Sleep as a cognitive indicator and other studies presented at AAIC

The Alzheimer’s Association’s International Conference being held this week in Vancouver, British Columbia, Canada, continues to present a wealth of information from international studies on Alzheimer’s and other dementias.

Sleep quantity and quality can indicate cognitive decline

A recent Nurses’ Health Study suggested a relationship between the quality and quantity of sleep and cognitive decline. Interventions to improve sleep may not only improve an individual’s quality of life, but may also reduce or prevent a loss of cognition.

More than 15,000 participants, age 70 or older at their first cognitive exam between 1995 and 2000, participated in a study to investigate the role of sleep in relation to cognitive decline. Researchers at Boston’s Brigham and Women’s Hospital and her colleagues concluded: (1) participants who slept five hours per day or less had lower average cognition than those who slept for seven hours, (2) subjects who slept more than nine hours also had lower average cognition than those who had seven hours of sleep, and (3) too little or too much sleep was cognitively equivalent to aging by two years.

Other potential indicators of cognitive decline found in other studies were sleep disorders, such as sleep apnea, and disruptions in circadian rhythms.

MCI raises the risk of death

In one study Mindy Katz, MPH, and her colleagues at Albert Einstein College of Medicine of Yeshiva University, Bronx, New York analyzed study results and found that people with dementia or amnestic mild cognitive impairment (MCI) had a significantly higher risk of dying than people with normal cognition.

Katz noted in a report: “In our study, amnesticMCI was associated with a doubling of the risk of death. Those people with other types on non-memory thinking difficulties were not at a higher risk of mortality.”