Lewy body disease, which includes dementia with Lewy bodies (DLB) and Parkinson’s disease with and without dementia, is the second most common neurodegenerative disorder, following Alzheimer’s disease. DLB accounts for approximately 10-15 per cent of dementia cases and is characterised by changes in sleep, behaviour, cognition, movement, and regulation of automatic bodily functions.

“There are currently no approved treatments for DLB, so doctors often use drugs for Alzheimer’s disease, such as cholinesterase inhibitors and memantine, for symptom relief,” says Hong Xu, assistant professor at the Department of Neurobiology, Care Sciences and Society, Karolinska Institutet and first author of the paper. “However, the effectiveness of these treatments remains uncertain due to inconsistent trial results and limited long-term data.”

In the current study, researchers have examined the long-term effects of cholinesterase inhibitors (ChEIs) and memantine compared with no treatment for up to ten years in 1,095 patients with DLB. They found that ChEIs may slow down cognitive decline over five years compared to memantine or no treatment. ChEIs were also associated with a reduced risk of death in the first year after diagnosis.

“Our results highlight the potential benefits of ChEIs for patients with DLB and support updating treatment guidelines,” says Maria Eriksdotter, professor at the Department of Neurobiology, Care Sciences and Society, Karolinska Institutet and last author of the paper.

Due to the study’s observational nature, no conclusions can be drawn about causality. The researchers did not have data on patient lifestyle habits, frailty, blood pressure, and Alzheimer’s disease co-pathology, which may have influenced the findings. Another limitation of the study is that it remains challenging to diagnose DLB accurately.

The research was mainly financed by StratNeuro, the Center for Innovative Medicine (CIMED), the KI foundations and the Swedish Research Council.