Objective To investigate the expression of long non-coding RNA (lncRNA) X-inactive specific transcript (XIST) and microRNA-410-3p (miR-410-3p) in serum of patients with rheumatoid arthritis (RA), and their correlation with bone mineral density (BMD) and bone metabolism indicators.

Methods A total of 109 RA patients were selected as research subjects. After measuring BMD using dual-energy X-ray absorptiometry (DXA), they were divided into osteoporosis group (53 cases) and non-osteoporosis group (56 cases). BMD at different sites and serum levels of lncRNA XIST, miR-410-3p, and bone metabolism indicators β-C-terminal telopeptide of type I collagen (β-CTX), parathyroid hormone (PTH), osteocalcin (OC), osteoprotegerin (OPG), and N-terminal propeptide of type Ⅰ procollagen (PⅠNP)were compared between the two groups. Pearson correlation analysis was used to analyze the correlation between lncRNA XIST and miR-410-3p, as well as their correlation with BMD and bone metabolism indicators. Logistic regression analysis was used to screen the influencing factors for osteoporosis in RA patients.

Results Compared with the non-osteoporosis group, the osteoporosis group had lower BMD at the lumbar spine, femoral neck, greater trochanter, and Ward's triangle area, higher levels of OPG, β-CTX, and lncRNA XIST, and lower levels of miR-410-3p, with statistically significant differences (P < 0.05). There were no statistically significant differences in PTH, OC, and PⅠNP levels between the two groups (P>0.05). Pearson correlation analysis showed that serum lncRNA XIST levels were negatively correlated with miR-410-3p levels (r=-0.435, P < 0.001). Serum lncRNA XIST levels were negatively correlated with BMD at the lumbar spine, femoral neck, greater trochanter, and Ward's triangle area (P < 0.05), and positively correlated with OC levels (P < 0.05). Serum miR-410-3p levels were positively correlated with BMD at the lumbar spine, femoral neck, greater trochanter, and Ward's triangle area (P < 0.05), and negatively correlated with OC levels (P < 0.05). Multivariate logistic regression analysis showed that BMD, lncRNA XIST, and miR-410-3p were all independent influencing factors for osteoporosis in RA patients (P < 0.05).

Conclusion LncRNA XIST expression is upregulated in serum of RA patients with osteoporosis, while miR-410-3p expression is downregulated. They are closely related to BMD at the lumbar spine, femoral neck, greater trochanter, and Ward's triangle area, as well as OC levels of bone metabolism indicators.