ST. LOUIS — A new study has linked poor quality sleep to higher levels of a brain protein believed to cause Alzheimer's.<br /><br />Researchers from the Washington University School of Medicine studied the link between tau and sleep levels by recruiting 119 people over 60, most of whom were cognitively healthy.<br /><br />According to the study published in Science Translational Medicine, subjects' sleep patterns were monitored for a week using portable EEG monitors and wristwatch-like sensors.<br /><br />Tau and amyloid beta levels were also measured using either PET brain scans or spinal fluid sampling.<br /><br />The results show that those who had fewer hours of slow-wave sleep had higher volumes of the tau protein in their brain.<br /><br />Slow-wave sleep is the deepest phase of non-rapid eye movement sleep. This stage of the sleep cycle is also thought to be important for memory consolidation.<br /><br />According to study author Brendan Lucey, those who showed increased tau pathology slept more at night and napped during the day, but were not getting good quality sleep.<br /><br />While the findings are significant, the study is unclear on whether poor quality sleep is a cause or consequence of pathological changes in the brain.<br /><br />Researchers suggest, however, that sleep disruptions may be an effective tool for doctors to spot patients in the earliest stages of cognitive decline.
