Anterior segment parameters and corneal specular microscopy findings in rheumatoid arthritis

Aim: To compare the anterior segment parameters and specular microscopy findings between patients with Rheumatoid arthritis(RA) and healthy controls.Material and Methods: In this prospective study, 55 patients diagnosed with RA and age and matched 55 control subjects without anysystemic diseases were enrolled. Central corneal thickness (CCT), corneal endothelial cell density (cells/mm2) (ECD), percentage ofhexagonal cells of corneal endothelial cells ( HEX), and cell size variability (CV%) of endothelial cells were measured using noncontactspecular microscopy (CEM-530 Specular Mıcroscope, NIDEK ).Anterior chamber depth (ACD), Axial Length (AL), white to white limbus length and keratometry were measured using an ocularbiometry system. In all patients of RA group, disease activity severity was assessed with The Disease Activity Score in 28 jointsdiseases activity score (DAS28 rate).Results: There were statistically significant differences between RA patients and control subjects regarding ACD (3.06±0.43 vs3.24±0.31; p: 0.001), white to white limbus length (11.63±0.45 vs 11.76±0.38; p: 0.02), CV% (35.49±5.96 vs 32.02±5.22, p: 0.001)and hexagonality (67.31±4.66 vs 71.35±11.02; p: 0.001). In correlation analysis, there was a negative correlation between diseaseperiods and both ACD and CCT; while there was a negative correlation with the number of cells and endothelial cell density and DAS28 score.Conclusion: Although there was not a significant difference regarding endothelial cell density values in RA group compared withhealthy controls; there was a negative correlation between the disease activity and endothelial cell density. Moreover, CV% wassignificantly higher and hexagonality % was significantly lower in RA group; indicating the endothelial damage and increase in theexpected compensatory response.Further, larger studies are warranted to define the exact pathological mechanisms and clinical outcomes of this corneal endothelialdamage in RA patients.