Purpose: To investigate the association between myopia and ganglion cell layer and inner plexiform layer (GCIPL) in diabetic patients without clinically diabetic retinopathy (DR). Methods: Guangzhou Diabetic Eye study was a longitudinal study. A total of 1165 adults aged 30-80 years were recruited in this study which divided into 3 groups according to the presence of myopia (spherical equivalence, SE≤-3 diopters) and diabetics: healthy group (n=508); diabetes mellitus group (n=525); diabetes mellitus (DM)+myopia group(n=132). GCIPL was measured via swept-source optical coherence tomography. Univariable model and multivariable model were used to showing the association of GCIPL change and baseline parameters. Results: SE was 1.07±1.06D in healthy group, 1.02±1.00D in diabetes mellitus group and -5.36±2.30 D in DM + myopia group(P<0.001). The baseline GCIPL thickness were 71.1±0.3μm, 74.4±0.2 μm, 71.7±0.5μm, respectively. The slope of GCIPL thickness was -0.10 (95%CI: 0.05, -2.03) μm/year in healthy group, which was 12 folds faster than those in diabetes group (-1.21 [95%CI: 0.05, -24.04], P<0.001) μm/year and 22 folds higher among those in DM + myopia group (-2.17 [95%CI: 0.10, -21.63], P=0.009) μm/year. Conclusions: Both myopia and diabetes status accelerate macular ganglion cell layer and inner plexiform layer thinning in diabetic patients without diabetic retinopathy.
