[h=1]Less Sleep Means Smaller Brains in Older Adults[/h]
As a former raging insomniac cured by light therapy, the new findings about shorter sleep correlating with brain aging caught my eye. For years, we’ve been warned that not getting enough sleep negatively impacts long term health – e.g. increased risk of obesity, diabetes, heart disease, hypertension, mood disorders; decreased immune function; higher prevalence of alcohol use; and associations with lower life expectancy. Those are all health correlates, however, so researchers have been searching for biomarkers that provide a link between sleep and brain aging. Biomarkers are measurable indicators of a biological condition that link a specific environmental exposure (in this case, less sleep) to a health outcome (brain aging). Indeed, past studies have demonstrated that brain ventricular volume and enlargement serve as biomarkers for Alzheimer’s disease and its progression. This new study adds evidence for the link between sleep and cognitive performance.
wikimedia.org
Just in case you’re not sure, let’s pause and explain the ventricular system: The cerebral ventricles are interconnected spaces in the brain and brainstem that are filled with cerebrospinal fluid, colored purple and red in the diagram to the left and indicated by green arrows in the brain MRIs below.
health-advisors.org, uic.edu
Published in the current issue of the journal SLEEP, researchers at Duke-NUS Graduate Medical School Singapore performed a longitudinal study that examined the effects of sleep on brain ventricle enlargement, a marker of cognitive decline. They used MRI and neuropsychological assessments every 2 years on 66 adults to investigate the correlation between ventricle enlargement and cognitive ability; questionnaires were used to record the amount of sleep. For every hour of decreased sleep, annual results showed an incremental increase in ventricular enlargement and an incremental decrease in cognitive performance.
Dr. June Lo, the lead author and a Duke-NUS Research Fellow summarized the study: “Our findings relate short sleep to a marker of brain aging.” Professor Michael Chee, senior author and Director of the Centre for Cognitive Neuroscience at Duke-NUS added, “Work done elsewhere suggests that seven hours a day for adults seems to be the sweet spot for optimal performance on computer based cognitive tests. In coming years we hope to determine what’s good for cardio-metabolic and long term brain health too.”
All participants came from the Singapore Longitudinal Aging Brain Study. An interesting follow-up study would be to do the same on a younger population of adults and to augment validity by including adults from different backgrounds. I would expect to basically have the same results (perhaps with a lower percentage of expansion and decline); right now, this study is telling me that I don’t really have to care about sleep and my “brain age” until I’m 55 years old, which is certainly not true. Nevertheless, these findings are not only relevant in the context of Singapore’s rapidly aging society, but also pave the way for future research on sleep loss and its effects on cognitive decline, including alzheimer’s and dementia.
So go ahead and catch some Z’s! Your brain will thank you for it.
Less Sleep Means Smaller Brains in Older Adults | Atom's Apple
As a former raging insomniac cured by light therapy, the new findings about shorter sleep correlating with brain aging caught my eye. For years, we’ve been warned that not getting enough sleep negatively impacts long term health – e.g. increased risk of obesity, diabetes, heart disease, hypertension, mood disorders; decreased immune function; higher prevalence of alcohol use; and associations with lower life expectancy. Those are all health correlates, however, so researchers have been searching for biomarkers that provide a link between sleep and brain aging. Biomarkers are measurable indicators of a biological condition that link a specific environmental exposure (in this case, less sleep) to a health outcome (brain aging). Indeed, past studies have demonstrated that brain ventricular volume and enlargement serve as biomarkers for Alzheimer’s disease and its progression. This new study adds evidence for the link between sleep and cognitive performance.
“Though faster brain ventricle enlargement is a marker for cognitive decline and the development of neurodegenerative diseases such as Alzheimer’s, the effects of sleep on this marker have never been measured.”
wikimedia.org
Just in case you’re not sure, let’s pause and explain the ventricular system: The cerebral ventricles are interconnected spaces in the brain and brainstem that are filled with cerebrospinal fluid, colored purple and red in the diagram to the left and indicated by green arrows in the brain MRIs below.
health-advisors.org, uic.edu
Published in the current issue of the journal SLEEP, researchers at Duke-NUS Graduate Medical School Singapore performed a longitudinal study that examined the effects of sleep on brain ventricle enlargement, a marker of cognitive decline. They used MRI and neuropsychological assessments every 2 years on 66 adults to investigate the correlation between ventricle enlargement and cognitive ability; questionnaires were used to record the amount of sleep. For every hour of decreased sleep, annual results showed an incremental increase in ventricular enlargement and an incremental decrease in cognitive performance.
“Each hour of reduced sleep duration at baseline augmented the annual expansion rate of the ventricles by 0.59% and the annual decline rate in global cognitive performance by 0.67% in the subsequent 2 years, after controlling for the effects of age, sex, education, and body mass index.”
In healthy older adults who are at least 55 years old, less sleep was associated with greater age-related brain atrophy and cognitive decline. In very simple terms, not getting enough sleep decreases brain mass and increases the volume of those fluid-filled spaces in the above diagrams. Since you have less brain mass to work with, you don’t do as well on cognitive tests as you would if your brain had not lost any mass.
Dr. June Lo, the lead author and a Duke-NUS Research Fellow summarized the study: “Our findings relate short sleep to a marker of brain aging.” Professor Michael Chee, senior author and Director of the Centre for Cognitive Neuroscience at Duke-NUS added, “Work done elsewhere suggests that seven hours a day for adults seems to be the sweet spot for optimal performance on computer based cognitive tests. In coming years we hope to determine what’s good for cardio-metabolic and long term brain health too.”
All participants came from the Singapore Longitudinal Aging Brain Study. An interesting follow-up study would be to do the same on a younger population of adults and to augment validity by including adults from different backgrounds. I would expect to basically have the same results (perhaps with a lower percentage of expansion and decline); right now, this study is telling me that I don’t really have to care about sleep and my “brain age” until I’m 55 years old, which is certainly not true. Nevertheless, these findings are not only relevant in the context of Singapore’s rapidly aging society, but also pave the way for future research on sleep loss and its effects on cognitive decline, including alzheimer’s and dementia.
So go ahead and catch some Z’s! Your brain will thank you for it.
Less Sleep Means Smaller Brains in Older Adults | Atom's Apple
