Health News: Poor Sleep Prior to Rhinovirus Exposure Leads to Reduced Resistance to the Common Cold

Poorer sleep efficiency and shorter sleep duration in the weeks before exposure to a rhinovirus are linked to greater susceptibility to the common cold, according to the results of a study reported in the January 12 issue of the Archives of Internal Medicine.

The study sample consisted of 153 healthy men and women volunteers aged 21 to 55. For 14 days, subjects reported their sleep duration and sleep efficiency, defined as percentage of time in bed actually asleep for the previous night and whether they felt rested. The investigators calculated average scores for each sleep variable during the 14-day baseline. Participants were then quarantined, inoculated with nasal drops containing a rhinovirus, and monitored for the development of a clinical cold on the day before and for 5 days after rhinovirus exposure. Clinical cold was defined as infection in the presence of objective signs of illness.

Participants who reported less than 7 hours of sleep were nearly 3 times more likely to get a cold than those with 8 hours or more of sleep, suggesting a correlation with average sleep duration. Participants with less than 92% sleep efficiency were 5.5 times more likely to get a cold than those with 98% or more efficiency, also suggesting a correlation with sleep efficiency.

So, your mother was right -- you need to get plenty of sleep!

Arch Intern Med. 2009;169:62-67.

Term of the Day

Hypersomnia Sleep Apnea (HSA) Syndrome: Periodic breathing and episodes of apnea (absence of air flow for at least 10 seconds during sleep) associated with stage I and II and REM sleep. Decreased arterial oxygen saturation leads to arousal, thus interrupting the sleep cycle and leading to sleep and REM deprivation. HSA syndrome is mainly the result of upper airway obstruction occurring during sleep. Patients may experience hundreds of episodes of apnea per night, which leads to extreme daytime sleepiness. Snorting and thrashing about during sleep are common, and some patients may experience sleepwalking or enuresis.