The impact of fibromyalgia on health status according to the types, demographic background and pain index.

OBJECTIVES: To compare fibromyalgia (FM) core symptoms, FM impact severity and health status between the recently defined type A and type B of fibromyalgia. To compare disease impact and health status between FM patients and non-FM chronic pain control group. Finally, to compare health related quality of life and disease symptom severity by demographic background and widespread pain index (WPI).

METHODS: A total of 284 consecutive FM patients and 96 non-FM control patients were enrolled. The information of four questionnaires including the Fibromyalgia Survey Questionnaire (FSQ), the Fibromyalgia Impact Questionnaire (FIQ), the 12-item Short Form Health Survey (SF-12) and questionnaires regarding demographic features were collected from a local FM registry.

RESULTS: Of all FM patients, 102 (94%) and 7 (6%) were type A and B, respectively. We found statistically significant differences in symptomatology, the FIQ scores and the SF-12 subscales across two type and control groups (p<0.001). However, when we compared these scores pairwise, except WPI there were no significant differences in other scores between type A and B. Also, there were no significant differences in FIQ and SF-12 scores across different age or educational status groups. Interestingly, patients with higher WPI had significantly higher FIQ (overall, symptom, and total) scores, worse PCS-12 and MCS-12 scores, and vice versa.

CONCLUSIONS: Type B constitutes a minor but important component of FM that probably has a marked impact on the patient's perceived illness severity and quality of life. Further, WPI probably is the most important single indicator of disease severity and quality of life in FM.