The True Prevalence of PAD and the Economics of Major Amputation

What are the best estimates of the current prevalence of peripheral artery disease (PAD) in the United States (US)? What are the sources for these data, and what is known about their current accuracy and applicability?

The best estimate for the prevalence of PAD in the US in 2020 is 19 to 21 million. PAD continues to be underestimated.¹ The most commonly quoted number of 8 to 12 million was published in the PARTNERS study.² However, these numbers were not based on the PARTNERS results; the source of the estimate was the prevalence percentage found in a 1985 study in San Diego, California, by Criqui et al.³

Because of its design, the San Diego study understates PAD prevalence. It was conducted in 613 white, upper-middle–class patients aged 38 to 82 years residing in Southern California. Because PAD is significantly more prevalent in African Americans (11% of the US population aged ≥ 45 years), the study understates PAD.^4-6 Furthermore, PAD was defined in the study as an ankle-brachial index (ABI) < 0.80 rather than the standard ABI definition of < 0.90.^3,7-9

The 8 to 12 million number was a good estimate for the US population in and around 1995.¹ Since then, the population has aged and become considerably more diabetic—two key risk factors for PAD.¹ If we apply the Criqui study’s prevalence by age group to the 2020 US population, the result is 12 to 19 million.^1,3 Similarly, calculating PAD based on the prevalence in a study by Nehler et al yields 19 million.¹⁰ Both are similar to the 21 million calculated by the Diabetes Method, which is a population-based method that calculates PAD according to age and glucose status.^1,10

What impact does amputation have on health care costs compared with other treatment methods and/or early screening, both for the patient and the physician? Who ultimately bears the cost?

Major amputation (MA) is the most expensive treatment for critical limb ischemia (CLI), and treatment with primary MA rather than revascularization is an important factor that increases CLI costs.^11,12

Numerous studies of hospital costs in different countries covering varying time periods all show that MA costs more than revascularization with either endovascular or surgical bypass.^13-16 Although initial procedure costs are similar for MA, surgical bypass, and endovascular revascularization, the total costs of amputation are considerably higher due to the increased frequency of procedural morbidity, mortality, and revision amputations.¹²

In 2020, the direct medical costs of MA were $13.4 billion.¹⁷ The majority of these costs are inpatient. Because the Centers for Medicare & Medicaid Services pay almost 80% of the amputation bill, MA is financed by our tax dollars.¹⁸ In addition to initial treatment costs, numerous medical and nonmedical expenses are incurred over an amputee’s lifetime. Many of these are not reimbursed and are paid for by the patient or family. The annual cost of follow-up care for MA exceeds $160,400 per patient; lifetime costs add approximately $11.1 billion, for a total cost of $24.5 billion.¹⁷

MA as a primary treatment for CLI misallocates resources and wastes taxpayer dollars.¹⁷ Amputation also creates tremendous financial, physical, and psychologic burdens for the patient and the patient’s family.^12,17

What possible changes to reimbursement might help reduce the prevalence of amputations performed without exploring other options first, and how would this affect the global costs of PAD care?

Two reimbursement changes could significantly reduce the number of amputations performed as a treatment for CLI: (1) reimbursement for screening in high-risk populations, and (2) denial of reimbursement for amputation if appropriate diagnostic arterial testing is not performed prior to the procedure. Early diagnosis and appropriate treatment could reduce costs and the number of amputations.¹⁷

Screening groups with a high prevalence of PAD, such as those with diabetes who are aged > 50 years, diabetic foot ulcers, prior cardiac or cerebrovascular events, and chronic kidney disease in those aged > 65 years would yield 30% to 50% positive results.^17,19 A significant proportion of these patients would have undiagnosed disease severe enough to require revascularization.^17,19 Treating PAD when the disease is less severe would reduce costs. This reflects the fact that it costs less to treat intermittent claudication than CLI.²⁰ Within CLI, costs increase with Rutherford classification.^11,21,22

Although all patients with PAD should be treated with cardiovascular risk factor modification therapies, risk factors in both intermittent claudication and CLI patients remain undertreated.^23,24 One study found that suboptimal medical management in CLI increases the risk of amputation and/or death by eightfold.²⁴

An angiogram reduces the odds of undergoing amputation by 90%.²⁵ Despite this, 54% to 67% of CLI patients have no angiogram performed prior to MA.^26,27 Consequently, requiring an angiogram prior to MA and denying reimbursement if one is not performed should significantly reduce amputations.

The Amputation Reduction and Compassion Act (HR 8615) has been introduced to change reimbursements in the manner we have described. In addition, HR 8615 would establish a PAD education program to inform health care professionals and the public about PAD and methods to reduce amputations.²⁸

1. Yost ML. Critical limb ischemia volume I, U.S. epidemiology, 2016 supplement. The Sage Group. 2016.

2. Hirsch AT, Criqui MH, Treat-Jacobson D, et al. Peripheral arterial disease detection, awareness, and treatment. JAMA. 2001;286:1317-1324. doi: 10.1001/jama.286.11.1317

3. Criqui MH, Fronek A, Barrett-Connor E, et al. The prevalence of peripheral arterial disease in a defined population. Circulation. 1985;71:510-515. doi: 10.1161/01.cir.71.3.510

4. Allison MA, Ho E, Denenberg JO, et al. Ethnic-specific prevalence of peripheral arterial disease in the United States. Am J Prev Med. 2007;32:328-333. doi: 10.1016/j.amepre.2006.12.010

5. United States Census Bureau. 2019 population estimates by age, sex, race and Hispanic origin: national detailed tables: annual estimates of the resident population for selected age groups by sex for the United States: April 1, 2010 to July 1, 2019. Published June 25, 2020. Accessed April 28, 2021. https://www.census.gov/newsroom/press-kits/2020/population-estimates-detailed.html

6. United States Census Bureau. 2019 population estimates by age, sex, race and Hispanic origin: national detailed tables: annual estimates of the resident population by sex, age, race, and Hispanic origin for the United States: April 1, 2010 to July 1, 2019. Published June 25, 2020. Accessed April 28, 2021. https://www.census.gov/newsroom/press-kits/2020/population-estimates-detailed.html

7. Selvin E, Erlinger TP. Prevalence of and risk factors for peripheral arterial disease in the United States: results from the National Health and Nutrition Examination Survey, 1999-2000. Circulation. 2004;110:738-743. doi: 10.1161/01.CIR.0000137913.26087.F0

8. Savji N, Rockman CB, Skolnick AH, et al. Association between advanced age and vascular disease in different arterial territories: a population database of over 3.6 million subjects. J Am Col Cardiol. 2013;61:1735-1743. doi: 10.1016/j.jacc.2013.01.054

9. Eraso LH, Fukaya E, Mohler ER, et al. Peripheral arterial disease, prevalence and cumulative risk factor profile analysis. Eur J Prev Cardiol. 2014;21:704-711. doi: 10.1177/2047487312452968

10. Nehler MR, Duval S, Diao L, et al. Epidemiology of peripheral arterial disease and critical limb ischemia in an insured national population. J Vasc Surg. 2014;60:686-695.e2. doi: 10.1016/j.jvs.2014.03.290

11. Mustapha JA, Katzen BT, Neville RF, et al. Determinants of long-term outcomes and costs in the management of critical limb ischemia: a population-based cohort study. J Am Heart Assoc. 2018;7:e009724. doi: 10.1161/JAHA.118.009724

12. Yost ML. Cost-benefit analysis of critical limb ischemia in the era of the Affordable Care Act. Endovasc Today. 2014;13:29-30, 32, 34-36.

13. Malone M, Lau NS, White J, et al. The effect of diabetes mellitus on costs and length of stay in patients with peripheral arterial disease undergoing vascular surgery. Eur J Vasc Endovasc Surg. 2014;48:447-451. doi: 10.1016/j.ejvs.2014.07.001

14. Kearns BC, Michaels JA, Stevenson MD, Thomas SM. Cost-effectiveness analysis of enhancements to angioplasty for infrainguinal arterial disease. Br J Surg. 2013;100:1180-1188. doi: 10.1002/bjs.9195

15. Economic aspects of peripheral arterial disease. Eur J Vasc Endovasc Surg. 19(suppl 1):S39-S46. doi: 10.1016/S1078-5884(00)80004-0

16. Tan MLM, Feng J, Gordois A, Wong ESD. Lower extremity amputation prevention in Singapore: economic analysis of results. Singapore Med J. 2011;52:662-668.

17. Yost ML. The cost of critical limb ischemia (CLI). Why is the disease so costly? The Sage Group. 2019.

18. Agency for Healthcare Research and Quality. Healthcare cost and utilization project: HCUP query: analysis of ICD-10 procedure codes for major amputation. Accessed June 2020. http://www.hcup.ahrq.gov/

19. Yost ML. Screening for PAD in high-risk patient groups. The Sage Group. 2016.

20. Martinez RA, Shnayder M, Parreco J, et al. Nationally representative readmission factors in patients with claudication and critical limb ischemia. Ann Vasc Surg. 2018;52:96-107. doi: 10.1016/j.avsg.2018.03.011

21. Kolte D, Kennedy KF, Shishehbor MH, et al. Thirty-day readmissions after endovascular or surgical therapy for critical limb ischemia: analysis of the 2013 to 2014 nationwide readmissions databases. Circulation. 2017;136:167-176. doi: 10.1161/CIRCULATIONAHA.117.027625

22. Reinecke H, Unrath M, Freisinger E, et al. Peripheral arterial disease and critical limb ischaemia: still poor outcomes and lack of guideline adherence. Eur Heart J. 2015;36:932-938. doi: 10.1093/eurheartj/ehv006

23. Armstrong EJ, Chen DC, Westin GG, et al. Adherence to guideline-recommended therapy is associated with decreased major adverse cardiovascular events and major adverse limb events among patients with peripheral arterial disease. J Am Heart Assoc. 2014;3:e000697. doi: 10.1161/JAHA.113.000697

24. Chung J, Timaran DA, Modrall JG, et al. Optimal medical therapy predicts amputation-free survival in chronic critical limb ischemia. J Vasc Surg. 2013;58:972-980. doi: 10.1016/j.jvs.2013.03.050

25. Henry AJ, Hevelone ND, Belkin M, Nguyen LL. Socioeconomic and hospital-related predictors of amputation for critical limb ischemia. J Vasc Surg. 2011;53:330-339.e1. doi: 10.1016/j.jvs.2010.08.077

26. Allie DE, Hebert CJ, Lirtzman MD, et al. Critical limb ischemia: a global epidemic. A critical analysis of current treatment unmasks the clinical and economic costs of CLI. EuroIntervention. 2005;1:75-84.

27. Goodney PP, Travis LL, Nallamothu BK, et al. Variation in the use of lower extremity vascular procedures for critical limb ischemia. Circ Cardiovasc Qual Outcomes. 2012;5:94-102. Published correction appears in Circ Cardiovasc Qual Outcomes. 2012;5:e27. doi: 10.1161/CIRCOUTCOMES.111.962233

28. CardioVascular Coalition. The Amputation Reduction and Compassion (ARC) Act. Accessed April 12, 2021. https://cardiovascularcoalition.com/the-amputation-reduction-and-compassion-arc-act