“It’s the fifth time you’ve fallen asleep in class today! You need to pay more attention!” the teacher says. However, what they do not know is that the student had been sleeping for less than two hours a night for quite some time. The student had overcommitted himself and had no time for anything, let alone sleep. Sound familiar?
Well, it might be time to reconsider those decisions. Sleep has been shown in countless studies to cause a variety of negative short-term effects like decreased mental capabilities, decreased memory formation, increased emotionality, and a weakened immune system, among many others.
Those all sound bad enough, right? However, there are other, more significant long-term effects to watch out for. Recent studies have shown dementia to be significantly correlated with a lack of sleep. As much as a 1% decrease in sleep each night has been associated with upwards of a 27% increase in chance of developing dementia when over 60 years old.
Dementia (Major Neurocognitive Disorder) is a large growing health concern, especially in the United States and it is estimated that every 3 seconds, someone in the world develops dementia. Dementia is associated with a severe loss of cognitive function usually associated with damage and death of neurons. It has a variety of different forms such as Alzheimer’s, Lewy Body Dementia, and vascular dementia. Each form of dementia has a variety of different causes. Alzheimer’s disease is caused by the formation of amyloid plaques and neurofibrillary tangles in neurons leading to degeneration. Lewy Body Dementia is formed by accumulation of Lewy bodies that are aggregates of alpha-synuclein. Vascular dementia is caused specifically by cardiovascular issues such as hypertension. These are just a few of the conditions associated with dementia, but they make it clear that this is a rising field and set of issues.
America also has a chronic sleep problem that is intimately connected with high levels of dementia. Around 1/3 of Americans report having experienced sleep deprivation in their life. Sleep deprivation is especially common with those experiencing anxiety, insomnia, or a variety of other conditions.
In a correlational study by the NIH’s National Institute on Aging, receiving less than 7 hours of sleep a night between the ages of 50-70 years old was associated a 30% increase in the occurrence of dementia some point in later life. Alternate factors such as mental health issues, heart disease, diabetes, and many other factors were controlled to limit possible confounds within this experiment. However, significantly more research is required to adequately explain the relationships.
One theory that proposes to explain this is the formation of beta amyloid plaques. Beta amyloid is generated within the brain during the day before being removed by cleaning processes that occur during sleep. Without adequate sleep to allow these processes to occur, the beta amyloid proteins build up within the brain and form the beta amyloid plaques specifically found in people with impaired brain function and Alzheimer’s.
While none of this has been supported to a causational level, this data is still disconcerting. Perhaps that lack of sleep you are experiencing is doing more harm than you may have imagined.
King Lab at Creighton University 