title: Association between renal failure and foot ulcer or lower-extremity amputation in patients with diabetes.
abstract: OBJECTIVE
  The objective of this study was to evaluate the association between foot ulcers (DFU) and lower-extremity amputation (LEA) and chronic kidney disease (CKD) in patients with diabetes. RESARCH DESIGN AND METHODS: This was a retrospective cohort study of individuals enrolled between 2002 and 2006 who were aged > or =35 years, had a history of diabetes, and were cared for in general practice. The physicians participated in The Health Information Network of the U.K.
  
  
  RESULTS
  The presence of DFU or LEA and estimated glomerular filtration rate (eGFR) were evaluated in 90,617 individuals with a median time of observation of 2.4 years. Of these individuals 378 had an LEA and 2,619 had a DFU. CKD (eGFR <60 ml/min per 1.73 m(2)) was noted in 23,350 (26%) individuals in our cohort. For the development of DFU compared with our reference group (group 1 [eGFR > or =60 ml/min per 1.73 m(2)]), the hazard ratio (HR) for group 2 (eGFR > or =30 and <60 ml/min per 1.73 m(2)) was 1.85 (95% CI 1.71-2.01) and for group 3 (eGFR <30 ml/min per 1.73 m(2)) was 3.92 (3.23-4.75) (all P < 0.001). For LEA, the HR for group 2 was 2.08 (1.68-2.58) and for group 3 was 7.71 (5.29-11.26) (all P < 0.001).
  
  
  CONCLUSIONS
  In this observational study, there is a strong association between stage of CKD and DFU or LEA that is probably not just related to the presence of peripheral arterial disease. Individuals with even moderate CKD (eGFR <60 ml/min per 1.73 m(2)) have an increased risk for DFU and LEA.
authors.affiliation: Department of Dermatology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA. margo@mail.med.upenn.edu
authors.forename: David J
authors.initials: DJ
authors.lastname: Margolis
authors.forename: Ole
authors.initials: O
authors.lastname: Hofstad
authors.forename: Harold I
authors.initials: HI
authors.lastname: Feldman
mesh_terms: D000671:Amputation, Surgical / Q000706:statistics & numerical data*; D044383:Black People; D015331:Cohort Studies; D017719:Diabetic Foot / Q000150:complications / Q000601:surgery*; D003928:Diabetic Nephropathies / Q000150:complications*; D004739:England; D016523:Foot Ulcer / Q000150:complications / Q000601:surgery*; D005919:Glomerular Filtration Rate; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications; D015999:Multivariate Analysis; D012189:Retrospective Studies; D014852:Wales