Evaluation of the Association Between Axial Length and Cup-to-Disc Ratio Among Non-Glaucomatous Hypertensive Patients

Abstract

Background: Cup-to-disc ratio (CDR) is a key clinical parameter for optic nerve head assessment, yet physiological variation may be influenced by ocular biometry and systemic factors such as hypertension. Axial length (AL) can modify optic disc morphology and may complicate interpretation of CDR during glaucoma screening in hypertensive patients without glaucoma. Objective: To determine the association between axial length and cup-to-disc ratio among non-glaucomatous hypertensive patients. Methods: An observational cross-sectional study was conducted on 94 hypertensive patients aged 18–70 years at Al-Shifa Eye Clinic, Ali Pur Chatha. Eligible participants had normal intraocular pressure (<21 mmHg) and AL between 21–26 mm. Blood pressure was assessed using a calibrated sphygmomanometer, AL was measured using A-scan ultrasonography, and vertical CDR was assessed by slit-lamp biomicroscopy with a +90D lens after dilation. Non-normality was assessed using the Kolmogorov–Smirnov test, and associations were evaluated using Spearman’s correlation with multivariable linear regression adjusting for age. Results: The cohort included 64 males (68.1%) and 30 females (31.9%), with mean age 42.19±15.71 years. Spearman’s correlation showed no significant association between AL and CDR (OD: r=0.029, p=0.778; OS: r=0.135, p=0.195). In regression models, AL did not significantly predict CDR in either eye (OD: B=0.000, p=0.963; OS: B=0.011, p=0.097). Conclusion: Axial length was not significantly associated with cup-to-disc ratio in non-glaucomatous hypertensive patients within the studied biometric range