Affiliations: [a] Department of Ophthalmology, School of Medicine, Nihon University, Chiyoda-ku, Tokyo, Japan
| [b] Department of Neuropsychiatry, Nippon Medical School, Bunkyo-ku, Tokyo, Japan
Correspondence:
[*]
Correspondence to: Prof. Hiroyuki Shimada, MD, PhD, Department of Ophthalmology, Nihon University Hospital, 1-6 Surugadai, Kanda, Chiyodaku, Tokyo 101-8309, Japan. Tel.: +81 3 3293 1711/Ext. 3526; Fax: +81 3 3293 1734; E-mail: sshimada@olive.ocn.ne.jp.
Abstract: Background:Histopathological studies have confirmed that soft drusen contains amyloid-β (Aβ). Objective:To examine the relationship between the area of soft drusen in the macular area and cerebral Aβ accumulation or plasma Aβ level in elderly persons without dementia. Methods:Fourteen consecutive patients (18 eyes) aged ≥50 years with macular soft drusen were studied prospectively. From color fundus photographs, the area of soft drusen (pixel) within a 6,000 μm diameter with the macula as center was measured. Standard uptake value ratio (SUVR) was obtained from positron emission tomography using florbetapir, which indicates the ratio of cerebral cortical-to-cerebellar Aβ accumulation. Ratio of plasma Aβ1-42 to Aβ1-40 level was calculated. Results:Mean age was 73.3±7.6 years. The soft drusen area was 4.32±2.42 mm2. The SUVR was 1.08±0.15. Plasma Aβ1-42/Aβ1-40 ratio was 0.17±0.08. When SUVR ≥1.10 was defined as positive and <1.10 as negative, the soft drusen area in SUVR-positive patients (6.19±1.14 mm2) was significantly (p = 0.0043) larger than that in SUVR-negative patients (3.13±2.27 mm2). Multivariate regression analysis showed that SUVR positivity correlated with soft drusen area (p = 0.0484) and with Voxel-based Specific Regional Analysis System for Alzheimer’s Disease score (p = 0.0360). However, there was no correlation with gender (p = 0.1921), age (p = 0.2361), Alzheimer’s Disease Assessment Scale score (p = 0.6310), Mini-Mental State Examination score (p = 0.4246), or plasma Aβ1-42/Aβ1-40 ratio (p = 0.8398). Conclusion:Among elderly persons without dementia, the area of soft drusen was larger in those with more extensive cerebral Aβ accumulation. The area of soft drusen may be a biomarker of cerebral Aβ accumulation.
