Sleeping Pills Linked to Lower Levels of Alzheimer's Disease Proteins

A recent study published in the Annals of Neurology identified a link between sleeping pill use and lowered levels of Alzheimer's disease protein. Protein buildups and plaques identified in autopsies of patients with Alzheimer’s disease are thought to be the primary cause of the illness and its progression.

In this clinical trial, the researchers recruited 38 patients between 45 and 65. Each patient — without cognitive impairments — was assigned to one of three groups: placebo, 10 mg suvorexant, or 20 mg suvorexant.

According to the Mayo Clinic, oral suvorexant is a standard treatment for insomnia as it is a central nervous system depressant. Under the direction of a licensed medical practitioner, patients can take this medication roughly 30 minutes before bed for faster and more stable sleep.

In this trial, patients were given the drug at 9:00 PM. Starting at 8:00 PM, a 6 mL sample of cerebrospinal fluid was taken from each patient every two hours through a lumbar catheter. Samples were collected for 36 hours and tested for amyloid-β, tau, and phospho-tau using immunoprecipitation and liquid gas chromatography–mass spectrometry (GC–MS).

When analyzing the data, the researchers focused on the ratio of phosphorylated-tau-threonine-181 to unphosphorylated-tau-threonine-181. Participants assigned to the 20 mg suvorexant had significantly lower ratios than those in the placebo group, with 10–15% reductions.

Researchers also calculated the ratio of phosphorylation at tau-serine-202 and tau-threonine-217, noting that there was no significant decrease with suvorexant use. Finally, they analyzed the levels of amyloid-β proteins, finding that within five hours of drug administration, suvorexant decreased levels by 10–20%.

Despite the potential utility of suvorexant in Alzheimer’s treatment, the drug has a wide range of side effects. Potential risks range from unusual sleepiness to loss of memory, lack of appetite, behavioral changes, suicidal thoughts, and hallucinations. Additionally, there are multiple contraindications for the drug depending on the patient’s medical history and medication regimen,

While additional research is necessary to understand suvorexant, its impacts on neurodegenerative diseases, and its safety profile, this study may point to a new research route for Alzheimer's disease treatment.