before rescanning, while 248 of the survivors attended rescreening (87%). Furthermore, a random sample of 380 of those with non-ectatic aortas were offered rescreening. Of these, 49 (13%) died before rescreening (p=0.06), while 275 (83%) of the survivors attended re-screening. RESULTS: none of the controls had developed AAA. Of those who initially had an 25-29 mm aorta, 29% had developed AAA (size range 30-48 mm) with expansion rates varying from 1.0 to 4.7 mm/year. Only 3.5% with a ratio >1.2 developed AAA (size range: 30-34 mm) with expansion rates from 1.3 to 2.4 mm/year. During the fourth year of surveillance some AAA initially sized below 3.5 cm expanded to above 5 cm, while some sized 3.5-3.9 cm did so during the second year, >4 cm did so during the first year of surveillance. CONCLUSION: rescreening for AAA can be restricted to initially ectatic aortas sized 25-29 mm at 5-year intervals. Surveillance of small AAA can be restricted to 1-4 year intervals.     

Implications of screening for abdominal aortic aneurysms on surgical workload

BACKGROUND: The Multicentre Aneurysm Screening Study (MASS) provided strong evidence for both the clinical benefit and the cost-effectiveness of a screening programme for abdominal aortic aneurysms (AAAs) in men. If a national screening programme for AAA were adopted in the UK, it would be expected to increase the elective and decrease the emergency surgical workload. METHODS: The MASS trial randomized 67,800 men aged 65-74 years to be invited to attend for ultrasonographic screening for AAA or to a control group that received no invitation. Predictions of elective and emergency surgical workload were made for a 20-year interval after the introduction of a screening programme for 65-year-old men, based on surgical rates observed in the MASS trial and national mortality statistics. RESULTS: For a district general hospital serving a population of 400,000, there was an estimated reduction from nine emergency operations per year before introduction of the screening programme to three emergency operations annually in men aged 65 years and over by the end of the 20-year interval, and an increase from 24 to 43 AAA operations overall. The corresponding estimated annual costs for all AAA surgery increased by 47 per cent, from pound 209,000 to pound 308,000. These results were not affected by changes in the underlying assumptions. CONCLUSION: The results support the expectation of very few emergency operations, and principally elective operations, being performed following the introduction of a screening programme. For a typical district general hospital, a screening programme would be expected to lead to two additional elective AAA operations per month, and to save 11 AAA-related deaths per year.     

The management of ruptured abdominal aortic aneurysms: screening for abdominal aortic aneurysm and incidence of rupture

Twenty-five years have passed since the first randomised controlled trial began its recruitment for screening for abdominal aortic aneurysm (AAA) in men aged 65 and above. Since this and other randomised trials, all launched in the late 80s and 90s of the last century, the epidemiologic profile of abdominal aortic aneurysm may have changed. The trials reported an AAA prevalence in the range of 4-7% for men aged 65 years or more. AAA-related mortality was significantly improved by screening, and after 13 years, the largest trial showed a benefit for all-cause mortality. Screening also was shown to be cost-effective. Today, there are studies showing a substantial decrease of AAA prevalence to sometimes less than 2% in men aged ≥ 65 years and there is evidence that the incidence of ruptured aneurysm and mortality from AAA is also declining. This decline preceded the implementation of screening programmes but may be due to a change in risk factor management. The prevalence of smoking has decreased and there has been improvement in the control of hypertension and a rising use of statins for cardiovascular risk prevention. Additionally, there is a shift of the burden to the older age group of ≥ 75 years. Such radical changes may influence screening policy and it is worth reflecting on the optimum age of screening - it might be better to screen at ages >65 years - or rescreening 5 to 10 years after the first screen.     

A population based screening of abdominal aortic aneurysms (AAA)

The prevalence of abdominal aortic aneurysm (AAA) in a defined population of elderly men and its correlation to some risk factors were studied in the population cohort "men born in 1914 from Malm?". A total of 499 were invited to attend and 375 (75%) did so. The aorta could be visualised with ultrasound in 364 patients, 39 (10.7%) of whom had aneurysmal changes. The presence of an AAA was related to the findings at a general health examination undertaken 5 years previously. Tobacco and alcohol consumption, impaired lung function and a history of angina pectoris were related to the presence of an AAA. No relationship was found between an AAA and hypertension, hyperlipidaemia or hyperglycaemia. A decreased tissue elasticity as a common denominator for the lung function impairment and development of AAA is discussed.     

The influence of screening on the incidence of ruptured abdominal aortic aneurysms.

PURPOSE: The purpose of this study was to estimate the influence of a screening program on the incidence and mortality of ruptured abdominal aortic aneurysms (RAAAs). METHODS: The effects of screening on the incidence and death rate of RAAAs were investigated with a stepped wedge study design. RAAAs that occurred in the Huntingdon district were traced with an examination of all hospital records and community postmortem records. RESULTS: During the 5-year period from 1991 to 1996, 78 RAAAs occurred in the Huntingdon district: 62 in men and 16 in women. Eleven of the 62 men with RAAAs had been invited for screening. The incidence of RAAA in the invited group was 3.7 per 10,000 person-years (py; 95% confidence interval [CI], 1.5 - 7.3). In the noninvited group, the incidence was 7.3 per 10,000 py (95% CI, 5.3. - 9.2), a rate ratio of 0.51 (95% CI, 0.26 - 0.97). The mortality of rAAAs in the invited group was 3.0 per 10, 000 py (95% CI, 1.4 - 5.4) as compared with 5.4 per 10,000 py in the noninvited group (95% CI, 3.9 - 7.3), resulting in a rate ratio of 0. 55 (95% CI, 0.26 - 1.15). CONCLUSION: Screening for asymptomatic AAAs can reduce the incidence rate of RAAAs by 49% (95% CI, 3% - 74%).     

Endovascular repair for abdominal aortic aneurysms: initial experience of an endograft programme

OBJECTIVE: To evaluate early clinical results of elective endovascular repair of abdominal aortic aneurysms during the initial phase of an aortic endograft programme and to compare them with conventional open surgery. METHODS: Between July 1999 and September 2001, all patients with infrarenal abdominal aortic aneurysms undergoing elective repair were studied. The results of endovascular repair were compared with those of conventional repair. RESULTS: Twenty-seven endovascular repairs (24 men and three women; mean age, 74 yr) and 25 conventional repairs (19 men and six women; mean age, 73 yr) for infrarenal abdominal aortic aneurysms were evaluated. The aneurysm diameters in the two groups were similar (mean, 6.1 cm in the endovascular repair group and 6.6 cm in the conventional repair group). The comorbidities of the two groups were also comparable. The duration of operation was longer in the endograft group (249 +/- 86 min vs. 206 +/- 56 min), while the blood loss was significantly less (600 +/- 486 mL vs. 1074 +/- 1220 mL). The length of stay in the Intensive Care Unit (ICU) and the overall duration of hospitalization was also significantly less in the endograft group (1 +/- 1 d vs. 3 +/- 2 d in ICU; 9 +/- 5 d vs. 13 +/- 6 d of hospitalization). There was one hospital death in each group (4%), and the complications were similar between the two groups. During a mean follow-up period of 11.6 +/- 7.5 months, there was no rupture or open conversion in the endograft group. CONCLUSIONS: In the initial phase of the aortic endograft programme, the mortality and morbidity were acceptable and comparable to that of open surgery.