Fibromyalgia symptom scale (FSS) is a useful guide to fibromyalgia diagnosis.

Abstract

Aim: The ACR 2016 Revisions to the 2010/2011 fibromyalgia diagnostic criteria have clarified fibromyalgia diagnosis and research classification. Main components of the criteria are the Widespread Pain Index (WPI) and the Symptom Severity Scale (SSS). These can be added to produce the Fibromyalgia Severity Scale (FSS) which provides a measure of fibromyalgia severity. The FSS has also been used to approximate diagnostic status, with 92-96% of patients with a score >= 12 satisfying criteria in international studies. The aim is to investigate the usefulness of the FSS as a surrogate diagnostic tool in an Australian population. Method(s): Consecutive patients seen in the Monash Fibromyalgia Clinic were assessed clinically, including assessment of the ACR 2016 revised diagnostic criteria. FSS and Fibromyalgia Impact Questionnaire (FIQ) scores were calculated. FSS was compared to 2016 diagnostic criteria status. Result(s): 424 patients were included (91.5% female, mean age 45.12 years, symptom duration 10.61 years). Of these, 408 (96.2%) had an FSS score >= 12. All patients who met 2016 diagnostic criteria had an FSS of >=12. Of patients who had a FSS of >= 12, 20 (4.9%) did not meet 2016 diagnostic criteria. Patients with a FSS >= 12 had significantly more associated central sensitivity conditions (p = 0.046) and more tenderness (p = 0.000) than those with a score below 12. There was no difference in age or symptom duration. The FSS correlated with FIQ score, pain, fatigue, sleep problems, anxiety and depression (p <= 0.000). Conclusion(s): The FSS is a useful continuous scale measure of fibromyalgia symptom burden, and when used with a cut point of 12, can serve as an approximation of diagnostic criteria status in an Australian population.