Assessment of patients with fibromyalgia syndrome using the BASDAI questionnaire: correlation with symptoms and potential clinical utility in a single-center study.

INTRODUCTION

Fibromyalgia (FM) is a chronic, generalized pain syndrome with symptoms that may overlap with those of axial spondyloarthritis, making differential diagnosis challenging. Since the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) relies on patient-reported outcomes that may partially reflect FM symptoms, we aimed to assess its ability to distinguish patients with FM syndrome from healthy controls and to evaluate its potential clinical utility.

METHODS

We investigated 58 adult patients diagnosed with FM and 23 age- and sex-matched healthy controls, in whom inflammatory diseases were excluded. Data were collected on activity-related factors, BASDAI, the Fibromyalgia Impact Questionnaire (FIQ), and the Symptom Severity Scale (SSS). We analyzed the correlation between BASDAI and symptom severity in patients with FM. The receiver operating characteristic (ROC) analysis was used to determine whether BASDAI differentiates between FM patients and healthy controls.

RESULTS

Patients with FM demonstrated higher scores in tender points, selected FIQ domains, and the SSS compared to controls. They also scored higher in all BASDAI components, with 91.4% of FM patients scoring ≥ 4 points, versus only 13% of controls (p < 0.001). BASDAI showed strong positive correlations with key fibromyalgia symptoms (pain, fatigue, stiffness) assessed by the FIQ. We observed a strong positive correlation between BASDAI and SSS scores (r = 0.88, p < 0.001, for all participants). ROC analysis revealed that BASDAI had relatively high diagnostic accuracy in distinguishing FM from controls, despite the small number of control subjects, with a sensitivity of 84.48% and specificity of 95.65% at a cutoff of > 4.45 points (likelihood ratio 19.43).

CONCLUSIONS

BASDAI may be a helpful additional tool for evaluating patients with FM. In individuals without inflammatory conditions, a high BASDAI score can suggest the presence of FM and help to differentiate them from healthy controls. Key Points • Patients with fibromyalgia syndrome (FM) had significantly higher BASDAI scores compared to healthy controls. • BASDAI strongly correlated with fibromyalgia symptom severity, including pain, fatigue, and stiffness. • ROC analysis showed BASDAI had high accuracy (AUC, sensitivity 84.48%, specificity 95.65%) in distinguishing FM from controls. • BASDAI may be helpful in identifying FM in individuals without inflammatory diseases.