Retinal Microvascular Features Assessed by Optical Coherence Tomography Angiography in Attention Deficit Hyperactivity Disorder

Abstract

Background: Attention deficit hyperactivity disorder (ADHD) lacks objective biomarkers that may complement clinical diagnosis. Optical coherence tomography angiography (OCTA) enables non-invasive quantitative assessment of retinal microvasculature and has emerged as a potential tool to explore neurovascular features associated with neurodevelopmental disorders. The aim of this study was to comparatively evaluate macular and peripapillary OCTA parameters in individuals with ADHD and neurotypical controls. Methods: This comparative case-control study involved 200 eyes (100 from 50 patients with ADHD and 100 from 50 neurotypical controls) belonging to the same well-characterized cohort previously evaluated using structural optical coherence tomography (OCT). Macular and peripapillary OCTA scans were obtained, and quantitative parameters related to vessel density, perfusion density, and peripapillary flow metrics of the superficial retinal capillary plexus were analyzed separately for right and left eyes. Group comparisons were performed using independent-samples t-tests and analysis of covariance adjusted for age, sex, and axial length, with correction for multiple comparisons. Results: After adjustment for age, sex, and axial length, no OCTA parameter showed statistically significant between-group differences after correction for multiple comparisons. Across parameters, mean differences were small and did not provide statistical evidence of an effect under the prespecified analytical framework. Conclusions: Superficial OCTA-derived microvascular parameters did not demonstrate robust between-group differences in ADHD in this cohort. These results suggest that when restricted to the superficial capillary plexus, OCTA metrics are unlikely to serve as standalone biomarkers for ADHD.