Changes in sleep patterns are common in people with Alzheimer’s disease and other dementias. They may wake up often during the night and find it hard to get back to sleep. These sleep problems are thought to result from brain changes caused by the disease that affect the sleep-wake cycle.

Studies have suggested that sleep patterns earlier in life may contribute to later dementia risk. Both insufficient sleep and sleeping longer than average have been linked to a greater likelihood of developing dementia. However, it has been hard to determine whether these sleep changes contribute to the disease or simply reflect early symptoms.