title: Association between allopurinol use and hip fracture in older patients.
abstract: BACKGROUND
  Allopurinol reduces oxidative stress and interacts with purinergic signalling systems important in bone metabolism and muscle function. We assessed whether allopurinol use was associated with a reduced incidence of hip fracture in older people.
  
  
  METHODS
  Analysis of prospective, routinely-collected health and social care data on patients undergoing health and social work assessment in a single geographical area over a 12year period. Exposure to allopurinol was derived from linked community prescribing data, and hospitalisation for hip fracture and comorbid disease was derived from linked hospitalisation data. Fine and Gray modelling was used to model time to hip fracture accounting for the competing risk of death, incorporating previous use of allopurinol, cumulative exposure to allopurinol as a time dependent variable, and covariate adjustments.
  
  
  RESULTS
  17,308 patients were alive at the time of first social work assessment without previous hip fracture; the mean age was 73years. 10,171 (59%) were female, and 1155 (8%) had at least one exposure to allopurinol. 618 (3.6%) sustained a hip fracture, and 4226 (24%) died during a mean follow-up of 7.2years. In fully-adjusted analyses, each year of allopurinol exposure conferred a hazard ratio of 1.01 (95% CI 0.99, 1.02; p=0.37) for hip fracture and 1.00 (0.99, 1.01; p=0.47) for death. Previous use of allopurinol conferred a hazard ratio of 0.76 (0.45, 1.26; p=0.28) for hip fracture and 1.13 (0.99, 1.29; p=0.07) for death.
  
  
  CONCLUSIONS
  Greater cumulative use of allopurinol was not associated with a reduced risk of hip fracture or death in this cohort.
authors.affiliation: School of Medicine, University of Dundee, UK.
authors.forename: Ujani
authors.initials: U
authors.lastname: Basu
authors.affiliation: School of Medicine, University of Dundee, UK.
authors.forename: James
authors.initials: J
authors.lastname: Goodbrand
authors.affiliation: School of Medicine, University of Dundee, UK.
authors.forename: Marion E T
authors.initials: MET
authors.lastname: McMurdo
authors.affiliation: School of Medicine, University of Dundee, UK.
authors.forename: Peter T
authors.initials: PT
authors.lastname: Donnan
authors.affiliation: School of Medicine, University of Dundee, UK.
authors.forename: Mark
authors.initials: M
authors.lastname: McGilchrist
authors.affiliation: University of Stirling, UK.
authors.forename: Helen
authors.initials: H
authors.lastname: Frost
authors.affiliation: School of Medicine, University of Dundee, UK.
authors.forename: Jacob
authors.initials: J
authors.lastname: George
authors.affiliation: School of Medicine, University of Dundee, UK. Electronic address: m.witham@dundee.ac.uk.
authors.forename: Miles D
authors.initials: MD
authors.lastname: Witham
mesh_terms: D000368:Aged; D000493:Allopurinol / Q000009:adverse effects*; D005260:Female; D006620:Hip Fractures / Q000139:chemically induced* / Q000453:epidemiology*; D006801:Humans; D008297:Male; D016016:Proportional Hazards Models; D013997:Time Factors
chemical_list: D000493:Allopurinol
keywords: Allopurinol; Fracture; Gout; Older; Risk factor