title: Medical comorbidities but not interventions adversely affect survival in patients with intermittent claudication.
abstract: OBJECTIVE
  Intermittent claudication (IC) is common and associated with decreased survival. While patients with IC infrequently progress to critical limb ischemia (CLI), many elect to pursue intervention initially or during follow-up. However, controversy exists as to whether intervention in patients with IC adversely impacts survival or limb salvage. The purpose of this study was to characterize patient demographics and comorbidities with respect to differences in survival and limb salvage among patients who elect no intervention (NI) vs those electing immediate intervention (II) or delayed intervention (DI) for IC.
  
  
  METHODS
  Patients referred to a university practice for limb ischemia were identified via a query of the electronic medical record from 2007 to 2011. Patients with prior lower extremity interventions or CLI were excluded. IC patients were classified according to intervention: NI during follow-up, II, and DI. Patient demographics, Charlson morbidity index, survival, and reintervention rates were analyzed.
  
  
  RESULTS
  A total of 262 of 1320 patients met inclusion criteria. Thirty patients with possible IC were believed to have nonarterial related symptoms. Study patients included 132 with NI, 62 with II, and 38 with DI. DI patients were younger and less frequently diabetic (median age, 65.5 years, 63.5 years, 58.0 years; P = .002; diabetes, 43.2%, 39.5%, 22.6%; P = .02 for NI, II, and DI, respectively). NI patients had higher Charlson comorbidity scores (P < .05). Hypertension, hyperlipidemia, and diabetes were associated with decreased survival in all groups (P < .05). Median survival was greatest for DI patients and least for NI patients (NI 92 months, II 95 months, DI 143 months; log-rank = .015). Primary patency of interventions at 1 and 5 years were equal for II and DI patients (1 year, II 80% vs DI 79%; 5 years, II 45% vs DI 50%; P = .9). Reintervention was common with rates similar between the II and DI groups (P > .05). Four of 38 DI patients required minor amputation for progression to CLI. There were no major amputations in any group.
  
  
  CONCLUSIONS
  Progression to CLI is uncommon in IC. Survival of claudicants is decreased by diabetes, hypertension, and hyperlipidemia but not by intervention for IC. Reintervention is common in treated IC patients but no different among those undergoing II and DI. Intervention did not lead to major amputation. II or DI in IC patients does not affect survival or major amputation.
authors: Department of Surgery, Division of Vascular Surgery, Oregon Health and Science University, Portland, Ore.
authors: Marcus R
authors: MR
authors: Kret
authors: Kenneth H
authors: KH
authors: Perrone
authors: Amir F
authors: AF
authors: Azarbal
authors: Erica L
authors: EL
authors: Mitchell
authors: Timothy K
authors: TK
authors: Liem
authors: Gregory J
authors: GJ
authors: Landry
authors: Gregory L
authors: GL
authors: Moneta
mesh_terms: D000368:Aged; D015897:Comorbidity; D048909:Diabetes Complications / Q000453:epidemiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006949:Hyperlipidemias / Q000453:epidemiology*; D006973:Hypertension / Q000453:epidemiology*; D007383:Intermittent Claudication / Q000453:epidemiology* / Q000601:surgery; D023821:Limb Salvage / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D015996:Survival Rate / Q000639:trends; D014481:United States / Q000453:epidemiology