A common sleeping pill can slash the levels of Alzheimer’s linked proteins in the brain, a small study suggests.
Researchers at Washington University in St Louis, Missouri, tracked 38 people who used suvorexant — a prescription medication sold under the brand name Belsomra — for two nights.
Those who took the highest dose had amyloid levels that were up to a fifth lower than other participants in their spinal fluid by the next morning.
Scientists are not urging people to start taking the pills every night, saying much more extensive research is needed to back up the results.
Previous papers have suggested that taking sleeping pills can actually raise someone’s risk of the disease because they disrupt a healthy night’s sleep.
Researchers at the University of Washington in St Louis, Missouri, said that people who took higher doses of suvorexant — sold under the brand name Belsomra — had lower levels of amyloid and tau proteins in their spinal fluid. They added it was premature to start taking the pills constantly and that more work was needed
Patients were administered a high dose of suvorexant (Belsomra) over two nights (shown)
About six million Americans living with Alzheimer’s in the US, with this number expected to nearly triple to 14million by 2060.
Scientists are not clear on the cause, but some suggest that a build-up of proteins in the brain — such as amyloid and tau — can slow communication between cells and even kill them leading to the disease.
Other theories point to factors such as damage to blood vessels running through the brain as factors behind the disease.
Sleep helps to clear these proteins from the brain, studies show.
Besides pills, people can also try keeping a consistent bedtime, not staring at screens before bed and avoiding bright lights in late hours to help with sleep.
Suvorexant is only available on prescription in the US for those with insomnia, priced at about $15 per pill — although on insurance it is available at a lower price.
More than $500million is made from suvorexant every year, according to data from its owner and New Jersey-based pharmaceutical company Merck.
Senior author Dr Brendan Lucey, a sleep medic, said that the study was ‘small’ and a ‘proof-of-concept’.
‘It would be premature for people who are worried about developing Alzheimer’s to interpret it as a reason to start taking suvorexant every night,’ he said.
‘We don’t yet know whether long-term use is effective in staving off cognitive decline, and if it is, at what dose and for whom.’
He added: ‘Still, these results are very encouraging.
‘This drug is already available and proven safe, and now we have evidence it affects the levels of proteins that are critical for driving Alzheimer’s disease.’
Suvorexant works by blocking receptors in the brain for the hormone orexin, which promotes wakefulness.
Scientists suggest that this can help someone get to sleep faster. It is not clear how they may impact sleep quality.
There are three orexin inhibitors — including suvorexant — that are currently approved by the Food and Drug Administration (FDA) for use in the US.
In the first study of its kind, scientists recruited 38 participants aged 45 to 65 with no cognitive impairments.
They were split into three equal groups and given either a high dose of the drug (20mg), a low dose (10mg) or a placebo.
Each was administered the pill at 9pm and then allowed to fall asleep at a specialist lab in St Louis.
Their spinal fluid was sampled every two hours for 36 hours to check levels of amyloid and tau proteins.
Sampling began one hour before the sleeping aid was administered.
Scientists found that after the first night, patients who received the highest dose of suvorexant had a 10 to 20 percent dip in amyloid levels.
They also found that levels of tau fell by 10 to 15 percent.
There was not a significant difference between peers who received a low dose and the rest who got the placebo.
By 24 hours, tau levels in the high-dose group had risen but amyloid levels remained low compared to the placebo group.
A second dose was then administered for night two, which again led to lower levels of the proteins in the high-dose group.
Dr Lucey said: ‘If we can lower amyloid every day, we think the accumulation of amyloid plaques in the brain will decrease over time.
‘And hyperphosphorylated tau is very important in the development of Alzheimer’s disease, because it’s associated with forming tau tangles that kill neurons.
‘If you can reduce tau phosphorylation, potentially there would be less tangle formation and less neuronal death.’
Dr Lucey, who was part of the team that first suggested the proteins could be behind Alzheimer’s, will now conduct longer-term studies to assess the effects of orexin inhibitors in people at higher risk of dementia.
Dr Lucey added: ‘Future studies need to have people taking these drugs for months, at least, and measuring the effect on amyloid and tau over time.
‘We are also going to be studying participants who are older and may still be cognitively healthy, but who already have some amyloid plaques in their brains.
‘This study involved healthy middle-aged participants. The results may be different in an older population.
‘I am hopeful that we will eventually develop drugs that take advantage of the link between sleep and Alzheimer’s to prevent cognitive decline.
‘We are not quite there yet. At this point, the best advice I can give is to get a good night’s sleep if you can, and if you can’t, to see a sleep specialist and get your sleep problems treated.’
The study was published in the journal Annals of Neurology.
