Older people who have trouble sleeping may experience immune system inflammation that leaves them vulnerable to other neurological conditions, according to a report recently published in the American Journal of Geriatric Psychiatry.
The study, conducted by the University of Rochester Medical Center, shows a much higher level of markers associated with systemic inflammation in older people who sleep poorly than in those of the age who sleep well. The study used a sample of 83 people who averaged 61 years of age.
To prepare, the participants were given a self-reporting questionnaire to evaluate sleep quality, perceived stress, and medication use. Twenty-seven percent of the respondents were considered poor sleepers. On the day of the study, participants were given a battery of math and verbal questions to serve as a stressor.
Blood samples taken immediately before and after the stress test and at intervals for 60 minutes following were tested for interleukin-6. IL-6 is a protein that appears at sites of inflammation within the body. The poor sleeper group generally reported more depression and more perceived stress than the good sleeper group, but both groups' levels of IL-6 were equivalent prior to the test.
After experiencing stress, both groups' IL-6 levels spiked, but the increase for poor sleepers was much larger than for the good sleepers, sometimes as much as a 400 percent increase. This raised it to a level previously associated with increased risk of illness and death in the age group tested.
Controlling for other factors, including loneliness and the role of depression in a person's life did not substantially alter IL-6 levels, indicating that quality sleep alone was the sole differentiating factor.
Source: The University of Rochester