Fibromyalgia: its prevalence in haemodialysis patients and its relationships with clinical and laboratory parameters.

OBJECTIVE Our aim was to determine the prevalence of fibromyalgia syndrome (FS) in chronic haemodialysis (HD) patients and to identify possible links between FS and various clinical and laboratory parameters. METHODS We studied 122 chronic HD patients and 89 healthy age- and sex-matched controls, classified according to the American College of Rheumatology (ACR) classification criteria for FS. Age, sex, causes of renal failure, length of time on dialysis and marital status were recorded, and questions were asked about symptoms related to FS. All subjects completed the Fibromyalgia Impact Questionnaire (FIQ). Laboratory data obtained in the preceding 6 months were re-evaluated. RESULTS Nine (7.4%) of the 122 HD patients and four of the 89 control subjects (4.5%) fulfilled the ACR criteria for definite FS (P = 0.56). The mean ages of the subjects who had definite FS and those who did not were similar. Most of the subjects diagnosed with definite FS were female (11 out of 13). The HD patients had higher FIQ scores than the controls, regardless of FS diagnosis. Among the HD patients, those with definite FS had a significantly higher mean FIQ score than all the other HD patients combined. In the all HD patients group, fatigue, irritable bowel syndrome and personal histories of depression were correlated with FS, whereas duration of HD, aetiology of renal failure, laboratory parameters and hepatitis B or C virus infection were not. CONCLUSION The prevalence of FS appeared to be similar in chronic HD patients and the general population; also, FS-related symptoms appear to be similar in HD patients and the general population who have FS. No laboratory parameter was correlated with frequency of FS.