How does rheumatoid arthritis affect corneal biomechanical properties?

The aim of this study was to investigate the corneal alterations occurring in rheumatoid arthritis (RA) patients compared with healthy subjects and to define the presence of biomechanical alterations in cornea accompanying dry eye disease, the most common ocular manifestation of RA. Forty-seven RA patients and 40 control cases without any known systemic or ocular diseases were included in this prospective, cross-sectional study. All subjects underwent a complete ophthalmologic examination. For the diagnosis of dry eye disease; the symptoms were asked, Break up Time and Schirmer tests were applied. The Ocular Response Analyzer (Reichert Ophthalmic Instruments, Buffalo, NY) was used to measure the biomechanical properties of the cornea. In RA group, 19 (40.4%) patients had the diagnosis of dry eye disease, but it was present in only one of the control cases (P=0.001). There was a significant difference between groups regarding the mean intraocular pressure (IOP) (P=0.04) but not the mean central corneal thickness values (P=0.56). Although there was not a statistically significant difference between RA group and control cases regarding corneal hysteresis and corneal resistance factor, IOPcc and IOPg were statistically significantly lower in RA group (P=0.03 and P=0.04, respectively). There is conflicting data in the literature about the effects of RA on the biomechanical properties of the cornea. Clinicians should be aware of these alterations since it may cause underestimated IOP readings in RA eyes. Larger prospective studies are warranted to determine the alterations on biomechanical properties of the cornea among RA patients, annually.