Age Distribution and Associated Factors of Cornea Biochemical Parameter Stress-Strain Index in Chinese Healthy Population

Abstract

Background: To investigate the new cornea biochemical parameter stress-strain index (SSI) in Chinese healthy people and the factors associated with SSIMethods: A total of 175 eyes from 175 participants were recruited in this study. Axial length was measured with the Lenstar LS-900. Pentacam was used to measure curvature of the cornea and ACV and cornea biomechanical properties were measured by corneal visualization Scheimpflug technology (Corvis ST). Student’s t-test, one-way ANOVA, univariate and multivariate linear regression were used in the statistical analysis.Results: The mean (±SD) SSI was 1.14 ± 0.22 (range, 0.66–1.78) in all subjects and affected by age significantly after age of 35 (P < 0.05). In univariate regression models, SSI did not vary with biomechanical intraocular pressure (bIOP) (P=0.989), steepest radius of anterior corneal curvature (RsF) (P=0.984) or central corneal thickness (CCT) (P=0.651). In multivariate regression models, SSI was significantly associated with age (β=0.557, P<0.001), axial length (AL) (β=-0.550, P<0.001), intraocular pressure (IOP) (β=0.377, P<0.001) and flattest radius of anterior corneal curvature (RfF) (β=0.222, P<0.001) but not with anterior chamber volume (ACV).Conclusions: SSI was increased by age after the age of 35. In addition to age, SSI and RfF, IOP is positively correlated and negatively correlated with AL.