Poor sleep increases vulnerability to colds
Arch Intern Med 2009;169:62-7 [Arch Intern Med Abstract]
Sleeping badly makes you tired, but does it make you ill? To find out, researchers recruited 153 healthy volunteers who agreed to be quarantined for five days and inoculated with the cold virus RV-39. Most of them were infected (135/153; 88%), as defined by isolation of the virus from nasal lavage or development of neutralising antibodies. Only 54 (35%) caught a cold with objective symptoms and signs, but the researchers found a significant association between clinical illness and poor sleep in the two weeks before exposure. People who slept less than seven hours a night were particularly susceptible (odds ratio 2.94, 95% CI 1.18 to 7.30, relative to those who slept eight hours or more). So were inefficient sleepers—people who spent less than 92% of their time in bed actually asleep (5.5, 2.08 to 14.48 relative to more than 98% sleep efficiency). The link between catching a cold and poor sleep efficiency was independent of more than a dozen possible confounders, including an unhealthy lifestyle, obesity, and stress. The researchers conclude that poor sleep probably does make people more susceptible to colds.
Arch Intern Med 2009;169:62-7 [Arch Intern Med Abstract]
Sleeping badly makes you tired, but does it make you ill? To find out, researchers recruited 153 healthy volunteers who agreed to be quarantined for five days and inoculated with the cold virus RV-39. Most of them were infected (135/153; 88%), as defined by isolation of the virus from nasal lavage or development of neutralising antibodies. Only 54 (35%) caught a cold with objective symptoms and signs, but the researchers found a significant association between clinical illness and poor sleep in the two weeks before exposure. People who slept less than seven hours a night were particularly susceptible (odds ratio 2.94, 95% CI 1.18 to 7.30, relative to those who slept eight hours or more). So were inefficient sleepers—people who spent less than 92% of their time in bed actually asleep (5.5, 2.08 to 14.48 relative to more than 98% sleep efficiency). The link between catching a cold and poor sleep efficiency was independent of more than a dozen possible confounders, including an unhealthy lifestyle, obesity, and stress. The researchers conclude that poor sleep probably does make people more susceptible to colds.
