In a new study, researchers found that a person's sleeping habits can predict the accumulation of Alzheimer's pathology protein in the brain later in life.
A team from the University of California, Berkeley linked decrease in slow oscillations and sleep spindle synchronization on electroencephalogram (EEG) to higher tau. Meanwhile, reduced slow-wave-activity amplitude was associated with higher Aβ levels.
Sleep And Alzheimer's
The paper published in The Journal of Neuroscience used the data of 101 cognitively normal adults from the longitudinal Berkeley Aging Cohort Study. A subset of 31 participants took the sleep EEG assessment while 95 participants completed a retrospective questionnaire that evaluated lifespan sleep duration and sleep quality change.
The EEG data revealed that the severity of impaired slow oscillation-sleep spindle coupling was linked to greater medial temporal lobe tau burden. The researchers, however, did not see significant associations with Aβ.
Impairments in 0.6-1Hz slow-wave-activity, meanwhile, predicted cortical Aβ, but not tau in the medial temporal lobe or any cortical regions.
Upon analysis of self-reported changes in sleep duration, the researchers noticed that sleep patterns across lifespans predicted Aβ and tau burden later in life.
"This finding may suggest that decreasing sleep duration in mid to late life is significantly associated with an increased risk of late-life Aβ burden, and that a profile of maintained (or even subtle increase) in sleep duration throughout this time period is statistically associated with a reduced predicted risk of Aβ accumulation in late life," the researchers wrote.
Changes in the sleep pattern, as well as the accumulation of tau and proteins in the brain, emerge among patients before memory impairment, the characteristic symptom of Alzheimer's. While the study is limited by a small sample size, the researchers hope that the findings could aid in determining when targeted sleep treatment is most effective.
"If validated in larger longitudinal studies, these sleep-sensitive windows would have the potential to be included in public health recommendations with the goal shifting from a model of late-stage Alzheimer's disease treatment to earlier-life Alzheimer's disease prevention," they stated.
According to the Centers for Disease Control and Prevention, as of 2014, 5 million Americans live with Alzheimer's Disease. A previous study predicted that the number of people diagnosed with the disease could double by 2060.
There is still no cure for Alzheimer's.