title: Outcomes of infrainguinal bypass determined by age in the Vascular Study Group of New England.
abstract: BACKGROUND
  Many believe extremes of age correlate with poorer outcomes in treatment for lower extremity peripheral arterial disease (PAD). We hypothesized that the youngest patients would have significantly poorer outcomes compared with older cohorts due to the precocious nature of their PAD.
  
  
  METHODS
  We studied all patients in the Vascular Study Group of New England database undergoing infrainguinal bypass for PAD between 2003 and 2013. Age was grouped by <50 years, 50 to 79 years, and ≥80 years. Our primary outcomes were 1-year freedom from a major adverse limb event (MALE), defined as ipsilateral amputation or need for secondary intervention, and amputation-free survival. A second analysis was performed to analyze the subgroup of patients aged <50 years with critical limb ischemia (CLI), which included a Cox regression model to determine risk factors for MALE or death at 1 year.
  
  
  RESULTS
  Of 5265 patients who were treated with infrainguinal bypass for PAD, 324 (6.2%) were aged <50 years. The mean age was 44.6 years, and 66.4% were male. The proportion of African Americans was significantly higher in the youngest age group (<50 years: 6.8% vs 50-79 years: 3.5%, P = .002; vs ≥80 years: 3.5%, P = .013). More bypasses were done for claudication than acute limb ischemia in patients aged <50 years (33.3% vs 11.4%). More vein grafts were used vs prosthetic (<50 years: 72.1% vs 50-79 years: 65.9%, P = .024; vs ≥80 years: 62.6%, P = .002). Fewer concomitant proximal procedures were performed compared with the older groups (<50 years: 37.7% vs 50-79 years: 51.1%, P < .001; vs ≥80 years: 39.5%, P = .045). More young patients returned to the operating room within their initial hospitalization for early graft thrombosis (<50 years: 5.6% vs 50-79 years: 2.9%, P = .001; vs ≥80 years: 2.4%, P = .009) and revision (<50 years: 4.7% vs 50-79 years: 2.2%, P = .012; vs ≥80 years: 1.4%, P = .002) compared with the older patients. Overall, MALE-free survival was similar across age groups (P = .323), as were patency and amputation rates. When considering only patients with CLI, MALE-free survival in the youngest patients was again similar (P = .171) but with significantly more major amputations at 1 year (P = .022).
  
  
  CONCLUSIONS
  For patients aged <50 undergoing infrainguinal bypass surgery, this large series demonstrates similar overall medium-term graft-related outcomes compared with older cohorts. Further, although the youngest patients with CLI have similar MALEs, their amputation rates are higher than in older cohorts.
authors.affiliation: Division of Vascular Surgery, Lancaster General Health Physicians Surgical Group, Lancaster, Pa. Electronic address: meghandermody@gmail.com.
authors.forename: Meghan
authors.initials: M
authors.lastname: Dermody
authors.affiliation: Department of Surgery, Tufts Medical Center, Boston, Mass.
authors.forename: Christopher
authors.initials: C
authors.lastname: Homsy
authors.affiliation: Section of Vascular Surgery, Dartmouth Hitchcock Medical Center, Lebanon, NH.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Section of Vascular Surgery, Dartmouth Hitchcock Medical Center, Lebanon, NH.
authors.forename: Philip P
authors.initials: PP
authors.lastname: Goodney
authors.affiliation: Division of Vascular Surgery, The Cardiovascular Center, Tufts Medical Center, Boston, Mass.
authors.forename: James M
authors.initials: JM
authors.lastname: Estes
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000671:Amputation, Surgical; D016009:Chi-Square Distribution; D016638:Critical Illness; D016208:Databases, Factual; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007383:Intermittent Claudication / Q000175:diagnosis / Q000401:mortality / Q000601:surgery*; D007511:Ischemia / Q000175:diagnosis / Q000401:mortality / Q000601:surgery*; D053208:Kaplan-Meier Estimate; D023821:Limb Salvage; D035002:Lower Extremity / Q000098:blood supply*; D008297:Male; D008875:Middle Aged; D009511:New England; D058729:Peripheral Arterial Disease / Q000175:diagnosis / Q000401:mortality / Q000601:surgery*; D016016:Proportional Hazards Models; D012086:Reoperation; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D014656:Vascular Surgical Procedures / Q000009:adverse effects / Q000401:mortality