title: Factors associated with future amputation among patients undergoing hemodialysis: results from the Dialysis Morbidity and Mortality Study Waves 3 and 4.
abstract: BACKGROUND
  Amputation is more common in hemodialysis patients than in the general population, but risk factors for amputation in this population have not been studied extensively.
  
  
  METHODS
  We used the US Renal Data System Dialysis Morbidity and Mortality Study Waves 3 and 4 in combination with Medicare discharge data to identify factors associated with lower-extremity amputation (excluding toe amputations) in hemodialysis patients. We used stepwise multivariable logistic regression analysis to identify variables most strongly associated with amputation within 2 years of the study start date.
  
  
  RESULTS
  Male sex, diabetes, previous diagnosis of peripheral vascular disease (PVD), mean systolic blood pressure, and elevated serum phosphorus level were associated with the outcome of amputation within 2 years of the study start date. Among patients without diabetes, a previous diagnosis of cardiac disease, longer time from initiation of dialysis therapy (vintage), and previous hospitalization for limb ischemia were associated with increased risk for future amputation.
  
  
  CONCLUSIONS
  The importance of preventing amputation in this population cannot be overemphasized. The strength of the association of amputation with PVD makes a strong case for screening all dialysis patients for this disease. The association of amputation with serum phosphorus level reported here should be explored further because this may offer an avenue for future intervention to reduce amputation rates.
authors.affiliation: Department of Medicine, Nephrology Division, University of California, San Francisco, CA 94143-0532, USA. annohare@yahoo.com
authors.forename: Ann M
authors.initials: AM
authors.lastname: O'Hare
authors.forename: Peter
authors.initials: P
authors.lastname: Bacchetti
authors.forename: Mark
authors.initials: M
authors.lastname: Segal
authors.forename: Chi-yuan
authors.initials: CY
authors.lastname: Hsu
authors.forename: Kirsten L
authors.initials: KL
authors.lastname: Johansen
mesh_terms: D000671:Amputation, Surgical / Q000639:trends; D001794:Blood Pressure; D003430:Cross-Sectional Studies; D003920:Diabetes Mellitus / Q000097:blood / Q000453:epidemiology / Q000401:mortality / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007866:Leg / Q000473:pathology / Q000601:surgery; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016491:Peripheral Vascular Diseases / Q000097:blood / Q000453:epidemiology / Q000401:mortality / Q000601:surgery; D010758:Phosphorus / Q000097:blood; D006435:Renal Dialysis / Q000009:adverse effects / Q000379:methods / Q000401:mortality; D012307:Risk Factors; D013599:Systole; D016896:Treatment Outcome
chemical_list: D010758:Phosphorus