Cold and flu linked to sleep quality
A newly-published US study has provided evidence to support the link between good-quality sleep and the ability to fight off colds and flu.
Researchers based at Carnegie Mellon University in Pittsburgh infected healthy subjects with the cold-causing rhinovirus and compared the outcomes to sleep data compiled over the previous two weeks.
153 men and women, with an average age of 37, took part in the study between 2000 and 2004. In the first stage, participants were interviewed daily about sleep and wake times, disturbances to sleep and how rested they felt. By dividing reported sleep duration by time spent in bed, researchers were able to calculate a ‘sleep efficiency’ value for each individual.
After infection, participants remained in quarantine for five days where they reported their symptoms and delivered samples to researchers. Finally, 28 days after exposure, subjects provided blood samples which were analysed for antibody content.
In results published in the Archives of Internal Medicine, researchers reported that subjects who spent less than 92 percent of their time in bed sleeping were five and a half times more likely to develop cold symptoms than those who slept for 98 percent of their bed time.
They also found that those who got less than seven hours of sleep per night were around three times more likely to succumb to the infection than those who slept for eight hours or more.
Findings of the study are held to be consistent with previous investigations of sleep impact on immune response.
sources: BBC, The Guardian