Background
Peripheral artery disease (PAD) is an atherosclerotic cardiovascular condition affecting the lower limbs. A classic symptom of PAD is intermittent claudication (IC), which precipitates on exertion and is relieved with rest. 1 Supervised exercise programmes (SEPs) are first line treatments for patients with IC.2,3 Despite the benefits of exercise, there are inconsistencies between guidelines regarding the recommended level of prescribed claudication pain. The aim of this commentary is to highlight the limitations of current guidance which will lead to variability in care.
The National Institute of Health and Care Excellence (NICE), 4 American Heart Association 5 and British Association of Sport and Exercise Sciences 6 recommend exercising to maximal claudication pain. Supporting this, an early meta-analysis showed walking to near maximal pain to be most beneficial at improving maximal walking and pain-free walking distances. Indicating that greater amounts of ischaemia induced may produce greater haemodynamic and metabolic adaptations. 7 Furthermore, high-intensity walking, eliciting moderate–severe ischaemic leg symptoms, was superior to low-intensity without ischaemic leg symptoms. 8
Conversely, the American College of Sports Medicine 3 and Exercise and Sports Science Australia 9 suggest moderate pain is most beneficial. A systematic review suggested mild to moderate claudication pain yields optimal results in walking distance and cardiorespiratory fitness when compared to maximal pain. 10 The conclusions were in line with the Vascular Disease Foundation and the American Association of Cardiovascular and Pulmonary Rehabilitation guidelines 11 in that lower limb exercise should be performed to a threshold of mild–moderate pain. 12
Despite the inconsistencies aforementioned, alarmingly several guidelines do not report a level of claudication pain to work towards, 10 whilst others suggest working at a speed and gradient that induces claudication pain within 3–5 min, without specifying the intensity of the pain. 11 As such, clinicians are not provided with clear guidance. A major issue is that guidelines are not fully inclusive of the evidence, as they do not consider pain-free exercise. A meta-analysis showed significant improvements in absolute and initial walking distance without inducing claudication pain. 13 A recent systematic review also suggests pain-free SEPs elicit similar improvements in walking performance and functional outcomes compared to moderate pain. 14
The missed consideration of pain-free SEPs and high claudication pain prescription may lead to poor uptake, as high claudication pain has been commonly cited as a barrier to exercise adherence and uptake of SEPs.15,16 Indeed patients taking part in a low pain SEP where 1.52 times more likely to complete the SEP than those in the high pain SEP. 16 As SEPs are the first line of treatment for patients with PAD, guidelines must ensure greater participation occurs; consequently, patient ability and preference should be considered, so it is tolerable and beneficial for all patients. 17
In conclusion, there are inconsistencies regarding the recommended level of claudication pain for clinicians to prescribe. Furthermore, there is no consideration for the evidence base regarding pain-free exercise. It is clear there is a need for a universal set of guidelines that consider optimising patient outcomes as well as uptake and adherence in relation to claudication pain. No research has directly compared maximal, pain-free and moderate claudication pain; however, trials are underway. 18
Footnotes
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding: The author(s) received no financial support for the research, authorship, and/or publication of this article.
ORCID iDs
Sally A Seed https://orcid.org/0000-0002-2717-7485
Amy E Harwood https://orcid.org/0000-0002-5745-2564
References
- 1.Fowkes FG, Rudan D, Rudan I, et al. Comparison of global estimates of prevalence and risk factors for peripheral artery disease in 2000 and 2010: a systematic review and analysis. Lancet 2013; 382: 1329–1340. DOI: 10.1016/s0140-6736(13)61249-0 [DOI] [PubMed] [Google Scholar]
- 2.Lane R, Harwood A, Watson L, et al. Exercise for intermittent claudication. Cochrane Database Syst Rev 2017; 12: Cd000990. DOI: 10.1002/14651858.CD000990.pub4 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Riebe D, Ehrman JK, Liguori G, et al. ACSM’s guidelines for exercise testing and prescription/senior editor, Deborah Riebe ; associate editors, Jonathan K. Ehrman, Gary Liguori, Meir Magal. Tenth edition ed. Philadelphia, PA: Wolters Kluwer, 2018. [Google Scholar]
- 4.Layden J, Michaels J, Bermingham S, et al. Diagnosis and management of lower limb peripheral arterial disease: summary of NICE guidance. BMJ 2012; 345: e4947. [DOI] [PubMed] [Google Scholar]
- 5.Gerhard-Herman MD, Gornik HL, Barrett C, et al. 2016 AHA/ACC guideline on the management of patients with lower extremity peripheral artery disease: executive summary: a report of the American College of Cardiology/American Heart Association task force on clinical practice guidelines. Circulation 2017; 135: e686–e725. DOI: 10.1161/CIR.0000000000000470 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 6.Tew GA, Harwood AE, Ingle L, et al. The bases expert statement on exercise training for people with intermittent claudication due to peripheral arterial disease. The Sport and Exercise Scientist 2018. In press. [Google Scholar]
- 7.Gardner AW, Poehlman ET. Exercise rehabilitation programs for the treatment of claudication pain. A meta-analysis. JAMA 1995; 274: 975–980. [PubMed] [Google Scholar]
- 8.McDermott MM, Spring B, Tian L, et al. Effect of low-intensity vs high-intensity home-based walking exercise on walk distance in patients with peripheral artery disease: the lite randomized clinical trial. JAMA 2021; 325: 1266–1276. DOI: 10.1001/jama.2021.2536 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 9.Askew CD, Parmenter B, Leicht AS, et al. Exercise & Sports Science Australia (ESSA) position statement on exercise prescription for patients with peripheral arterial disease and intermittent claudication. Journal of Science and Medicine in Sport 2014; 17: 623–629, DOI: 10.1016/j.jsams.2013.10.251 [DOI] [PubMed] [Google Scholar]
- 10.Aboyans V, Ricco JB, Bartelink MEL, et al. 2017 ESC Guidelines on the Diagnosis and Treatment of Peripheral Arterial Diseases, in collaboration with the European Society for Vascular Surgery (ESVS): Document covering atherosclerotic disease of extracranial carotid and vertebral, mesenteric, renal, upper and lower extremity arteriesEndorsed by: the European Stroke Organization (ESO) the task force for the diagnosis and treatment of peripheral arterial diseases of the European Society of Cardiology (ESC) and of the European Society for Vascular Surgery (ESVS). Eur Heart J 2018; 39: 763–816. DOI: 10.1093/eurheartj/ehx095 [DOI] [PubMed] [Google Scholar]
- 11.Norgren L, Hiatt WR, Dormandy JA, et al. Inter-society consensus for the management of peripheral arterial disease (TASC II). J Vasc Surg 2007; 45: S5–S67. DOI: 10.1016/j.jvs.2006.12.037. [DOI] [PubMed] [Google Scholar]
- 12.Parmenter BJ, Dieberg G, Smart NA. Exercise training for management of peripheral arterial disease: a systematic review and meta-analysis. Sports Medicine 2015; 45: 231–244. DOI: 10.1007/s40279-014-0261-z [DOI] [PubMed] [Google Scholar]
- 13.Parmenter BJ, Raymond J, Dinnen P, et al. A systematic review of randomized controlled trials: walking versus alternative exercise prescription as treatment for intermittent claudication. Atherosclerosis 2011; 218: 1–12, DOI: 10.1016/j.atherosclerosis.2011.04.024 [DOI] [PubMed] [Google Scholar]
- 14.Seed SA, Harwood AE, Sinclair J, et al. A systematic review of exercise prescription in patients with intermittent claudication: does pain matter? Ann Vasc Surg 2021; 77: 315–323. DOI: 10.1016/j.avsg.2021.06.025 [DOI] [PubMed] [Google Scholar]
- 15.Harwood AE, Smith GE, Cayton T, et al. A systematic review of the uptake and adherence rates to supervised exercise programs in patients with intermittent claudication. Ann Vasc Surg 2016; 34: 280–289. DOI: 10.1016/j.avsg.2016.02.009 [DOI] [PubMed] [Google Scholar]
- 16.Lin E, Nguyen C, Thomas S. Completion and adherence rates to exercise interventions in intermittent claudication: traditional exercise versus alternative exercise – a systematic review. Eur J Prev Cardiol 2019; 26: 204748731984699. DOI: 10.1177/2047487319846997 [DOI] [PubMed] [Google Scholar]
- 17.Harwood AE, Pymer S, Ingle L, et al. Exercise training for intermittent claudication: a narrative review and summary of guidelines for practitioners. BMJ Open Sport Exerc Med 2020; 6: e000897. DOI: 10.1136/bmjsem-2020-000897 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 18.Birkett ST, Sinclair J, Seed SA, et al. Effects of exercise prescribed at different levels of claudication pain on walking performance in patients with intermittent claudication: a protocol for a randomised controlled trial. Ther Adv Cardiovasc Dis 2022; 16: 17539447221108817. DOI: 10.1177/17539447221108817 [DOI] [PMC free article] [PubMed] [Google Scholar]