title: [Is there an association between fibromyalgia and an increase in comorbidity: neoplastic and cardiovascular diseases, infections and mortality?].
abstract: OBJECTIVE
  To determine whether fibromyalgia (FM) is associated with an increase in comorbidity (infections, neoplastic and cardiovascular disease) as well as with an increase in mortality.
  
  
  METHODS
  We performed a systematic review. Using a sensitive search strategy, all studies published in PubMed (from 1961), Embase (from 1991), Cochrane Library Plus and abstracts of rheumatology congresses (ACR and EULAR, from 1999) until May 2005 were selected. Cohort, descriptive and comparative studies were selected. The results of the search were screened through a review of the titles and abstracts.
  
  
  RESULTS
  Of the 562 references retrieved by the search, 33 potentially relevant studies were selected. Patients with FM showed greater comorbidity and medical resource use than did the general population and patients with other rheumatic diseases. FM was more frequent in hospitalized patients and in the context of HIV and hepatitis C infections. Some studies found a high risk of developing cancer in FM patients. Several studies found an increased mortality rate in FM, mainly due to cancer and suicide.
  
  
  CONCLUSIONS
  Despite the high comorbidity and medical resource use in FM, there is no evidence that this entity is associated with an increase in comborbidity due to cardiovascular disease or infections. The association between FM and HIV and hepatitis C virus infections suggests a possible relationship between FM and chronic viral infection. Patients with chronic generalized pain may have an increased risk of developing cancer. FM may also carry an increased risk of accidental death and death from cancer.
authors.affiliation: Unidad de Reumatología. Hospital General de Mérida. España.
authors.forename: E
authors.initials: E
authors.lastname: Chamizo-Carmona