Abstract
Purpose :
To investigate the relationship of primary open-angle glaucoma (POAG) with corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann-correlated and corneal-compensated intraocular pressure (IOPg and IOPcc) in a large community cohort.
Methods :
The EPIC-Norfolk Eye Study is a community-based cross-sectional study based in Norfolk, UK. All 8623 participants were systematically examined and 315 were diagnosed with POAG. Logistic regression was used to test the association of POAG (0= 8234 subjects without glaucoma in either eye, 1= 315 subjects with primary open angle glaucoma in either eye) with the Ocular Response Analyzer (ORA) variables CH, CRF, IOPg, IOPcc, as well as other socio-economic and ocular factors. The higher IOPg and IOPcc and lower CH and CRF of either eyes were used to maximize the likelihood of finding an association. Variables were first examined using univariable regression, and factors that were significantly associated with POAG (p<0.05) were included in the final multivariable model. IOPg, IOPcc, CH and CRF showed collinearity and were substituted in separate multivariable models but using the same co-variates to allow the models to be directly comparable. Pseudo R2 of the four models were compared to see how much the models account for the variance of POAG.
Results :
Table 1 and 2 summarize the univariable and multivariable regression results. After adjusting for covariates, the factors significantly associated with POAG were: older age (OR 1.97-2.24/decade, p<0.0001), positive family history of glaucoma (OR 3.07-3.44, p<0.0001), higher IOPg (OR 1.08/mmHg, p<0.0001), higher IOPcc (OR 1.11/mmHg, p<0.0001), lower CH (OR 0.75/mmHg, p<0.0001), lower CRF (OR 0.86/mmHg, p<0.0001) and longer axial length (OR 1.27-1.32/mm, p<0.0001). Being pseudophakic was associated with OAG (OR 1.75-1.83, p=0.001). The pseudo R2 were higher for the models using CH (13.6%) and IOPcc (13.2%) then IOPg (11.9%) or CRF (11.2%).
Conclusions :
This study showed a significant association of POAG with higher IOPg, higher IOPcc lower CH and lower CRF. CH and IOPcc explained a greater variance of POAG than IOPg and CRF, suggesting that CH and IOPcc could be useful metrics in the management of POAG.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.