Screening for PAD in the general population

» Des pas pour la vie« - »steps for life«

Lessons of a French screening program

Böge G, Laroche JP , Benshali Y , Lorin C , Brisot D , Perez-Martin A , Dauzat M , P Carpentier , JL Bosson , C Rolland , C Genty , Becker F , Quéré I.

Background • PAD indicates general atherosclerosis and is associated with

increased mortality• ABI is correlated

– with severity of PAD – and with elevated general and cardiovascular mortality (ABI < 0.9 or >

1.3)– With diminished QoL

• PAD is frequent, underdiagnosed, although medical therapy is known to reduce morbidity and mortality rates in these patients

- Relationship of high and low ankle brachial index to all-cause and cardiovascular disease mortality: the Strong Heart Study. Resnick HE, Lindsay RS, McDermott MM, Devereux RB, Jones KL, Fabsitz RR, Howard BV. Circulation. 2004 Feb 17;109(6):733-9- A high ankle-brachial index is associated with increased cardiovascular disease morbidity and lower quality of life. Alison MA, Hiatt WR, Hirsch AT, Coll JR, Criqui MH, J Am Coll Cardiol.2008;51(13):1292-8

Feringa H et al, Cardioprotective medication is associated with improved survival in patients with peripheral arterial disease. J Am Coll Cardiol. 2006;47:1182-1187

Methods

• National screening campaign– general population with no known PAD– Presenting cardiovascular risk factors– Over 60 years old

• One day in France– 58 communities– 79 centers– 350 physicians

• 3 month follow up

Methods

• Questionnaire – Medical history– Cardiovascular risk factors

• ABI measurement– Vascular specialist– Continuous wave Doppler 8 MHz probe– systolic blood pressure

• in both upper extremities• In both lower extremities (posterior and anterior tibial artery)

• ABI calculation– Method 1: ABI= highest ankle pressure/ highest humeral pressure– Method 2: ABI= lowest ankle pressure/ highest humeral pressure

• ABI= highest ankle pressure/ highest humeral pressure– Correlated with the hemodynamic severity of peripheral arterial

involvement – Diagnostic accuracy for PAD (vs angiography) 98%– Usually recommended measurement method

• ABI= lowest ankle pressure/ highest humeral pressure– Cardiovascular risk similar– Higher sensibility: more PAD detected– May bee a better screening tool

ABI: methods of calculation

Different calculations of ankle-brachial index and their impact on cardiovascular risk prediction. Espinola-Klein C, Rupprecht HJ, Bickel C, Lackner K, Savvidis S, Messow CM, Munzel T, Blankenberg S; AtheroGene Investigators. Circulation. 2008 Aug 26;118(9):961-7.

ACC/AHA Guidelines for the Management of patients with peripheral arterial diseaseHirsch et al, Circulation 2006

Results SCREENING DAY

Persons screened 6187

Analyzed 6089

Men mean age

46% 67.6

Women mean age

56% 68.4

Results

ABI < 0.9 or > 1.3 15.4 %

0.70< ABI < 0.90 5.4%

ABI < 0.70 1.8%

ABI > 1.30Uncompressible

7.7%0.6%

ABI= highest ankle pressure/ highest humeral pressure

Results

ABI < 0.9 or > 1.3 24.7%

0.70< ABI < 0.90 13%

ABI < 0.70 4.1%

ABI > 1.30Uncompressible

7.1%0.6%

ABI= lowest ankle pressure/ highest humeral pressure

Results

1 2 3 4 5 6 7

Risk factors

Abnormal ABI(< 0.9 or > 1.3)

ResultsABI < 0.9 or > 1.3 Odds ratio 95% CIDiabetes (insulin therapy) 2.4 1.58 - 3.64

Male 1.85 1.59 - 2.16

Smoking 1.74 1.36 - 2.16

age > 70 1.58 1.36 - 1.84

Renal impairment 1.56 1.04 - 2.36

Diabetes (oral antidiabetics) 1.49 1.17 - 1.89

History of MI 1.37 1.04 - 1.82

North vs south 1.29 1.06 - 1.58

Hypertension medication 1.17 1.00 - 1.37

Lipid lowering therapy 1.11 0.92 - 1.34

Daily walking (30min) 0.78 0.67 - 0.91

Three month follow-up

• 692/1500 patients: telephone follow up at 3 months

• 42% of them had have a complete duplex scan of the lower extremities, confirming the PAD.

• 30% lifestyle correction (diet, physical activity)• Only 2% had modified medical treatment

Screening of peripheral arterial diseasebased on ABI measurement

Study population PAD prevalence

PARTNERSU.S.Hirsch AT et al, JAMA 2001;286:1317-1324

Primary care offices>70 years or >50 years and diabetes or smokingN= 6979

29%

REGICORSpainRamos R. Eur J Vasc Endovasc Surg 2009 Sep;38(3):305-11

Unselected patients65-74 years 75-79 years N=6262

Men:10.0% Women: 4.6% Men: 17.8% Women:10.6%

GetABIGermanyDiehm C. Atherosclerosis. 2004;175(1);183-4

Primary care offices (GP)Unselected patients >65 years N=6880

Men: 19.8%Women: 16.8%

IPSILONFranceCacoub P. Int J Clin Pract. 2009 Jan;63(1):63-70.

High risk patients presenting in a GP primary care offices(>55 years and presenting at least 2 CV risk factors or history of atherothrombosis)N=5679

27.8%

ELLIPSEFranceMourad JJ. JVS 2009;50:572-80

Asymptomatic high risk in-patients 55-yearsN= 2146

41.1%

Effectiveness of screening

The potential benefit depends of• 1) Disease prevalence (15% -41% in high risk populations)• 2) PAD mortality (3.9%-8.2%/year)

• 3) Screening test available (ABI)• 4) Mortality rate reduction by appropriate therapy ( 25%-

50%)

Hooi et al, asymptomatic peripheral arterial disease predicted cardiovascular morbidity and mortality in a 7 year-follw-up study. J Clin Epidemiol. 2004;57:294-300.Caro J et al, The morbidity and mortality following a diagnosis of peripheral arterial disease: long-term follow-up of a large database. BMC cardiovasc Disor.2005;5:14

Feringa H et al, Cardio protective medication is associated with improved survival in patients with peripheral arterial disease. J Am Coll Cardiol. 2006;47:1182-1187.

Reduction of mortality rates about 2-9 lives/ 100 patients screened/ follow up of 7 years

• “individuals with asymptomatic lower extremity PAD should be identified by examination and/or measurement of the ankle-brachial-index (ABI) so that therapeutic interventions known to diminish their increased risk of myocardial infarction (MI), stroke, and death may be offered”

Class I indication

ACC/AHA Guidelines for the Management of patients with peripheral arterial diseaseHirsch et al, Circulation 2006; 113:1474-1547

Beckman JA et al, The United States Preventive Services Task Force Recommendation statement on screening for peripheral artery disease. More harm than benefit? Circulation 2006;114:861-866

Effectiveness of screening

Conclusion

• Screening of asymptomatic PAD in high risk patients is possible, sure and inexpensive by ABI measurement

• Asymptomatic PAD in the general population > 60 years, presenting CV risk factors, is frequent with a prevalence of about 25%

• PAD is still underdiagnosed, and an undertreated disease• Screening of asymptomatic PAD is effective and life-saving if

therapeutic interventions (lifestyle correction and medical treatment) known to diminish their increased cardiovascular risk are offered