The role of musculoskeletal ultrasound in assessment of disease activity in rheumatoid arthritis patients with fibromyalgia

Introduction

Fibromyalgia (FM) is frequently present in rheumatoid arthritis (RA) patients and this can lead to an overestimation of disease activity and consequently overtreatment. Musculoskeletal ultrasound (MSUS) can aid in evaluating synovitis for assessment of disease activity with more precision.

Aim of the work

To verify the potential role of MSUS in the assessment of disease activity in RA patients with and without FM.

Patients and methods

This study was conducted on 100 active RA patients. Disease activity score (DAS28) and clinical disease activity index (CDAI) were assessed. MSUS was assessed using the 12 joint simplified score.

Results

The 100 patients were 88 females and 12 male (F:M 7.3:1) with a mean age of 44.82 ± 11.4 years and disease duration of 6.88 ± 5.77 years. 67 RA patients had associated secondary FM and 33 did not. DAS-28 and CDAI were significantly higher in those with FM (4.99 ± 0.82 and 30.49 ± 10.59) compared to those without (4.22 ± 0.96 and 18 ± 10.68)(p < 0.001). Regarding ultrasonographic finding, no significant difference was found between those with and without FMS. DAS28 and CDAI significantly correlated (p = 0.006, p = 0.002 respectively) with grey scale ultrasound (GS-US12) in patients without FMS while DAS28 only significantly correlated with GS-US12 in those with FMS (r = 0.28, p = 0.022).

Conclusion

Secondary FM is common in RA patients and associated with a higher disease activity making it a potential influencer on the treatment strategy. MSUS can complement physical examination in the assessment of disease activity but had a limited role to delineate RA patients with FM from those without.