Guidelines

Screening for Abdominal Aortic Aneurysm: A Best-Evidence Systematic Review for the US Preventive Services Task Force{18}

“... screening significantly reduces AAA-related mortality in men age 65 to 80 years”{18}

USPSTF: Recommendation statement{25}

The US Preventive Services Task Force (USPSTF) recommends one-time screening for AAA by ultrasonography in men aged 65 to 75 years who have ever smoked. This is a grade B recommendation {25}

Aetna (US health insurance): Clinical Policy Bulletin: Abdominal Aortic Aneurysm Screening

Aetna considers one-time ultrasound screening for abdominal AAA medically necessary for men aged 65 years of age or older.

Aetna considers AAA screening experimental and investigational for all other indications because its effectiveness for indications other than the one listed above has not been established.

Canadian Society for Vascular Surgery

{24}

1. A population-based screening programme is recommended for men aged 65 to 75 years, who are candidates for surgery (anticipated low perioperative mortality and morbidity) and are willing to participate.

● Evidence grade: high (randomised controlled trial, RCT)

2. Screening provides borderline to no benefit for men of 75 to 80 years old.

● Evidence grade: high (RCT).

3. Population-based screening of women >65 years old is not recommended

● Evidence grade: high (RCT).

4. Individualised investigation with use of women >65 years old with multiple risk factors for AAA (smoking history, cerebrovascular disease, family history of AAA) may be beneficial.

● Evidence grade: moderate (Cohort data from

RCTs, population-based study)

5. Ultrasound is an effective imaging modality for AAA

screening.

● Evidence grade: high (RCT data, cohort studies).

6. In participants found by screening to have an aortic

diameter <3 cm, no follow-up ultrasound is necessary

before 3 to 5 years.

● Evidence grade: high (Cohort study of RCTs )

7. For individuals with aneurysms 3.0 to 4.4 cm, a yearly abdominal ultrasound is an acceptable practice. The true effective interval of re-screening is unknown for this group and it is likely that every 2 years is also acceptable for the smaller aneurysms.

● Evidence grade: moderate (population-based study, six cohort study of tertiary referral centres)

8. Screening individuals with popliteal artery aneurysms is likely to be beneficial.

● Grade: low (systematic review).

9. Screening men or women <65 years old is not likely to be beneficial.

● Grade: high (RCT 95 and population-based studies).

10. Screening men 65 to 75 years old may be cost effective.

● Evidence grade: moderate (cost analysis of RCT data)57 a systematic review of studies of screening costs 55 and projections from real cost data at a Canadian tertiary care centre (unpublished data from McMaster University). Rationale: The cost per life year gained is estimated to be $12,813.

11. A strategy including physical examination and use needs to be investigated to screen AAA.

● Grade: low (metaanalysis of cohort studies and cohort studies of tertiary referral centre).

12. The cost effectiveness of screening programmes for AAA should be re-evaluated if advances in vascular surgery or endovascular techniques improve the mortality of urgent or elective operative intervention for AAA.

● Grade: high (decision analysis of RCT data).

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Consensus statement

Society for Vascular Surgery

“There are compelling data that in appropriately selected patient cohorts identification of AAA can save lives at a cost to society that compares favourably with other well-accepted interventions. Inasmuch as reimbursement remains the major impediment to acceptance of aneurysm screening, we strongly encourage that insurers adopt a policy that allows payment for this life-saving test”{26}

Cut-off point

Cut-off point for repairing asymptomatic AAA in men: 5.5 cm {27}

Quality Assurance (QA)

“QA is an essential component of any national screening programme”{28}

Aims

• reduce the probability of error
• ensure that errors are dealt with competently and sensitively
• help professionals and organisations improve year on year
• set and reset standards (national responsibility)

{28}

Ensuring that the whole screening pathway is functional and safe

• the correct population is identified and invited
• an appropriate invitation is used and men have an informed choice
• it systems are in place to ensure effective tracking of individuals’ progress along the pathway and that their results reach them in a timely way
• action is taken to follow up unscreened men
• men with a positive screen result receive appropriate follow-up including a diagnostic test and information; those with a positive diagnosis receive appropriate and timely treatment

{28}

National, regional and local components

• error prevention and effective management of risks and untoward incidents
• year on year performance assessment and, where appropriate, improvement
• maintenance of clear responsibility for different aspects of screening and the flow of information between those involved in running different components of the screening programme
• production of an annual report on the screening programme at a local and national level

{28}

Tertiary literature “up to date”

One time screening is recommended for men between 65 and 75 if they are (or have been) a smoker or have a family history of AAA. Under special conditions women could also be screened. {Mohler#screening for ...}. The authors are primarily citing the USPSTF guidance.