Disease activity, health status and quality of life in patients with ankylosing spondylitis associated with fibromyalgia

Abstract

Annotation. Ankylosing spondylitis (AS) and fibromyalgia (FM) are often comorbid pathological conditions, and the presence of FM, which characterized by the complexity of diagnosis and treatment, may be one of the factors delaying the diagnosis of AS. FM can also complicate the interpretation of disease activity, assessment of pain and the choice of adequate anti-inflammatory therapy, which makes it essential to study the impact of this comorbidity on the clinical course of AS. The study aimed to evaluate the indicators of disease activity, health, and quality of life of patients with AS associated with FM. One hundred forty-three patients with AS (81.8% of men) aged 42.1±11.3 years (M ± σ) were examined. The diagnosis of AS was established according to modified New York criteria (1984), and the diagnosis of FM – by the criteria of mACR2010. FM detected in 49 (34.3%) individuals. Indicators of disease activity (ASDAS-ESR, BASDAI), functional status (BASMI, BASFI), quality of life and health (ASQoL, ASAS HI/EF, HAQ), fatigue, sleep disorders, depressive and cognitive disorders (MAF, PSQI, HAM-D, MMSE) was determined. The study was conducted in compliance with bioethical standards. Statistical processing of the results was performed using IBM Statistics SPSS 22. Patients with concomitant FM showed higher rates of disease activity by BASDAI and poorer functional ability by BASFI and BASMI (by 30.2%; 53.2% and 33.2%, p<0.01), by ASDAS-ESR (by 11,5%, p<0.05). Among patients with FM, individuals with very high disease activity (BASDAI≥6.0), significant functional disorders (BASFI≥4.0 and BASMI≥4.0) were more likely than among patients without FM (1.97; 1,69 and 1.73 times, p <0.001, respectively). Patients with AS with FM showed worse health and quality of life indicators for ASQoL, HAQ and ASAS HI (65.2%; 34.7% and 26.4%, p<0.001). Moderate and severe fatigue (MAF ≥ 20), sleep disorders (PSQI ≥ 5) and depressive disorders (HAM-D ≥ 8) were in 75.5%; 68.1% and 60.6% of patients without FM and in 98%; 100% and 98% (p<0.001) of patients with FM. There are direct correlations between the severity of polysymptomatic distress and the BASDAI, BASFI and ASAS HI indices (r = 0.52; 0.57 and 0.42, p<0.001). So, patients with AS with FM characterized by higher disease activity, more insufficient functional ability and lower quality of life.