Before getting dementia caused by Alzheimer’s disease people go through a pre-dementia or prodromal phase. It is not clear whether this also happens in people with dementia with Lewy bodies (DLB).

Identifying prodromal symptoms should aid early identification of treatment responders (drug and non-drug) to prevent subsequent decline and/or delay dementia onset, to plan for the future, and avoid drugs that might cause serious side effects.

What did we do, who was involved and what was the output?

We have identified three forms of prodromal DLB: mild cognitive impairment (MCI-DLB) where there are subtle problems with thinking abilities but no dementia; delirium-onset-DLB where people experience unexplained episodes of confusion; and psychiatric-onset DLB where various psychiatric symptoms, such as depression or psychosis, occur prior to onset of DLB. From observations in our own research studies, speaking with patient/carers in workshops, and reviewing the medical literature we have led (McKeith, Taylor, Donaghy, and Thomas) on the publication of international research criteria in 2020 for the diagnosis of prodromal DLB[1].

What are the next steps?

We now want to test whether these criteria are useful in the clinical setting and to encourage their use and uptake in the rapidly growing DLB international collaborative research network. The Newcastle BRC-supported LewyPro and SUPERB research projects are world-leading studies tracking the progression of people from prodromal Lewy body disease into dementia and sometimes to death and autopsy. Findings from these studies helped inform our new research criteria for prodromal DLB and we have subsequently found strong evidence for the diagnostic accuracy of imaging tests that are already available in the NHS[2,3] and which could be used for early DLB diagnosis. As we gather more data, we are evaluating how well other imaging and blood-based tests are in detecting early stage or prodromal DLB.

We are currently leading an international expert group (Thomas, Donaghy), supported by patient/carer groups, to review the use of these tests; this will feed into our 2022 International LBD Conference, which we are hosting, where a major focus will be on determining whether the data are robust enough to extend the use of our prodromal DLB diagnostic recommendations into routine clinical use.

References

1. McKeith IG et al. Neurology. 2020 Apr 28;94(17):743-755
2. Roberts G et al. Br J Psychiatry. 2020 Dec 23:1-7.
3. Roberts G et al. Neurology 2021 Jun 96 (23) e2801-e2811