Background: 123I-FP-CIT imaging is a diagnostic tool to help differentiate dementia with Lewy Bodies (DLB) from Alzheimer’s disease (AD). However, in animals, cholinesterase inhibitors (ChEi) have been reported to reduce radioligand binding to the striatal dopamine transporter. Since ChEi are frequently used in people with dementia it is important to determine whether their use affects 123I-FP-CIT uptake in the striatum.
Objective: To clarify whether chronic cholinesterase inhibitor therapy modulates striatal DAT binding measured by 123I-FP-CIT in patients with AD, DLB and Parkinson’s disease with dementia (PDD).
Design: Cross-sectional study in 99 patients with AD (9 on ChEi, 25 not on ChEi), DLB (9 on ChEi, 19 not on ChEi) and PDD (6 on ChEi, 31 not on ChEi) comparing 123I- FP-CIT striatal binding (caudate, anterior and posterior putamen) in patients on with those not on ChEi, correcting for key clinical variables including diagnosis, age, sex, MMSE score, severity of parkinsonism and concurrent antidepressant use.
Results: As previously described 123I-FP-CIT striatal uptake was lower in DLB and PDD subjects compared to those with AD. Median duration of ChEi use was 180 days. 123I-FP-CIT uptake was not significantly reduced in subjects on ChEi compared those without (mean percentage reduction: AD, 4.3%; DLB, 0.7%; PDD, 6.1%, p = 0.40). ChEi use did not differentially affect striatal 123FP-CIT uptake between patient groups (p = 0.83).
Conclusions: Use of ChEi does not significantly influence the ability of 123I-FP-CIT imaging to distinguish AD from DLB.
- cholinesterase inhibitor
- dopamine transporter