I thought this had been posted before, but I can't find it anywhere... Undiagnosed and comorbid disorders in patients with presumed chronic fatigue syndrome. Mariman A, Delesie L, Tobback E, Hanoulle I, Sermijn E, Vermeir P, Pevernagie D, Vogelaers D. J Psychosom Res. 2013 Nov;75(5):491-6. doi: 10.1016/j.jpsychores.2013.07.010. Epub 2013 Aug 20. Full paper: http://www.sciencedirect.com/science/article/pii/S0022399913002766 If the above link takes you to the jpsychores website instead of the ScienceDirect website, then (to access the full paper) click on "Access this article on ScienceDirect" (top-right of the jpsychores webpage.) Abstract only: http://www.ncbi.nlm.nih.gov/pubmed/24182640 http://www.jpsychores.com/article/S0022-3999(13)00276-6/abstract Abstract OBJECTIVE: To assess undiagnosed and comorbid disorders in patients referred to a tertiary care center with a presumed diagnosis of chronic fatigue syndrome (CFS). METHODS: Patients referred for chronic unexplained fatigue entered an integrated diagnostic pathway, including internal medicine assessment, psychodiagnostic screening, physiotherapeutic assessment and polysomnography+multiple sleep latency testing. Final diagnosis resulted from a multidisciplinary team discussion. Fukuda criteria were used for the diagnosis of CFS, DSM-IV-TR criteria for psychiatric disorders, ICSD-2 criteria for sleep disorders. RESULTS: Out of 377 patients referred, 279 (74.0%) were included in the study [84.9% female; mean age 38.8years (SD 10.3)]. A diagnosis of unequivocal CFS was made in 23.3%. In 21.1%, CFS was associated with a sleep disorder and/or psychiatric disorder, not invalidating the diagnosis of CFS. A predominant sleep disorder was found in 9.7%, 19.0% had a psychiatric disorder and 20.8% a combination of both. Only 2.2% was diagnosed with a classical internal disease. In the total sample, a sleep disorder was found in 49.8%, especially obstructive sleep apnea syndrome, followed by psychophysiologic insomnia and periodic limb movement disorder. A psychiatric disorder was diagnosed in 45.2%; mostly mood and anxiety disorder. CONCLUSIONS: A multidisciplinary approach to presumed CFS yields unequivocal CFS in only a minority of patients, and reveals a broad spectrum of exclusionary or comorbid conditions within the domains of sleep medicine and psychiatry. These findings favor a systematic diagnostic approach to CFS, suitable to identify a wide range of diagnostic categories that may be subject to dedicated care.