Poor Sleep Tied to Brain Changes of Dementia

Poor sleep in older adults may be linked to brain changes associated with dementia, a new study has found.

Researchers studied 167 men who underwent sleep tests in 1999 and died by 2010. The study, in Neurology, recorded sleep duration, periods of waking up and episodes of apnea, and used pulse oximetry to measure oxygen saturation of their blood.

On autopsy, they found that those in the highest one-quarter for duration of sleep at oxygen saturation of less than 95 percent were almost four times as likely to have higher levels microinfarcts, small areas of dead tissue caused by deprivation of blood supply, as those in the lowest one-quarter.

Compared with those in the lowest 25 percent for duration of slow-wave (deep) sleep, those in the highest one-quarter were about a third as likely to have moderate or high levels of generalized brain atrophy.

“Prior studies have shown an association between certain types of sleep disturbance and dementia,” said the lead author, Dr. Rebecca P. Gelber, an epidemiologist with the Veterans Administration in Hawaii. “These lesions may help explain the association.”