Impact of fibromyalgia on disease activity indices, health related quality of life and fatigue in patients with psoriatic arthritis

OBJECTIVE:To assess the frequency of fibromyalgia (FM) in patients with psoriatic arthritis (PsA) and its impact on disease activity indices, fatigue and health-related quality of life (QOL). METHODS:This cross-sectional study randomly recruited patients with PsA attending an outpatient clinic between June 2017 and December 2018. Disease activity, functional ability, fatigue, and QOL were assessed for all patients. The recruited PsA patients were screened for concomitant FM, then classified into group Ι, patients with PsA only, and group ΙI, patients with FM-PsA. The severity and impact of FM were assessed for group II patients. RESULTS:A total of 60 patients with PsA were assessed with a mean age of 49.30 ± 11.69 years, of which 43.3% were female. A total of 23 PsA patients had concomitant FM (38.3%). Patients with FM-PsA showed a statistically higher disease activity in all aspects of PsA except for C-reactive protein, swollen joint count (SJC) and dactylitis count. Patients in both groups had similar functional levels, while fatigue and QOL were statistically worse in patients with FM-PsA than in patients with PsA only. CONCLUSION:These results might highlight the importance of considering FM as a contextual factor in disease activity assessment in patients with PsA, especially in those with discrepancies in tender joint count/patient-reported outcomes vs SJC/inflammatory markers and those with persistently high disease activity indices.