title: A pilot study of CXCL8 levels in crystal proven gout patients during allopurinol treatment and their association with cardiovascular disease.
abstract: OBJECTIVE
  Gout is associated with cardiovascular diseases, and systemic inflammation has a role in this. CXCL8 (interleukin-8) levels were increased in synovial fluid of gout patients, and in serum in gout patients irrespective of their disease activity. We hypothesized that the well-known cardiovascular protective effects of allopurinol could be related to effects of this drug on CXCL8 levels.
  
  
  METHODS
  Patients with a crystal proven gout diagnosis, who newly started allopurinol treatment, were included in this prospective cohort study. After evaluation at baseline for cardiovascular diseases, tophi, uric acid, CRP and CXCL8 serum levels, patients were followed for changes in uric acid and CXCL8 levels. A subgroup analysis was performed in 10 patients with the longest follow-up period and at least 4 assessments of serum uric acid and CXCL8.
  
  
  RESULTS
  Sixty patients were included, and patients known with cardiovascular diseases at baseline had significantly higher CXCL8 and uric acid levels (P<0.01). In the whole group, median CXCL8 levels had not decreased after a median (IQR) follow-up of 27 (12-44) weeks (P=0.66). In the subgroup analysis in 9 out of 10 patients, CXCL8 levels showed a slight decrease, sometimes after an initial increase after a median (IQR) follow-up of 51 (45-60) weeks.
  
  
  CONCLUSIONS
  This pilot study indicates that higher CXCL8 levels were associated cardiovascular diseases in gout patients. Short-term use of allopurinol does not decrease CXCL8 levels in gout patients, but longer use possibly does. Further studies are warranted to establish the potential mechanisms of treatment and effects on CXCL8 levels.
authors.affiliation: Department of Rheumatology, Rijnstate Hospital, PO Box 9555, 6800 Arnhem, TA, The Netherlands. Electronic address: l.b.e.kienhorst@umcutrecht.nl.
authors.forename: Laura
authors.initials: L
authors.lastname: Kienhorst
authors.affiliation: Department of Primary and Community Care, Radboud University Medical Center, PO Box 9101, 6500 Nijmegen, HB, The Netherlands; Department of Clinical Research, Rijnstate Hospital, PO Box 9555, 6800 Arnhem, TA, The Netherlands.
authors.forename: Hein
authors.initials: H
authors.lastname: Janssens
authors.affiliation: Department of Rheumatology and Clinical Immunology, Laboratory of Translational Immunology, PO Box 85500, 3508 Utrecht, GA, The Netherlands; Department of Immunology, University Medical Center Utrecht, PO Box 85500, 3508 Utrecht, GA, The Netherlands.
authors.forename: Timothy
authors.initials: T
authors.lastname: Radstake
authors.affiliation: Scientific Institute for Quality of Healthcare, Radboud University Medical Center, PO Box 9101, 6500 Nijmegen, HB, The Netherlands.
authors.forename: Piet
authors.initials: P
authors.lastname: van Riel
authors.affiliation: Department of Rheumatology and Clinical Immunology, Laboratory of Translational Immunology, PO Box 85500, 3508 Utrecht, GA, The Netherlands.
authors.forename: Johannes
authors.initials: J
authors.lastname: Jacobs
authors.affiliation: Department of Medical Microbiology and Immunology, Rijnstate Hospital, PO Box 9555, 6800 Arnhem, TA, The Netherlands.
authors.forename: Elly
authors.initials: E
authors.lastname: van Koolwijk
authors.affiliation: Department of Clinical Research, Rijnstate Hospital, PO Box 9555, 6800 Arnhem, TA, The Netherlands; Department of Medical Microbiology and Immunology, Rijnstate Hospital, PO Box 9555, 6800 Arnhem, TA, The Netherlands.
authors.forename: Ellen
authors.initials: E
authors.lastname: van Lochem
authors.affiliation: Department of Rheumatology, Rijnstate Hospital, PO Box 9555, 6800 Arnhem, TA, The Netherlands.
authors.forename: Matthijs
authors.initials: M
authors.lastname: Janssen
mesh_terms: D000328:Adult; D000493:Allopurinol / Q000627:therapeutic use*; D015415:Biomarkers / Q000097:blood; D002318:Cardiovascular Diseases / Q000097:blood / Q000453:epidemiology*; D016022:Case-Control Studies; D015331:Cohort Studies; D005260:Female; D006073:Gout / Q000097:blood* / Q000188:drug therapy* / Q000453:epidemiology / Q000503:physiopathology; D006074:Gout Suppressants / Q000627:therapeutic use*; D006801:Humans; D015994:Incidence; D016209:Interleukin-8 / Q000097:blood*; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D011379:Prognosis; D011446:Prospective Studies; D012016:Reference Values; D018570:Risk Assessment; D018709:Statistics, Nonparametric; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; D006074:Gout Suppressants; D016209:Interleukin-8; D000493:Allopurinol
keywords: Allopurinol; CXCL8; Cardiovascular disease; Gout; Inflammation; Uric acid