• Posted August 26, 2024

An Alzheimer's Drug May Also Slow Lewy Body Dementia

A type of drug used to treat Alzheimer’s disease appears to slow the progression of Lewy body dementia, the brain disease that afflicted comedian Robin Williams prior to his suicide.

Cholinesterase inhibitors prevent the breakdown of acetylcholine, a chemical messenger important for memory and learning.

The drugs are commonly prescribed to treat symptoms related to memory, thinking, language, judgment and other thought processes in Alzheimer’s patients, according to the Alzheimer’s Association.

Now, new research suggests the drugs might also help people with Lewy body dementia, according to new data from nearly 1,100 people with the degenerative brain disease.

The medications, known as ChEIs, significantly slowed cognitive decline in Lewy body dementia patients compared to another Alzheimer’s drug called memantine, researchers reported Aug. 23 in the journal Alzheimer’s & Dementia.

“Our results highlight the potential benefits of ChEIs for patients with [Lewy body dementia] and support updating treatment guidelines,” said senior researcher Maria Eriksdotter, a professor of neurobiology with the Karolinska Institutet in Sweden.

Lewy body dementia is caused by abnormal deposits of a protein called alpha-synuclein in the brain’s nerve cells.

These deposits, called Lewy bodies, cause a swift decline in brain function compared to Alzheimer’s and other forms of dementia, researchers noted. Patients experience problems with thinking and memory, have visual hallucinations, and suffer movement symptoms similar to Parkinson’s disease.

Lewy body dementia accounts for 10% to 15% of dementia cases, researchers said in background notes. As many as 14 million people worldwide are projected to suffer from this form of dementia by 2050.

An autopsy following his death in August 2014 revealed that Robin Williams’ brain was riddled with Lewy bodies.

“He died from suicide in 2014 at the end of an intense, confusing, and relatively swift persecution at the hand of this disease's symptoms and pathology,” his widow, Susan Schneider Williams, wrote in the journal Neurology in 2016.

Williams suffered from tremors, paranoia, delusions, insomnia and memory problems in the months prior to his death, his widow wrote in a special editorial.

“All four of the doctors I met with afterwards and who had reviewed his records indicated his was one of the worst pathologies they had seen,” Williams wrote. “He had about 40% loss of dopamine neurons and almost no neurons were free of Lewy bodies throughout the entire brain and brainstem.”

For the new study, researchers combed a Swedish registry of cognitive disorders for patients with Lewy body dementia. They found 814 patients who had been treated with ChEIs, and compared them against 133 patients who’d received memantine and another 148 who’d taken neither drug.

“There are currently no approved treatments for [Lewy body dementia], so doctors often use drugs for Alzheimer’s disease, such as cholinesterase inhibitors and memantine, for symptom relief,” said lead researcher Hong Xu, an assistant professor of neurobiology at Karolinska Institutet.

Cognitive tests taken by all the patients showed that those on ChEIs had a slower decline in their brain function during a five-year follow-up period compared with the two other groups.

In particular, the ChEIs galantamine (Razadyne) and donepezil (Aricept) appeared to help arrest the progression of symptoms related to Lewy body dementia, researchers found.

ChEIs also were associated with a 34% lower risk of death within the first year of Lewy body dementia diagnosis, researchers found.

These results should form the basis of new clinical trials to test cholinesterase inhibitors as a treatment for Lewy body dementia, researchers concluded.

More information

The National Institute on Aging has more about Lewy body dementia.

SOURCE: Karolinska Institutet, news release, Aug. 21, 2024