Late-Onset AxSpA: Understanding Variations in Disease Presentation

11/13/2024

A recent study suggests that patients with late-onset axial spondyloarthritis (axSpA) are more likely to have peripheral arthritis. They are also less likely to test positive for the human leukocyte antigen B27 (HLA-B27) or to report a family history of spondyloarthritis.

Symptoms of axSpA usually begin before age 45. However, some evidence suggests that axSpA may sometimes appear later in life as a distinct “late-onset” form (lo-axSpA). Since this late-onset form is not well documented, researchers in this study aimed to assess how common lo-axSpA is and to identify any differences between patients with late-onset axSpA and those with the more typical early-onset form (eo-axSpA).

Using data from Portugal’s national rheumatic disease registry, scientists examined differences between patients with early- and late-onset axSpA. They included 2,165 adults diagnosed with axSpA and recorded age of symptom onset, defining late-onset axSpA (lo-axSpA) as symptoms starting at age 45 or older. The study compared both groups based on demographics (such as age and smoking status), key disease features, symptoms, and types of treatment. A statistical model was then used to identify which factors were most strongly associated with lo-axSpA, taking gender into account.

Out of the total 2165 patients, 273 (13%) had symptom onset at age 45 or older. and were therefore labeled as lo-axSpA. Lo-axSpA patients were less likely to test positive for the HLA-B27 genetic marker, have a family history of axSpA, experience inflammatory back pain, or have eye inflammation (uveitis). They were more likely to experience peripheral arthritis, which occurs in joints such as knees, ankles, shoulders, and wrists.

These results suggest that, while uncommon, lo-axSpA does exist as a unique form of the disease, with slightly different symptoms and genetic associations. At the same time, the researchers acknowledge that recall bias—errors in participants’ recollections of past symptoms—could have influenced the accuracy of results. It’s also possible that this late-onset form may not be a separate form of disease–it may simply reflect the challenges of recognizing a less typical disease presentation. Further studies are needed to clarify these distinctions.

References:

• Annals of the Rheumatic Diseases – Prevalence and Clinical Characteristics of Late-Onset Axial Spondyloarthritis: Results from a Multicentre Nationwide Study
• Spondylitis Association of America – Diagnosis of Ankylosing Spondylitis
• Spondylitis Association of America – Podcast Episode 63 | Spondyloarthritis and Aging: Navigating Changes in Later Years
• Cureus – Characteristics of Late-Onset Spondyloarthritis: Data from the Moroccan Registry of Biological Therapies in Rheumatic Diseases