title: Hypersensitivity and hyperalgesia in somatoform pain disorders.
abstract: OBJECTIVE
  In psychiatry, pain disorders not explained by structural lesions have been classified for decades as somatoform pain disorders, the underlying concept being somatization. In a parallel move, somatic medicine has defined an expanding group of similar pain disorders, known as functional pain syndromes. Functional pain syndromes are characterized by enhanced pain sensitivity. The aim of our study was to investigate the proportion of patients with somatoform pain disorders who also meet the criteria of functional pain syndromes and the extent to which patients with somatoform pain disorders also show enhanced pain sensitivity.
  
  
  METHODS
  Data on pain sensitivity in 120 hospitalized patients were obtained by means of two algometric methods. The group of patients with somatoform pain disorders was further divided into two subsets: patients with and those without a co-diagnosis of a functional pain syndrome. Patients with nociceptive pain served as control group.
  
  
  RESULTS
  Of the 120 in-patients selected, 67 fulfilled the criteria of a somatoform pain disorder of which 41 (61%) also met the co-diagnosis of a functional pain syndrome. Patients with somatoform pain disorder differed from controls in that they showed enhanced pain sensitivity, irrespective of whether a functional pain syndrome was concomitantly present (P<.001).
  
  
  CONCLUSIONS
  Somatoform pain disorders show considerable overlap with functional pain syndromes, including enhanced pain sensitivity. This suggests the relevance of integrating somatosensory aspects of pain into a modified understanding of somatoform pain disorders.
authors.affiliation: Department of General Internal Medicine, Division of Psychosomatic Medicine, Inselspital, Bern University Hospital, CH-3010 Bern, Switzerland; Department of Clinical Research, University of Bern, 3012 Bern, Switzerland. Electronic address: nik.egloff@bluewin.ch.
authors.forename: Niklaus
authors.initials: N
authors.lastname: Egloff
authors.affiliation: Institute of Medical Biostatistics, Epidemiology, and Informatics, University Medical Centre of Johannes Gutenberg University, D-55131 Mainz, Germany.
authors.forename: Rafael J A
authors.initials: RJ
authors.lastname: Cámara
authors.affiliation: Department of General Internal Medicine, Division of Psychosomatic Medicine, Inselspital, Bern University Hospital, CH-3010 Bern, Switzerland; Department of Clinical Research, University of Bern, 3012 Bern, Switzerland.
authors.forename: Roland
authors.initials: R
authors.lastname: von Känel
authors.affiliation: Department of General Internal Medicine, Division of Psychosomatic Medicine, Inselspital, Bern University Hospital, CH-3010 Bern, Switzerland.
authors.forename: Nicole
authors.initials: N
authors.lastname: Klingler
authors.affiliation: Department of General Internal Medicine and Clinic for Orthopedics, Inselspital, Bern University Hospital, CH-3010 Bern, Switzerland.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Marti
authors.affiliation: Department of General Internal Medicine, Division of Psychosomatic Medicine, Inselspital, Bern University Hospital, CH-3010 Bern, Switzerland; Department of Clinical Research, University of Bern, 3012 Bern, Switzerland.
authors.forename: Marie-Louise Gander
authors.initials: ML
authors.lastname: Ferrari
mesh_terms: D000328:Adult; D000368:Aged; D015897:Comorbidity; D005260:Female; D006801:Humans; D006930:Hyperalgesia / Q000175:diagnosis / Q000453:epidemiology*; D006967:Hypersensitivity / Q000175:diagnosis / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D059226:Nociceptive Pain / Q000175:diagnosis / Q000453:epidemiology; D010146:Pain / Q000175:diagnosis / Q000453:epidemiology*; D013001:Somatoform Disorders / Q000175:diagnosis / Q000453:epidemiology*
keywords: Algometry; Central sensitivity syndromes; Functional pain syndromes; Hyperalgesia; Somatoform pain