Peripapillary retinal nerve fiber layer thickness measured using optical coherence tomography as a marker of Alzheimer's disease

Abstract Background Optical coherence tomography (OCT), is an advanced, noninvasive technology that can provide the images of retinal structure, including peripapillary retinal nerve fiber layer (pRNFL), macular retinal thickness (MRT), as well as macular volume (MV). However, whether the retinal structure varied in Alzheimer's disease (AD) patients was still unclear. This study aims to detect the retinal changes of AD patients and explore their correction with severity of disease and classic biomarker. Method 78 AD patients and 188 HC matched with age and sex were enrolled in this study. The pRNFL thickness, MRT and MV were assessed using OCT. In addition, Aβ42, Aβ40 and tau protein in plasma were detected using Simoa technology. Result The results showed that the pRNFL thickness of AD patients was significantly thinner than HC (96.76±10.44 vs 101.4±17.74, p=0.023). Compared with HC, MRT and MV were reduced in AD patients, but the differences were not significant(p>0.05). Furthermore, the pRNFL thickness was significantly negatively correlated with MMSE (r=‐0.362, p=0.005) and disease duration (r=‐0.295, p=0.002); In addition, the pRNFL thickness was positively correlated with t‐tau protein in plasma(r=0.409, p=0.002); while negatively correlated with Aβ42/40 in plasma(r=‐0.277, p=0.041). However, there was no significant correction between neither MRT nor MV and MMSE, disease duration, Aβ42, Aβ40 and tau protein in plasma (p>0.05). Conclusion These results supported that pRNFL thickness measured using OCT may serve as a useful predictor of AD.