Screening of

abdominal aortic aneurysm :

Luxury or necessity?

H. Van Damme(C.H.U. Sart Tilman Liège)

M. SpryngerJC Wautrecht

on behalf the BelgianWorkingGroup on Angiology

definition

Screening identifies apparently healthy people

who may be at increased risk of a disease or condition,

enabling earlier treatment

aim

AAA screening aims to reduce AAA related mortality

Screening of AAA

4 questions:

Natural history of AAA

Prevalence of AAA in western world? Population at risk?

Once an AAA(>30 mm) is detected, what is the optimal surveillance program?

Does a single US screening at 65 years of ageimprove life-expectancy?

AAA size annual rupture rate

30-40 mm

40-50 mm

50-60 mm

60-70 mm

> 70 mm

< 1%

2 %

5-9 %

15 %

> 20 %

estimated yearly rupture rate based on AAA size

higher rupture risk in women !

threshold sizefor repair

37 mm AAA2016

56 mm AAA2017

32 mm2015

AAA growth over a 4 y period of screening

30 mm 2014

Cause-specific mortality in Belgium in 2015

1. Cardio-vascular (ischemic heart disease & stroke)……28%2. Cancer………………………………………………………..26%3. Respiratory………………………………………………..11%4. …………………………5. ………………………….6. …………………………..7. ……………………………8. ………………………….9. ………………………….10. ………………………….11. …………………………..

12. AAA-related mortality…………………………..0.32% (360 / 110 588)♂ 0.49% ♀ 0.16%

In Sweden : ……………………. 0.1 % (Lancet 2018, 391 : 2441 – 47)

AAA screening in Upsala county (Sweden 2006 - 2010)

26 256 men aged 65 y were invited => [ 85 % attendance rate] n = 22 187

1.7 % of the screened men (65 y)

had new diagnosis of AAA ( n = 373 ) > 30 mm+ 0,5% men with known or operated AAA :

total prevalence of 2,2% of Swedish

65 y male population in 2010

1.4 % (80 % of all screening 30 – 45 mmdetected AAAs)

0.2 % 46 – 54 mm

Svensjö Circulation 2011 , 124 : 1118 – 1123 Swedish Aneurysm Screening Study(2006-2015) Circulation 2016;134:1141-8,

1.7% >30 mm

0.1% >55 mm

0.1 % > 55 mm

optimal target group at highest risk (>5% prevalence) for aneurysmal diseaseO.R.

men aged >64 y 5.7smokers 3.2 – 12.13family history 3.8 hypertension 1.25 COPD 2.0PAOD 1.6diabetes 0.7

=> selective targeted AAA screening based on risk factors

At the age of 65 to 75 years : prevalence of AAA (> 30 mm) in ♂ smokers = 6.5%♂ non-smokers = 2.0%♀ smokers = 2.0%♀ non-smokers = 0.6%

Society of Vascular Surgery Practice Guidelineson the care of patients with AAA

J Vasc Surg 2018,67 : 2 – 77.

½ pq cigarettes a day during 10 years => OR=2.61 pq cigarettes a day during 35 years => OR=12.3

Gloucestershire study (2001) :

Crow , Earnshaw Br J Surg 2001 , 88 : 941 – 944.

MASS trial Br J Surg 2012 , 99 : 1649 – 1656

Should we consider* re-screening at a higher age ? ( a 65 y old man has a 15 y life expectancy dd.2015)

*selective targeted screening among smokers ?

Is this still true with improved longevity

and modified life-style

with reduced exposure to risk factors ?

« a single normal ultra-sound scan at the age of 65 yeffectively rules out the risk

of clinicaly relevant aneurysmal disease for life in men. »

Decline in cigarette consumption per person per year since 1970coincides with decrease in prevalence of AAA related deaths

Lederle Circulation 2011 (sept) , 124 : 1097 - 1099

the U.S.A.prevalence of AAA in men aged 65 y decreased from 4.5 % in 1995 to < 2 % in 2015of daily 65 y male smokers decreased from 32 % in 1980 to 11 % in 2007

Multi-center Aneurysm Screening Study (U.K. 1997 - 1999)

a 13 year F.U.

67770 men 65 – 74 years oldscreened group control group (not screened at age 65 y)

n=33883 n=33887 RR ARR

1334 (4.9 %) AAA detected i incidentally detected AAA

============================================================================elective AAA repair 600 (1.8%) + 217 % 277 2.17

rAAA repair 80 - 48 % 166 0.52

AAA related deaths 224 (0.66%) - 42 % 381 (1.12%) 0.58 0.16%

NNS = 606

MASS (13 y follow-up) : Br J Surg 2012 , 99 : 1649 - 1656

M.A.S.S.

one-time AAA screening allows to detect and manage earlier AAAs witha significant 48% reduction in AAA rupture rate

(ARR of 6/104 rAAAs in screened men, compared with the non-screened group)

Multi-center Aneurysm Screening Study (U.K. 1997-1999)

MASS-trial

A 42% reduction of AAA related death over a 13 y F.U.

MASS 13 y follow-up : Br J Surg 2012 , 99 : 1649 - 1656

1.12 %

0.66 %

42% RRR

Meta-analysis of AAA screeningAnn Vasc Surg 2019, 54: 1 – 9.

VIVA trial , Western Australian trial , MASS trial , Chichester trial , Viborg trial 2017 2016 2012 2007 2010 4,4 y F.U. 12,8 y F.U. 13,1 y F.U. 9,8 y F.U. 13 y F.U.

175 085 pts (64 – 83 y)80 % attendance rate to screening invitation

AAA detection rate = 1,5 %

Reduced all-cause mortality (RR = 0,97 ; p = 0,002)

Reduced AAA related mortality (RR = 0,65 ; p = 0,008) RRR = 35 %

Less emergent AAA repair (RR = 0,64 ; p = 0,02) - 36%

Increased elective repair (RR = 1,94 ; p = 0,001) + 94%

number needed to screen to prevent 1 AAA-related death over 10 years = 450

are « sub-aneurysmal »

screen-detected aortas innocious ?

Individuals with a « sub-aneurysmal aorta »(25-29 mm) at the age of 65 y will probably live long enough to develop a « de novo » aneurysm as time goes by

% of progression to an AAA of 5.5 cm over time in function of the initial diameter at screening

from Oliver-Williams (Gloucester-shire study)Br J Surg 2018;105 : 68 - 74

sub-aneurysmal aorta

28%

of

55

mm

AA

A

of the initial sub-aneurysmal aortas, 28% will progress to 5.5 cm or more within 15 years

a re-screening of sub-aneurysmal aortas every 5 - 10 year is recommended

one-time AAA screening for ♂ and ♀ 65 to 75 y old who ever smoked(level 1)

one-time AAA screening for ♂ and ♀ 55 to 75 y with family history of AAA(level 2)

Surveillance rescreening for AAA2.5 – 2.9 cm => rescreening at 5 - 10 y.3.0 – 3.9 cm => 3 y interval4.0 – 4.9 cm => 1 y interval5.0 – 5.5 cm => 6 mths interval

(level 2)

Rescreening intervals to check for AAA expansion shorten as the AAA diameter enlarges

U.S.Preventive Services Task Force recommendation up-date JAMA 2019;322 : 2211 - 2218

* in daily practice, only 35% benefit of rescreening F. U.* no follow-up for 30 to 45 mm AAA in octogenarians (leave their AAA untreated !) ( J Vasc Surg 2020, in press)

J Vasc Surg 2018;67 : 2 - 77

J Vasc Surg 2018 ; 67 (1) : 2 – 77.

identical ESC2014 guidelines

European Society of Cardiology Eur Heart J 2014; 35 : 2873 – 2927.

statins attenuate oxidative stress and inflammation inside the aortic wall

Final remarks :

the goal of AAA screening is to facilitate prophylactic intervention once the threshold size of AAA (55 mm) is reached

* ruptured AAA causes <0.5 % of all deaths

* the age at which AAA become clinically relevant (>55 mm) has increased by 10 years(attenuated growth rate)

* most ( 80 %) patients with an AAA detected by screening die of AAA-unrelated causes

* most (90 % ) screening detected AAAs are small (30- 55 mm) , requiring further surveillance

* mass screening resulted in a significant increase (1.8 times more likely) in the number of elective AAA repairs in an early stage (55 mm) (EVAR or open)

* mass screening results in a 35% reduction of the incidence of ruptured AAA

* no benefit of screening in non-smoking women

* minimal benefit of screening elderly men (>75 y)

* no difference in Health Related Quality of Life between screened positive and control groups (screened negative or no AAA) (transient reduction of mental health by anxiety up to 12 mths)

Review on AAA-screening : J Vasc Surg 2016 , 64 : 1855 - 1868

• mass screening for AAA reducesAAA-related mortality with 42 %(RRR) at 11 y F.U.

vs 20% RRR in death from breast-cancer by mass screening

0.66% AAA-related deaths in screened ≥65 y men vs 1.12% in non-screened men

( ARR =0,46 % ; NNS = 216)

all-cause mortality with 3% (RRR)

modified life style, better medical treament, less exposure to risk factors

less fatal ruptured AAAs , increased awareness of AAA

° low false positive rate (accurate)

(<1% versus 19% after mammography for breast cancer screening)

° risk of « overdiagnosis » (diagnosis of a condition that would never causesymptoms or death during patient’s life-time)

Ying : meta-analysis : Ann Vasc Surg 2019 , 54 : 298 – 303 MASS (13 y follow-up) : Br J Surg 2012 , 99 : 1649 – 1656Takagi : Angiology 2018;69:205-211

Societal willingness to pay threshold of 50,000-$ / QALY

( 25,000-$ in U.K.)

AAA screening………………………16,854-$/QALY(a single echography at age of 65 y)

breast cancer screening……..32,000-$/QALY(a repetitive mammography for ♀ aged 50 y every 2 years +- biopsy)

NNT screen to prevent1 AAA or CA related death 216 1500

*nevertheless , today the Belgian Task Force on Preventive Health Care is not favorable to routine mass-screening for AAA (budget restraints !)

*since 2007 Medicare program covers a free 1-time screening to men 65 y whoever smoked and to adults with a family history of AAA (< 15 % attendance !!)

*only in U.K.(2009, NAAASP) and in Sweden(2006) a nation-wide AAA-screening program is implemented (80% attendance rate , 1,5% AAA detection rate)in GPs , local hospitals , flu-clinics, commercial venues , exhibition fairs…..

opportunistic screening for AAA subsequent to trans-thoracic cardiac echography in patients > 65 y

additional time = 2 min.

AAA detected in 3.7 % of men (vs 1.7 % in mass screening)

1.3 % of women (vs 0.5% in mass screening)

+

E2T3A study (France, 76 centers, 1338 combined echographies)Am J Cardiol 2014 ; 114 : 1100 - 1104

Up-dated benefit of mass AAA screening

0.02 % reduction in AAA related deaths(2 AAA deaths avoided for every 10 000 screened men at 6 year F.U.)

49 overdiagnosed AAA for every 10 000 screened men19 « avoidable » AAA surgeries for every 10 000 screened men(treatment of AAA that would never have caused symptoms nor death during patient’s life)

Swedish registry, mass screening since 2006Lancet 2018 ; 391 : 2441 - 2447

Screening of

abdominal aortic aneurysm :

Luxury or necessity?

H. Van Damme(C.H.U. Sart Tilman Liège)

M. SpryngerJC Wautrecht

on behalf the BelgianWorkingGroup on Angiology