title: Diurnal excretion of urinary cortisol, cortisone, and cortisol metabolites in chronic fatigue syndrome.
abstract: OBJECTIVE
  The aim of this study was to obtain comprehensive information on basal hypothalamic-pituitary-adrenal (HPA) axis activity in chronic fatigue syndrome (CFS) patients who were not affected by medication or comorbid psychiatric disorder likely to influence the HPA axis.
  
  
  METHODS
  Steroid analysis of urine collections from 0600 to 2100 h at 3-h intervals in CFS patients and in controls.
  
  
  RESULTS
  Urinary free cortisol and cortisone concentrations showed a significant normal diurnal rhythm, but levels were lower across the cycle in CFS. In contrast, while urinary cortisol metabolites also showed a normal diurnal rhythm, levels were not significantly different between the CFS and controls at any time. Derived metabolite ratios were similar in both groups.
  
  
  CONCLUSIONS
  This study provides further evidence for reduced basal HPA axis function in patients with CFS, based on lower free cortisol and cortisone levels, but this is not corroborated by cortisol metabolite data. The difference between these measures cannot be explained by an altered timing of the diurnal rhythm.
authors.affiliation: Department of Clinical Biochemistry, Guy's, King's and St Thomas' School of Medicine, Bessemer Road, SE5 9RS London, UK. jerjes@kcl.ac.uk
authors.forename: Walid K
authors.initials: WK
authors.lastname: Jerjes
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Peters
authors.forename: Norman F
authors.initials: NF
authors.lastname: Taylor
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Wood
authors.forename: Simon
authors.initials: S
authors.lastname: Wessely
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Cleare
mesh_terms: D000328:Adult; D002940:Circadian Rhythm / Q000502:physiology*; D003348:Cortisone / Q000652:urine*; D015673:Fatigue Syndrome, Chronic / Q000503:physiopathology* / Q000652:urine; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000652:urine*; D006889:Hydroxycorticosteroids / Q000652:urine*; D007030:Hypothalamo-Hypophyseal System / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D010913:Pituitary-Adrenal System / Q000503:physiopathology*; D012016:Reference Values; D013760:Tetrahydrocortisol / Q000652:urine; D013761:Tetrahydrocortisone / Q000652:urine
chemical_list: D006889:Hydroxycorticosteroids; D013761:Tetrahydrocortisone; D013760:Tetrahydrocortisol; D003348:Cortisone; D006854:Hydrocortisone