title: A Meta-analysis of Long-term Mortality and Associated Risk Factors following Lower Extremity Amputation.
abstract: BACKGROUND
  A majority of patients undergoing lower limb amputations have diabetes or peripheral artery disease. Despite improvements in care, there remains a substantial perioperative mortality associated with these procedures. Less well-defined is the mortality risk to these patients going forward, once outside the perioperative period. The aim of this systematic review is to summarize and pool the available data to determine the long-term mortality associated with amputation in the diabetic and peripheral vascular patient, as well as to define specific factors associated with increased mortality risk.
  
  
  METHODS
  Four databases were searched from January 2005 through July 2015 using the Medical Subject Headings terms "amputation," "lower extremity," and "mortality." Inclusion criteria were observational and cohort studies where ≥50% of amputations were attributable to diabetic or vascular etiologies. Final article inclusion was approved by reviewer consensus. Bias was assessed with the Joanna Briggs Institute Critical Appraisal Tool for cohort studies.
  
  
  RESULTS
  Of the 365 unique records screened, 43 abstracts and 21 full articles were reviewed and 16 studies ultimately included. The overall mortality rate was 47.9%, 61.3%, 70.6%, and 62.2% at 1-, 2-, 3- and 5-year follow-up, respectively. In addition to diabetes and peripheral vascular disease, comorbid factors associated with at least a 2-fold increased mortality were coronary artery disease, cerebrovascular disease, renal dysfunction, American Society of Anesthesiologists class ≥4, dementia, and nonambulatory status. Surgical factors, including higher amputation level and need for staged surgery with up-front guillotine amputation, were also correlated with increased mortality.
  
  
  CONCLUSIONS
  The overall mortality rate after primary lower limb amputation in the diabetic and peripheral vascular population is substantial, and should not be underestimated when making decisions regarding limb salvage. Similar to patients undergoing revascularization, comorbid conditions associated with higher mortality should be optimized before surgery whenever possible.
authors.affiliation: Department of Surgery, Division of Vascular Surgery and Endovascular Interventions, Columbia University Medical Center, New York, NY. Electronic address: jrs9016@nyp.org.
authors.forename: Jordan R
authors.initials: JR
authors.lastname: Stern
authors.affiliation: Department of Rehabilitation and Regenerative Medicine, Columbia University Medical Center, New York, NY.
authors.forename: Christopher K
authors.initials: CK
authors.lastname: Wong
authors.affiliation: Department of Rehabilitation and Regenerative Medicine, Program in Physical Therapy, Columbia University, New York, NY.
authors.forename: Marina
authors.initials: M
authors.lastname: Yerovinkina
authors.affiliation: Department of Rehabilitation and Regenerative Medicine, Program in Physical Therapy, Columbia University, New York, NY.
authors.forename: Stephanie J
authors.initials: SJ
authors.lastname: Spindler
authors.affiliation: Department of Rehabilitation and Regenerative Medicine, Program in Physical Therapy, Columbia University, New York, NY.
authors.forename: Ashley S
authors.initials: AS
authors.lastname: See
authors.affiliation: Department of Rehabilitation and Regenerative Medicine, Program in Physical Therapy, Columbia University, New York, NY.
authors.forename: Samira
authors.initials: S
authors.lastname: Panjaki
authors.affiliation: Department of Rehabilitation and Regenerative Medicine, Program in Physical Therapy, Columbia University, New York, NY.
authors.forename: Sarah L
authors.initials: SL
authors.lastname: Loven
authors.affiliation: Department of Rehabilitation and Regenerative Medicine, Program in Physical Therapy, Columbia University, New York, NY.
authors.forename: Rick F
authors.initials: RF
authors.lastname: D'Andrea
authors.affiliation: Department of Surgery, Division of Vascular Surgery and Endovascular Interventions, Columbia University Medical Center, New York, NY.
authors.forename: Roman
authors.initials: R
authors.lastname: Nowygrod
mesh_terms: D000368:Aged; D000671:Amputation, Surgical / Q000009:adverse effects / Q000401:mortality*; D015897:Comorbidity; D003925:Diabetic Angiopathies / Q000175:diagnosis / Q000401:mortality / Q000601:surgery*; D005260:Female; D006801:Humans; D035002:Lower Extremity / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D016491:Peripheral Vascular Diseases / Q000175:diagnosis / Q000401:mortality / Q000601:surgery*; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome