Lower odds of prevalent vertebral fractures with b/tsDMARD use among rheumatoid arthritis patients in clinical remission: a retrospective observational study

OBJECTIVES: This study investigated serum pentosidine levels as an advanced glycation end product (AGE)-related marker of bone matrix deterioration and examined the association between b/tsDMARD use and prevalent vertebral fractures in patients with RA in clinical remission. METHODS: Seventy-six patients with RA in clinical remission (DAS28-CRP < 2.3) were included. Serum pentosidine, bone turnover markers, and bone mineral density (BMD) were assessed. Lateral thoracolumbar spine radiographs were available for 51 patients, and prevalent vertebral fractures were evaluated using artificial-intelligence-assisted morphometry, with final physician confirmation. Multivariable regression analyses evaluated factors associated with serum pentosidine levels and prevalent vertebral fractures. RESULTS: Patients receiving b/tsDMARDs had lower serum pentosidine levels (P = 0.004) despite comparable BMD and bone turnover marker profiles. In multivariable linear regression, DAS28-ESR was associated with serum pentosidine levels (β = 0.00581, P = 0.011), while b/tsDMARD use showed a non-significant trend toward lower serum pentosidine levels (β = - 0.00544, P = 0.091). Vertebral fractures were numerically less common in patients receiving b/tsDMARDs (2/19 [10.5%] vs 11/32 [34.4%]). In logistic regression, older age was associated with higher odds of prevalent vertebral fractures (odds ratio 1.211 per year, 95% CI 1.074-1.439; P < 0.001), while b/tsDMARD use was associated with lower odds (odds ratio 0.144, 95% CI 0.015-0.841; P = 0.030). CONCLUSIONS: In patients with RA in clinical remission, b/tsDMARD use was associated with lower odds of prevalent vertebral fractures. Residual inflammation, reflected by DAS28-ESR and serum pentosidine levels, may be relevant to skeletal fragility beyond BMD. Key Points • Lower serum pentosidine levels were observed in b/tsDMARD-treated patients, whereas DAS28-ESR was independently associated with serum pentosidine levels in multivariable analysis. • In patients with rheumatoid arthritis in clinical remission, b/tsDMARD use was associated with lower odds of prevalent vertebral fractures. • Residual inflammation and bone matrix deterioration may be related to skeletal fragility beyond bone mineral density.