Ankylosing spondylitis (AS) remains difficult to diagnose before irreversible damage to sacroiliac joint is noticeable. Circulating microRNAs have demonstrated to serve as diagnostic tools for several human diseases. Here, we analysed plasma microRNAs to identify potential AS biomarkers. Higher expression levels of microRNA (miR)-146a-5p, miR-125a-5p, miR-151a-3p and miR-22-3p, and lower expression of miR-150-5p, and miR-451a were found in AS versus healthy donors. Interestingly, higher miR-146a-5p, miR-125a-5p, miR-151a-3p, miR-22-3p and miR-451a expression was also observed in AS than psoriatic arthritis patients. The areas under the curve, generated to assess the accuracy of microRNAs as diagnostic biomarkers for AS, ranged from 0.614 to 0.781; the six-microRNA signature reached 0.957. Bioinformatics analysis revealed that microRNAs targeted inflammatory and bone remodeling genes, underlying their potential role in this pathology. Indeed, additional studies revealed an association between these six microRNAs and potential target proteins related to AS pathophysiology. Furthermore, miR-146a-5p, miR-125a-5p and miR-22-3p expression was increased in active versus non-active patients. Moreover, miR-125a-5p, miR-151a-3p, miR-150-5p and miR-451a expression was related to the presence of syndesmophytes in AS patients. Overall, this study identified a six-plasma microRNA signature that could be attractive candidates as non-invasive biomarkers for the AS diagnosis, and may help to elucidate the disease pathogenesis.

To evaluate quality of life (QoL) in patients with axial spondyloarthritis (axSpA) and its association with disease activity, functionality, structural damage, and spinal mobility, using patient-reported outcomes. This was an observational, cross-sectional, and single-center study in which 100 consecutive patients with axSpA were included. We obtained from all patients' sociodemographic data and values related to disease activity, functionality, structural damage, mobility, and quality of life. The Ankylosing Spondylitis Quality of Life Questionnaire (ASQoL) was considered as the primary outcome. Pearson r statistic, Student's T test, and univariate and multivariate linear regressions were performed to relate ASQoL with the studied covariates. Mean ASQoL score in all patients was 4.02 ± 2.81, with statistically significant differences between male and female (3.61 ± 2.80 vs. 4.83 ± 2.70). Patients with high disease activity (measured by the ASAS-endorsed Disease Activity Score, ASDAS > 2.1) showed higher mean score in ASQoL than those with low disease activity (ASDAS ≤ 2.1) (3.21 ± 0.74 vs. 1.43 ± 0.43, p < 0.001). ASQoL presented a significant linear correlation with BASDAI, BASFI, and ASDAS (r > 0.60). However, disease duration was not significantly correlated with ASQoL. Finally, the 68.9% of the ASQoL variability (R = 0.689) was determined by BASDAI, BASFI, and mSASSS, presenting mSASSS a negative regression coefficient (- 0.035). In our study, the impairment of QoL was mainly associated with disease activity (BASDAI) and worsening of functionality (BASFI). However, there is an inverse relationship between the worsening of QoL and structural damage. In addition, disease duration does not seem to influence the patient's welfare.