Multi-dimensional analysis of factors influencing intraocular pressure in preschool children

Objective: To investigate the distribution of intraocular pressure(IOP) and the associated influencing factors in preschool children. Methods: A retrospective analysis was performed on the refractive error, IOP, axial length, corneal curvature, and other ocular biometric parameters of 6248 preschool children to explore the relationships between IOP and age, gender, region, and these ocular biometric parameters. Results: The mean IOP were 15.90 ± 0.07 mmHg in urban areas, 15.92 ± 0.06 mmHg in county towns, and 16.66 ± 0.08 mmHg in rural areas, with statistically significant differences among regions (p < 0.05). No statistically significant differences were observed in mean IOP between boys (16.06 ± 3.15 mmHg) and girls (16.08 ± 3.09 mmHg), or between the right eye (16.07 ± 3.12 mmHg) and left eye (16.11 ± 3.04 mmHg). Mean IOP at ages 4, 5, and 6 years were 15.96 ± 3.15 mmHg, 16.13 ± 3.06 mmHg, and 16.12 ± 3.15 mmHg, respectively, with no significant differences across age groups (p > 0.05). IOP exhibited a statistically significant negative correlation with corneal curvature and cylinder(CYL) power (r = -0.23, p < 0.05; r = -0.18, p < 0.05), while it showed a statistically significant positive correlation with axial length (r = 0.27, p < 0.05). Although IOP was positively correlated with spherical lens power and equivalent spherical power, these correlations were not statistically significant (r = 0.12, p > 0.05; r = 0.10, p > 0.05). Multiple regression analysis indicated that corneal curvature did not have a significant independent effect on IOP, whereas cylinder power and axial length had significant effects (β = -0.21, p < 0.05; β = 0.25, p < 0.05). Conclusion: There are regional variations in IOP among preschool children, with the highest IOP in rural areas, followed by county towns, and the lowest in urban areas. Axial length demonstrated a nonlinear positive correlation with IOP, while cylinder power showed a negative correlation, although individual variability was substantial.