Correlations of retinal morphology with clinical symptoms, blood-brain barrier, and brain structure in patients with Alzheimer's disease

BackgroundPatients with Alzheimer's disease (AD) displayed abnormal retinal morphology; however, its potential associations with clinical symptoms, damage of the blood-brain barrier (BBB), and brain structure are unclear.ObjectiveTo investigate the correlations of retinal morphology with clinical symptoms, BBB damage, and brain structure in AD patients.MethodsIn 97 patients with mild cognitive impairment due to AD (AD-MCI) and dementia due to AD (AD-D), retinal morphology, clinical symptoms, BBB variables in cerebrospinal fluid, and brain structure variables, including medial temporal atrophy (MTA), global cortical atrophy (GCA), and white matter hyperintensities scores were evaluated.ResultsIn AD patients, peripapillary superotemporal retinal nerve fiber layer thickness (NFLT) was positively correlated with memory score; the NFLTs of average, inferior, and inferotemporal quadrants were negatively correlated with the level of matrix metalloproteinase 3 level in cerebrospinal fluid; the NFLTs of average, superior, and inferior quadrants were negatively correlated with MTA and GCA scores; superotemporal NFLT was negatively correlated with GCA score. In AD-MCI group, superotemporal NFLT maintained a positive correlation with memory score; the NFLTs in superior and nasoupper quadrants were negatively associated with GCA score. In AD-D group, superonasal NFLT was negatively correlated with matrix metalloproteinase 9 level in cerebrospinal fluid.ConclusionsIn AD patients, thinner peripapillary NFLT mirrors worse memory, significant BBB damage, the atrophy of medial temporal lobe and cortex. In AD-MCI patients, thinner NFLT mirrors worse memory and cortical atrophy. In AD-D patients, thinner NFLT mirrors significant BBB damage.