title: Evaluation of the effect of statin use on the acenocoumarol and phenprocoumon maintenance dose.
abstract: BACKGROUND
  Statins and coumarins are prescribed in combination on a regular basis. Some case reports suggested that statins might affect the dose requirements of coumarins. The aim of the study was to investigate whether acenocoumarol and phenprocoumon maintenance doses are influenced by statin use.
  
  
  METHODS
  The Pre-EU-PACT database was used, which contains information on 471 acenocoumarol and 624 phenprocoumon users. The influence of individual statins on the acenocoumarol and phenprocoumon maintenance dose was investigated by comparing unadjusted and adjusted mean differences of the maintenance dose between statin and non-statin users.
  
  
  RESULTS
  Lower adjusted acenocoumarol dose requirements were observed for patients using atorvastatin, simvastatin, pravastatin, and rosuvastatin. These patients had a reduction in adjusted mean acenocoumarol maintenance dose of 0.11, 0.29, 0.38, and 0.69 mg/day, respectively, compared with a mean adjusted dose of 2.60 mg/day for the patients not using a statin. There was no significant effect of statin use on unadjusted and adjusted phenprocoumon maintenance dose (p=0.23 and p=0.35, respectively).
  
  
  CONCLUSIONS
  Mean acenocoumarol maintenance dosages were decreased when acenocoumarol is co-administered with the different statins. Statin use does not affect phenprocoumon maintenance doses significantly.
authors.affiliation: sion of Pharmacoepidemiology and Clinical Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands.
authors.forename: Rianne M F
authors.initials: RM
authors.lastname: van Schie
authors.forename: Talitha I
authors.initials: TI
authors.lastname: Verhoef
authors.forename: Saskia B
authors.initials: SB
authors.lastname: Boejharat
authors.forename: Tom
authors.initials: T
authors.lastname: Schalekamp
authors.forename: Judith A M
authors.initials: JA
authors.lastname: Wessels
authors.forename: Saskia
authors.initials: S
authors.lastname: le Cessie
authors.forename: Frits R
authors.initials: FR
authors.lastname: Rosendaal
authors.forename: Felix J M
authors.initials: FJ
authors.lastname: van der Meer
authors.forename: Anthonius
authors.initials: A
authors.lastname: de Boer
authors.forename: Anke-Hilse
authors.initials: AH
authors.lastname: Maitland-van der Zee
mesh_terms: D000074:Acenocoumarol / Q000008:administration & dosage*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000008:administration & dosage*; D004347:Drug Interactions; D005260:Female; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D010644:Phenprocoumon / Q000008:administration & dosage*
chemical_list: D000925:Anticoagulants; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D000074:Acenocoumarol; D010644:Phenprocoumon