Evaluation of the association of macular ganglion cell–inner plexiform layer thickness and myopia in Chinese young adults

Purpose To describe the distribution of ganglion cell–inner plexiform layer (GCIPL) thickness among Chinese young adults and report whether the decreased GCIPL thickness is associated with myopia. Methods In this study, we included Chinese young adults who underwent Cirrus spectral domain-optical coherence tomography (SD-OCT). SD-OCT was used to measure average and minimum GCIPL thickness, and GCIPL thickness at all sectors. Subfoveal choroidal thickness (CT), axial length (AL), and spherical equivalents (SE) were also measured. Results A total of 348 eyes were included in the analysis. Average GCIPL thickness showed a significant difference between myopes and emmetropes, with 87.89 ± 3.65 μm for emmetropic groups and 82.65 ± 4.96 μm for myopic groups. The GCIPL thickness was significantly thinner in myopia than in emmetropia at all locations ( P < 0.05), affirming that myopia was associated with thinner GCIPL thickness ( P = 0.001). The mean subfoveal CT also showed a significant difference between myopes and emmetropes, with 330.57 ± 9.43 μm for emmetropic groups and 265.98 ± 4.12 μm for myopic groups. GCIPL (OR 0.863, 95% CI, 0.785–0.949), AL (OR 2.499, 95% CI, 1.532–4.075) and intraocular pressure (IOP) (OR 1.250, 95% CI, 1.086–1.438) revealed significant associations with myopia. When adjusting for AL, IOP, and anterior chamber depth (ACD) in the myopia subgroup, the GCIPL thickness remained positively associated. Conclusions In a specific Chinese young population, myopic eyes have measurably less macular GCIPL thickness than normal eyes. Decreasing GCIPL thickness may be associated with the progression of myopia.