Cognitive Decline Associated With Middle-Age Sleep Problems

Richard S. Isaacson, MD


April 06, 2018

I'm Dr Richard Isaacson, here for Medscape. I'm director of the Alzheimer's Prevention Clinic at Weill Cornell Medicine at NewYork-Presbyterian.

A new study looks at, for the first time, midlife sleep changes and how that affects cognitive function and Alzheimer's risk over time.[1] This was a large meta-analysis that pooled several studies, and it showed some really interesting things.

For a while now, we've known that sleep disturbances and Alzheimer's disease go hand-in-hand. There's been some really exciting research done on when a person isn't sleeping well—maybe that's like pressing the fast-forward button to amyloid in the brain.

This study is new and unique because it looks at midlife sleep complaints. For example, insomnia during midlife actually shows a higher risk for cognitive decline just a decade or so later. Nightmares in midlife also predict cognitive decline 20-30 years later. When a practicing clinical physician is trying to evaluate a person for Alzheimer's disease risk, doing a history on sleep is super important.

How do we intervene on sleep? Do we really know that this is a chicken or an egg thing? Is the sleep trouble really causing Alzheimer's disease or contributing to it, or is the sleep trouble really one of the earliest manifestations of what Alzheimer's disease is in the future? We need a lot more studies to figure this out, and we need long-term studies to analyze sleep patterns and brain biomarker imaging from amyloid to tau. I do think that the area is something that's important and something that deserves a lot more study.

How we do this from a practical clinical perspective? When a person in midlife is coming in with sleep disturbances, I think one of the key points is trying to figure out exactly what that disturbance is and also focusing on sleep hygiene. More and more nowadays, people are glued to their phones; you have the artificial light, people are texting and talking, and there's really not an ideal wind-down period before bed.

One of the key things that I help my patients with is setting time and getting prepared for sleep. No TV in the bedroom, shutting off electronic devices 30 minutes before bed, avoiding stimulating activities at night, and getting in a mode or a mindset that we have to prepare for sleep—whether it's setting an alarm on your phone, having your partner or spouse help you get in that mindset, it's very important for proper sleep hygiene.

Avoid certain sleep agents—for example, diphenhydramine or other benzodiazepines. These medicines may take the edge off and get you to sleep, but may not provide restful sleep. Recent studies suggest that overuse of some of these medications may be associated with an increased risk for dementia and Alzheimer's disease down the line.

The other aspect is, what about caffeine in coffee? Caffeine during the day, early in the day, may not be a problem, but after 1 or 2 PM, that may interrupt sleep and wake cycles. Thinking about sleep hygiene is key.

When it comes to using medication management for sleep, we should always try to minimize when possible and maybe start with something that has less of a potential for a downside. For example, in my clinical practice, occasionally if someone has trouble falling asleep, I may recommend a low dose of the supplement melatonin. Although there is no perfect evidence and you may only get to sleep maybe 10 minutes sooner, it's better than nothing and it's probably safe over the long haul for the brain.

However, there are other agents out there, and we always suggest that when someone's having insomnia or other sleep disturbances, consider seeing a sleep specialist or having a sleep study.

For Medscape, it's Dr Richard Isaacson.


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