Evidence Summary
An increased risk of mortality following a major lower limb amputation is consistently reported in prospective and retrospective studies from the UK and the rest of the world, with mortality rates ranging from 30-50% at 1 year 1-3 and 60-77% at 5 years 1 3 4. A prospective review of referrals to a regional rehabilitation centre in the UK identified that 57.1% underwent amputation for peripheral vascular disease, 31.4% due to diabetes, 7.6% due to trauma and 3.8% due to tumours 5. They found an increased risk of mortality in diabetics, with 52% mortality at 3 years in those with diabetes compared with 33% overall. The reported rates of mortality are higher in those studies excluding amputations due to trauma and tumours, as these patients tend to be younger and have fewer co-morbidities. In addition, the rates of mortality are lower in those that are fitted with a prosthesis, a decision often based upon the presence of medical co-morbidities and frailty.
Those undergoing a lower limb amputation are known to have a high number of co-morbidities. A retrospective study at a regional UK vascular centre looked at those undergoing an above knee amputation and found that 58% of their cohort had diabetes mellitus, 39% had chronic kidney disease, 35% had heart failure and 13% had COPD 6. Similar rates of diabetes and chronic kidney disease were reported in a retrospective study from the USA looking specifically at those undergoing amputation for peripheral vascular disease, with 83% also having hypertension and 51% having hyperlipidaemia 2. 63 of their 391 patients had a subsequent contralateral amputation during their follow up period. Physical activity should be encouraged in lower limb amputees, as regular physical activity is known to positively influence many of these co-morbidities. In type 2 diabetics that have undergone a lower limb amputation, the risk of major cardiac events is increased if they are non-concordant with physical activity recommendations, in addition to smoking cessation, anti-platelet therapy and dietary change 7.
Amputees spend more time in low-intensity activities than the general population and have high levels physical inactivity 8 9. The presence of sarcopenia on abdominal MRI within 1 year of a lower limb amputation for diabetes predicts an increased risk of mortality, with a mortality rate of 60.7% in those with sarcopenia and 36.4% without 4. The risk of sarcopenia, a loss of skeletal muscle mass and strength, is known to be reduced by regular physical activity, including cardiovascular and strengthening exercises, so may reduce mortality in this cohort.
Quality of evidence
Grade A – High quality
Strength of recommendation
Grade 1 – Strong
Conclusion
Regular physical activity should be recommended to most people following a major lower limb amputation to help reduce their increased risk of mortality and the high number of co-morbidities.
References
- Jones WS, Patel MR, Dai D, et al. High mortality risks after major lower extremity amputation in Medicare patients with peripheral artery disease. American Heart Journal 2013;165(5):809-+. doi: 10.1016/j.ahj.2012.12.002
- Shah SK, Bena JF, Allemang MT, et al. Lower Extremity Amputations: Factors Associated With Mortality or Contralateral Amputation. Vascular and Endovascular Surgery 2013;47(8):608-13. doi: 10.1177/1538574413503715
- Fortington LV, Geertzen JHB, van Netten JJ, et al. Short and Long Term Mortality Rates after a Lower Limb Amputation. European Journal of Vascular and Endovascular Surgery 2013;46(1):124-31. doi: 10.1016/j.ejvs.2013.03.024
- Kim YK, Lee HS, Ryu JJ, et al. Sarcopenia increases the risk for mortality in patients who undergo amputation for diabetic foot. Journal of Foot and Ankle Research 2018;11 doi: 10.1186/s13047-018-0274-1
- Singh RK, Prasad G. Long-term mortality after lower-limb amputation. Prosthetics and Orthotics International 2016;40(5):545-51. doi: 10.1177/0309364615596067
- Kennedy G, McGarry K, Bradley G, et al. All-Cause Mortality Amongst Patients Undergoing Above and Below Knee Amputation in a Regional Vascular Centre within 2014-2015. The Ulster medical journal 2019;88(1):30-35.
- Shalaeva EV, Saner H, Janabaev BB, et al. Tenfold risk increase of major cardiovascular events after high limb amputation with non-compliance for secondary prevention measures. European Journal of Preventive Cardiology 2017;24(7):708-16. doi: 10.1177/2047487316687103
- Desveaux L, Goldstein RS, Mathur S, et al. Physical Activity in Adults with Diabetes Following Prosthetic Rehabilitation. Canadian Journal of Diabetes 2016;40(4):336-41. doi: 10.1016/j.jcjd.2016.02.003
- Pepin ME, Akers KG, Galen SS. Physical activity in individuals with lower extremity amputations: a narrative review. Physical Therapy Reviews 2018;23(2):77-87. doi: 10.1080/10833196.2017.1412788