title: Urinary 6 beta-hydroxycortisol excretion in rheumatoid arthritis.
abstract: The objective was to analyse whether the activity of the cytochrome P450 isoenzyme CYP3A4 is altered by disease activity of rheumatoid arthritis (RA). Urinary 6 beta-hydroxycortisol excretion, expressed as a fraction of the urinary creatinine output, was measured in 21 patients with RA treated with three different disease-modifying anti-rheumatic drugs (DMARDs) over 24 weeks. There were no correlations between urinary 6 beta-hydroxycortisol/creatinine (6 beta-OHC/Creat) ratio and measurements of disease activity such as plasma viscosity, Ritchie articular index and early morning stiffness. In addition, the three DMARDs sulphasalazine, sodium aurothiomalate and D-penicillamine, smoking and the intake of various CYP3A4 substrates had no consistent detectable effect on the 6 beta-OHC/Creat ratio. There is no evidence that the dosage of drugs metabolized by the CYP3A4 isoenzyme needs to be adjusted for disease activity in RA.
authors.affiliation: Department of Rheumatology, CH-3010 Berne, Switzerland.
authors.forename: C
authors.initials: C
authors.lastname: Beyeler
authors.forename: B M
authors.initials: BM
authors.lastname: Frey
authors.forename: H A
authors.initials: HA
authors.lastname: Bird
mesh_terms: D000328:Adult; D000368:Aged; D018501:Antirheumatic Agents / Q000494:pharmacology; D001172:Arthritis, Rheumatoid / Q000188:drug therapy* / Q000652:urine*; D004734:Energy Metabolism / Q000502:physiology; D005260:Female; D006052:Gold Sodium Thiomalate / Q000494:pharmacology; D006801:Humans; D006854:Hydrocortisone / Q000031:analogs & derivatives* / Q000652:urine; D008297:Male; D010396:Penicillamine / Q000494:pharmacology; D012460:Sulfasalazine / Q000494:pharmacology
chemical_list: D018501:Antirheumatic Agents; D006052:Gold Sodium Thiomalate; D012460:Sulfasalazine; C001380:6 beta-hydroxycortisol; D010396:Penicillamine; D006854:Hydrocortisone