Good sleep can be elusive. Many of us are kept awake by too much caffeine…a stressful lifestyle…or a snoring bed partner.
But lack of sleep is more than just a tiring annoyance. Research shows that regular poor sleep increases your risk of developing diabetes, depression, obesity and cardiovascular disease.
Now: New research has uncovered a link to Alzheimer’s disease. Based on this recent analysis, people who don’t sleep well may be at greater risk of developing Alzheimer’s than sound sleepers. This finding comes on the heels of previous studies also showing that sleep may influence the development (or progression) of Alzheimer’s disease.
Recent finding: Researchers at the University of Wisconsin-Madison recruited 101 people (average age 63) with normal cognitive and memory skills, many of whom had risk factors for Alzheimer’s—for example, many had a parent with the disease or carried a gene, such as the APOE gene, which can increase one’s risk for the disease. Participants answered questions about the quality of their sleep and provided spinal fluid samples that were tested for biological markers of Alzheimer’s.
People who reported that they had worse sleep quality, more sleep problems (such as trouble falling asleep, restless sleep or awakening short of breath or with a headache) and daytime sleepiness had more biological markers for Alzheimer’s in their spinal fluid than people who did not have sleep problems.
Those biological markers included signs of amyloid and tau proteins that are related to the plaques and tangles found in the brains of people with Alzheimer’s disease. The study also looked for other biological markers in the spinal fluid, including signs of brain cell damage and inflammation. The results remained the same when researchers adjusted for other factors such as the use of sleep medication, level of education, depression symptoms and body mass index.
Not every person with sleep problems had abnormalities in his/her spinal fluid. For example, the study found no link between self-reporting of obstructive sleep apnea and biological markers for Alzheimer’s.
“Disrupted sleep or lack of sleep may lead to amyloid plaque buildup because the brain’s clearance system really seems to kick into action during sleep,” explained Barbara B. Bendlin, PhD, the study’s lead author. In other words, in the absence of sleep, amyloid may deposit more quickly because it’s not being cleared from the brain.
“However, we can’t tell from this study if it’s the case that disrupted sleep is causing amyloid to build up in the brain, or if it’s the other way around, where changes in the brain associated with Alzheimer’s are affecting the quality of sleep,” she said.
Implications: While more research is needed to further define the relationship between sleep and Alzheimer’s, the identification of modifiable risk factors for the disease is important given estimates that suggest delaying the onset of this disease in people by just five years could reduce the number of cases seen in the next 30 years by 5.7 million…and could save $367 billion in health-care spending in the US.
Bottom line: Improved sleep in at-risk people may prevent or delay the onset of Alzheimer’s disease. Whether you are at increased risk for Alzheimer’s disease or not, if you feel that you need better-quality sleep, be sure to talk to your doctor about strategies that may help.
Editor’s note: If you’re having trouble getting a good night’s sleep, here are some innovative fixes for sleep problems.