Primary fibromyalgia syndrome--an outcome study.

Seventy-two patients (65 F, 7 M; mean age 52, range 18-81 years) fulfilling criteria for primary fibromyalgia syndrome (PFS) were reviewed at a mean of 4 years (range 1.5-6) following diagnosis. Ninety-seven per cent still had symptoms typical of PFS (60% worse, 26% better than at presentation); 85% had multiple hyperalgesic tender sites and still fulfilled criteria for PFS; 8% had more limited, and 7% had no tender sites at review. Many had significant disability (median score 1.0, range 0-2.75, on the Health Assessment Questionnaire; median 2, range 1-3 on the Steinbrocker index) and 92% scored highly (> 12) on the Hospital Anxiety and Depression index. In no patient did screening investigations reveal development of inflammatory, metabolic, endocrine or muscle disease. This study confirms a poor outcome for PFS patients and association with often marked functional disability and high levels of anxiety and depression. Contrary to one previous study there was no evidence that PFS predates the onset of other disease.