title: Reduced creatinine clearance is associated with early development of subcutaneous tophi in people with gout.
abstract: BACKGROUND
  Although typically a late feature of gout, tophi may present early in the course of disease. The aim of this study was to identify factors associated with the presence of early tophaceous disease.
  
  
  METHODS
  People with gout for <10 years were prospectively recruited, and had a comprehensive clinical assessment including examination for subcutaneous tophi. The clinical factors independently associated with the presence and number of tophi were analyzed using regression models.
  
  
  RESULTS
  Of the 290 participants, there were 47 (16.2%) with clinically apparent tophi. In univariate analysis, those with tophi were older, were more frequently taking diuretics and colchicine prophylaxis, and had lower creatinine clearance. The association between the presence of tophi and creatinine clearance was strongest in those with creatinine clearance ≤30 ml/min. In logistic regression analysis, creatinine clearance ≤30 ml/min was associated with the presence of tophi, even after adjusting for ethnicity, corticosteroid use, colchicine use and diuretic use (multivariate adjusted odds ratio 7.0, p = 0.005). Participants with tophi reported higher frequency of gout flares, pain scores, patient global assessment scores, and HAQ scores.
  
  
  CONCLUSIONS
  The presence of tophi is associated with more symptomatic disease in people with gout for <10 years. Creatinine clearance is independently associated with early presentation of subcutaneous tophi.
authors.affiliation: Bone and Joint Research Group, Department of Medicine, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd, Grafton, New Zealand. n.dalbeth@auckland.ac.nz.
authors.forename: Nicola
authors.initials: N
authors.lastname: Dalbeth
authors.forename: Meaghan E
authors.initials: ME
authors.lastname: House
authors.forename: Anne
authors.initials: A
authors.lastname: Horne
authors.forename: William J
authors.initials: WJ
authors.lastname: Taylor
mesh_terms: D000328:Adult; D000368:Aged; D003404:Creatinine / Q000097:blood*; D005260:Female; D005549:Foreign-Body Reaction / Q000209:etiology*; D006073:Gout / Q000150:complications* / Q000378:metabolism; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D014527:Uric Acid / Q000378:metabolism*
chemical_list: D014527:Uric Acid; D003404:Creatinine