No difference in retinal fluorescence after oral curcumin intake in amyloid‐proven AD cases compared to controls

INTRODUCTION: Previous work has showed the in vivo presence of retinal amyloid in Alzheimer's disease (AD) patients using curcumin. We aimed to replicate these findings in an amyloid biomarker–confirmed cohort. METHODS: Twenty‐six patients with AD (age 66 [+9], Mini‐Mental Status Examination [MMSE] ≥17) and 14 controls (age 71 [+12]) used one of three curcumin formulations: Longvida, Theracurmin, and Novasol. Plasma levels were determined and pre‐ and post‐curcumin retinal fluorescence scans were assessed visually in all cases and quantitatively assessed in a subset. RESULTS: Visual assessment showed no difference between AD patients and controls for pre‐ and post‐curcumin images. This was confirmed by quantitative analyses on a subset. Mean conjugated plasma curcumin levels were 198.7 nM (Longvida), 576.6 nM (Theracurmin), and 1605.8 nM (Novasol). DISCUSSION: We found no difference in retinal fluorescence between amyloid‐confirmed AD cases and control participants, using Longvida and two additional curcumin formulations. Additional replication studies in amyloid‐confirmed cohorts are needed to assess the diagnostic value of retinal fluorescence as an AD biomarker.