Ankylosing Spondylitis May Increase VTE Risk: Study
Ankylosing Spondylitis (AS) can prove to be a major risk factor for the development of venous thromboembolism (VTE), reveals a new meta-analysis study, published in Frontiers in Immunology journal by Quan H. and colleagues. The meta-analysis reveals that in patients with AS, the incidence of VTE, deep vein thrombosis, or pulmonary embolism remains higher.
There have been long-standing connections between autoimmune and chronic inflammatory conditions and VTE based on the spectrum of either systemic inflammation or endothelial damage and coagulation dysfunctions. Yet the link between AS and VTE remains unclear. The study systematically searched PubMed, Embase, Cochrane Library, and Web of Science from database commencement until June 2025. It comprised six observational studies that fulfilled specific inclusion criteria. It analyzed data from a total of 601585 participants. Two authors independently selected and extracted data.
They used the RoBINS-I assessment method to determine risk of bias. It calculated and combined adjusted hazard ratios (HRs) with their 95% confidence intervals (CIs) with RevMan Computer Software Version 5.3. They registered its protocol in PROSPERO (CRD420251107387) after completion and made a GRADE assessment of its body of evidence.
Key findings:
The pooled analysis demonstrated that ankylosing spondylitis was associated with a 47% higher risk of VTE compared with controls (HR = 1.47; 95% CI, 1.22–1.77; P < 0.0001), although the overall certainty of evidence was rated as very low due to the observational nature of the data.
Subgroup analyses further clarified this association, showing a consistent increase in risk across different thrombotic outcomes.
When individual VTE components were examined, AS was associated with a 57% increased risk of overall VTE (HR = 1.57; 95% CI, 1.26–1.96; P < 0.0001).
The risk of deep vein thrombosis was increased by 62% (HR = 1.62; 95% CI, 1.16–2.26; P = 0.005), while the risk of pulmonary embolism was elevated by 24% (HR = 1.24; 95% CI, 1.06–1.45; P = 0.008).
Sensitivity analyses confirmed the robustness of these findings, and no major publication bias was evident on funnel plot inspection.
Current evidence suggests that ankylosing spondylitis is associated with an increased risk of venous thromboembolism, though further mechanistic studies are needed to clarify and interpret findings from observational data. Although these findings support closer clinical awareness of thrombotic risk in AS, further prospective and mechanistic studies are needed to confirm causality and determine whether targeted prevention strategies may improve outcomes in this population.
Reference:
Hu, Q., Mei, M., Liu, R., & Zhang, Q. (2025). The association between ankylosing spondylitis and the risk of venous thromboembolism: a meta-analysis. Frontiers in immunology, 16, 1670965. https://doi.org/10.3389/fimmu.2025.1670965
