Exploring the Interaction Between HLA-B27 and Other Risk Factors of Valvular Heart Disease in Axial Spondyloarthritis

HLA-B27 plays a critical role in axial spondyloarthritis (axSpA). Valvular heart disease (VHD) is a life-threatening extra-articular manifestation of axSpA. The evidence for the association between HLA-B27 and VHD in axSpA is still scarce and controversial. In this study, we aim to mainly explore the association of HLA-B27 and VHD in axSpA, and the interaction between HLA-B27 and other risk factors of VHD in axSpA.

We analyze cross-sectional data of axSpA patients from 2016 to 2022 in Shenzhen Second People's Hospital. Multivariable logistic regression models were fitted to evaluate the association between HLA-B27 and VHD in axSpA patients. When discovering the interaction between HLA-B27 and sex and disease duration, we made stratified analyses.

Included were 444 axSpA patients with echocardiography during inpatient admission. Males were 299, and females were 145. In the adjusted model of multivariable logistic analysis, only age increased the risk of VHD (OR 1.054; 95% CI 1.021-1.087). To detect interactions between HLA-B27 and other variables that affected the outcome of VHD, sex and categorical disease duration were found to interact with HLA-B27 after being adjusted by age (p < 0.05). In sex-stratified analysis, male patients with HLA-B27 increased the risk of VHD (OR 11.2; 95% CI 1.40-89.36) after being adjusted by age. In stratified analysis of disease duration, over 24 months of duration increased the risk of VHD (OR 5.86; 95% CI 1.27-27.07).

Our study provided evidence that age was the only independent risk factor for VHD in axSpA. HLA-B27 interacted with sex and disease duration to increase the risk of VHD in axSpA patients.