Medically unexplained symptoms and somatoform disorders: prevalence, course and comorbidity. : An eleven year general population study in Norway.

• Published in: Journal of Psychosomatic Research
• Main Author: Leiknes, Kari Ann
• Other Authors: Arnstein Finset, Torbjørn Moum and Inger Sandanger
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: 2007
• Subjects: VDP::710; Lofoten; Norway
• Online Access: http://hdl.handle.net/10852/28570; http://urn.nb.no/URN:NBN:no-15804

Somatoform disorders (SDs) according to present classifications (ICD-10/DSM-IV) are characterized by “medically unexplained symptoms” (MUSs), i.e. physical symptoms that cannot be fully explained by any detectable medical condition, substance or alcohol abuse. A main aim of this thesis is to contribute to the ongoing classification debate of SDs. An adult general population sample of 605 respondents from Oslo and Lofoten were interviewed with the Composite International Diagnostic Interview somatoform section in 1990. In 2001, 421 (70% response rate) were interviewed again. An additional random sample of 1,247 individuals was also interviewed in 2001. MUSs are extensively forgotten over time. Diagnostic stability for current SDs is 42%, and for lifetime SDs 33%. Except for a small group (mainly young women) at risk for chronicity, prognosis of MUS-pain is good. Six-month prevalence rate for current SDs with severe functional impairment is 10%. Comorbidity with anxiety/depression is 45% and with musculoskeletal disorders 43%. New classification of SDs should be based on current symptomatology and symptoms of anxiety/depression present if SDs are to be classified as mental disorders.