bad sleep in senior citizens could be an early symptom of alzheimer’s
Sleep seems to be one of the things we most readily disregard. We say that sleep is for the week or that we’ll sleep when we’re dead while reaching for that third cup of coffee. And with our busy lives in which we struggle to pack enough time to do everything we need to do and actually enjoy our existence, sleep seems like the easiest thing to give up. Besides, according to studies, if we sleep too much, we’re putting ourselves at risk of various health problems. So finish that energy drink, slap yourself awake, and carpe the crap out of that diem, right? Well, not so fast, especially if you’re older and noticed that you’re having a lot of trouble getting a good night’s sleep, even if you really try.
As it turns out, bad, fitful sleep might be a precursor to Alzheimer’s disease, the incurable buildup of toxic plaque deposits that quite literally eat away at your brain. Now, this doesn’t mean you’ll develop the disease if you sleep too little or poorly, there’s a host of other issues to content with if you don’t average about six to seven hours of sleep per night. But according to new research, a lack of sleep necessary to consolidate memories is correlated with an excess of tau proteins, one of the signs of Alzheimer’s, and indicating that beta amyloid plaques have been building up in the patient’s brain as tangles of tau proteins interfere with neurons.
why and how is memory affected by alzheimer’s?
Loss of memory is typically the first reported symptom of the disease because it’s the most noticeable while other areas of the brain may be under attack. As Alzheimer’s progresses, related neural structures start failing, leading to difficulties in language, social interactions, and basic self-care. How quickly this happens depends on the speed of the tau protein spread, the beta amyloid buildup, and the failure of glial cells to clean up the toxic proteins now polluting the patient’s mind. One of the manifestations of this process is an atrocious quality of sleep as the disease progresses and its mechanisms interfere with functions required for a good, restful night in bed.
Since one of those required functions is letting the brain consolidate memories, researchers from Washington University School of Medicine in St. Louis studied the sleep patterns of 119 people age 60 or older recruited from an Alzheimer’s research institute. Looking specifically for slow wave sleep, the kind which reflects the brain trying to prune and clean up itself, they found that levels of toxic tau protein buildup increased as memory-consolidating sleep decreased. It appears that it doesn’t really matter how long they slept — in fact those with higher tau levels took plenty of naps and slept longer at night yet woke up tired — but the amount of slow wave sleep.
what does that mean for patients?
If subsequent studies show the same correlation between poor quality sleep in patients 60 and older, primary care doctors could include questions about duration and quality of sleep in their checklists and ask them to use a portable EEG monitor to record their brain waves during the night. Based on the results they get back, they can order subsequent tests to help catch early signs of the disease before its symptoms start manifesting themselves and start preventative treatment. After all, the sooner you catch a complex disease, the more options you have to treat it and the more effective that treatment will be.
See: Lucey B.P., et al., Reduced non-rapid eye movement sleep is associated with tau pathology in early Alzheimer’s disease. Science Translational Medicine. Jan. 9, 2018. DOI: 10.1126/scitranslmed.aau6550