We observed that hip joint involvement, which indicates more severe disease, was related to a higher risk of discontinuing TNF-α inhibitors, which was in line with a study by Jeong et al. [25] Additionally, complete spinal ankylosis and a higher grade of sacroiliitis were related to a higher risk of the non-persistence of TNF-α blockers in previous reports [27,28]. This evidence concerns the gene TNF and ankylosis.