Optical coherence tomography findings in children of patients with Alzheimer-type dementia

Background Ocular imaging receives much attention as a source of potential biomarkers for dementia. This study aims to study structural changes in the retina and optic nerve in children of healthy and demented parents and to confirm the applicability of optic nerve tomography as a potential noninvasive marker for the early diagnosis of dementia. Methods Healthy individuals with a parent diagnosed with Alzheimer's disease (AD) and healthy controls with healthy parents were included in the study. Included individuals had undergone Montreal Cognitive Assessment Scale and Mini-Mental Test by a single neurologist physician to confirm not having dementia. All the subjects then underwent a complete ophthalmological examination, including refractive error and keratometry readings, best-corrected visual acuity measurement with a Snellen chart (converted to LogMAR), intraocular pressure (IOP) measurement, slit-lamp biomicroscopy, dilated fundus examination, axial length measurement and optical coherence tomography (OCT) for the parapapillary retinal nerve fiber layer (pRNFL), basal membrane opening-minimum rim width (BMO-MRW), and macular thickness analysis. Only the right eyes of the subjects were evaluated. OCT findings of these two groups were compared. Results The temporosuperior sector the pRNFL thicknesses at all 3 circles (3.5, 4.1, and 4.5) were significantly thinner in the children of the dementia group than in healthy controls (p = 0.023, 0.039, and 0.016, respectively). For the remaining sectors, the thicknesses of the pRNFL were also thinner, however, the differences were not significant (p > 0.05 for all). BMO-MRW at all sectors, were not also different significantly between the groups (p > 0.05 for all). Parents' dementia grade were found to be an important factor that the BMO-MRW at the temporal sector, got thinner with increasing grade (B = - 20.631, 95% CI - 42.121 to - 0.019, and p = 0.049). Conclusion We believe that OCT can be used as a noninvasive biomarker in the preclinical period, when supported by more extensive studies in people whose parents have AD.