Dry eye disease in axial spondyloarthritis: heterogeneous ocular surface dysfunction involving tear film instability and tear production from the AIDA network registry

The study examined dry eye disease in patients with axial spondyloarthritis (axSpA) and healthy controls. Patients with axSpA had significantly lower tear break-up time (niTBUT) with a mean of 7.85 seconds compared to healthy individuals (10.61 seconds). The occurrence of niTBUT below 5 seconds was a significant difference between groups, while the 10-second threshold was not discriminative. The Schirmer test showed that axSpA patients have reduced tear production with an optimal threshold of 4.5 mm. Agreement between both tests was weak. The diagnosis of axSpA was the main factor influencing severe tear film instability, although patient age also contributed to this problem. The results suggest that dry eye disease in axSpA patients involves both tear film instability and reduced tear production.