Central corneal thickness in a Jordanian population and its association with different types of Glaucoma: cross-sectional study

Background Central corneal thickness (CCT) has long been implicated to affect glaucoma predisposition. Several reports have identified that thinner CCT is a risk factor for open-angle glaucoma, and that CCT can be very variable between different ethnic groups. In this study, we aim to identify the relation between CCT and different glaucoma parameters in different types of glaucoma in an Arabian ethnicity. Methods We classified our participants into four main groups: primary open-angle glaucoma (POAG), primary angle-closure glaucoma (PACG), pseudoexfoliative glaucoma (PXFG), and a control group. We obtained demographics, intraocular pressure (IOP), cup to disc ratio (CDR), visual field mean deviation (MD) and pattern standard deviation (PSD), CCT, and retinal nerve fiber layer (RNFL) thickness for each participant. Results We included A total of 119 eyes with glaucoma, including POAG (54 eyes), PXFG (31 eyes) and PACG (34 eyes), we also included 57 control eyes. We found that PACG eyes have the thinnest CCT. Mean measurements of CCT for our groups were: 538.31 μm (SD = 36.30) in eyes with POAG, 544.45 μm (SD = 28.57) in eyes with PXFG, 506.91 μm (SD = 34.55) in eyes with PACG and 549.63 μm (SD = 42.9) in the control group. We found that CCT is significantly correlated with CDR ( p = 0.012, r = − 0.231), MD ( p < 0.001, r = 0.327),and RNFL thickness ( p = .007, r = .283). Conclusion In Arabian ethnicity, PACG patients have the thinnest CCT compared to other types of glaucoma, namely POAG and PXFG. We demonstrated that glaucomatous eyes with thinner corneas will probably have more advanced glaucomatous optic neuropathy. Our results emphasize the importance of taking ethnicity into account upon glaucoma management.