Abstract
Purpose:
To investigate a possible association between myopia and glaucoma risk in a young healthy adult population.
Methods:
We performed a cross-sectional survey of 115 young healthy graduate student volunteers from the University of California San Francisco. Individuals who had previously undergone LASIK were excluded. Subjects underwent a comprehensive ophthalmic examination including visual acuity, refraction, slit lamp exam, ophthalmoscopy, intraocular pressure measurement, A-scan biometry, automated perimetry, and optic nerve and anterior segment optical coherence tomography. The predictor variable was refractive status and subjects were categorized into two groups: Group A - emmetropia or mild myopia (0.99 to -2.99 D) and Group B - moderate to severe myopia (>-3.00 D). Outcome variables included intraocular pressure, retinal nerve fiber layer thickness, visual field mean deviation and pattern deviation. In addition to a comparative analysis of the mean value of each outcome variable between the two groups, a multivariate linear regression model was created to examine the independent association between spherical equivalent and each outcome variable adjusting for potential confounders including age, gender, and ethnicity.
Results:
Mean age was 24.63 years and 61.74% of subjects were female. 56 subjects with emmetropia or mild myopia (48.7%) were in Group A and 59 subjects with moderate to severe myopia (51.3%) were in Group B. In comparing Group A versus Group B, the mean intraocular pressure was significantly lower (13.13 vs 14.68 mmHg, p-value .0064), the mean retinal nerve fiber layer was significantly thicker (110.00 vs 104.24 μm, p-value .0016), and the mean visual field mean deviation and pattern deviation were significantly more suspicious for abnormality (-0.34 vs -1.29 dB, p-value <.0001 and 1.46 vs 1.71 dB, p-value 0.02). After adjusting for age, gender, and ethnicity using a multivariate linear regression, the regression coefficients for the relationship between spherical equivalent and each of the outcome variables remained statistically significant.
Conclusions:
The association between greater myopia and higher IOP, thinner retinal nerve fiber layer thickness, and more suspicious visual field mean deviation and pattern deviation may represent greater glaucoma risk among young myopes, consistent with findings of increased glaucoma risk in older myopic populations from previous studies.
Keywords: 605 myopia •
758 visual fields •
568 intraocular pressure