Abstract
Purpose :
Autism spectrum disorder (ASD) is a heterogeneous neurodevelopmental disorder affecting the developing brain structures. Since retina is an extension of the central nervous system, we compared the thickness of retinal layers among patients with ASD with healthy individuals. We also investigated the association between the retinal structures and cognitive function in these patients.
Methods :
In this retrospective study, we analyzed retinal optical coherence tomography (OCT) measurements of 201 individuals enrolled in the UK Biobank. We excluded individuals with retina or optic nerve pathologies, as well as individuals with a known history of neurological disorders. Thickness measurements of 7 distinct retinal layers were included in the analysis: retinal nerve fiber layer (RNFL), ganglionic cell/inner plexiform layer (GC/IPL), inner nuclear layer (INL), outer plexiform layer and outer nuclear layer (OPL/ONL), inner segment of photoreceptors (IS), outer segment of photoreceptors (OS), and retinal pigment epithelium (RPE). A general linear model was used to analyze the variation of the retinal layer thicknesses in the case and control groups while adjusting for age, sex, ethnic origin, smoking status, and refractive errors. The association between cognitive function and retinal layers of ASD patients was evaluated using Pearson correlation analysis.
Results :
We included 67 (32.8% female) patients with ASD and 134 age- and sex-matched healthy controls. The mean age of patients was 50.5 ± 7.5, which was comparable to the control group (51.1 ± 7.34, p=0.6). After adjusting for demographic factors, smoking status, and refractive error, we found that the thickness of RNFL was significantly higher among ASD patients compared to the control group (adjusted mean difference (aMD), 3.18 µm, p<.001). In contrast, patients with ASD had significantly thinner RPE (aMD, -1.03 µm, p=0.03) and OPL/ONL (aMD, -2.21 µm, p=0.01). We found no correlation between cognitive function, as evaluated by Fluid Intelligence/Reasoning and Reaction Time Test, and the thickness of selected retinal layers in ASD group (p>0.05).
Conclusions :
We confirmed the substantial alteration of retinal structure in ASD patients, which did not correlate with the degree of cognitive impairment. Our study provides new insight into potential new biomarkers for diagnosis of ASD.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.