Sleep habits and susceptibility to the common cold.
Level 3 - non-randomized controlled study
Prospective cohort study with observational baseline sleep measurement followed by experimental viral inoculation.
PubMed 19139325 · doi:10.1001/archinternmed.2008.505
What was done
Researchers tracked 153 healthy men and women (age 21–55 years) who self-reported their daily sleep duration, sleep efficiency (percentage of time in bed actually asleep), and whether they felt rested across a 14-day baseline. Participants were subsequently quarantined, inoculated with nasal drops containing a rhinovirus, and monitored for 5 days post-exposure for the development of a clinical cold (infection with objective signs of illness).
What was found
A graded association was observed between sleep metrics and cold susceptibility: participants sleeping less than 7 hours were 2.94 times more likely to develop a cold than those sleeping 8 hours or more (95% CI, 1.18–7.30). Participants with sleep efficiency below 92% were 5.50 times more likely to develop a cold than those with 98% or greater efficiency (95% CI, 2.08–14.48). These associations remained after adjusting for prechallenge antibody titers, demographics, season, body mass, socioeconomic status, psychological variables, and health practices. The percentage of days feeling rested was not associated with cold risk.
Why it matters
This study provides prospective evidence using a controlled viral exposure model that shorter sleep duration and poorer sleep efficiency directly correlate with increased susceptibility to upper respiratory viral infection.
Limits
Sleep variables were measured via daily self-report rather than objective polysomnography or actigraphy. The study sample was modest (n = 153) and restricted to healthy adults aged 21–55 exposed to a single rhinovirus strain, which may limit generalizability to older or immunocompromised populations and other respiratory viruses.
Cited by
- supports In a viral challenge study with rhinovirus, subjects with 7 or more hours of sleep and good sleep efficiency had a five- to sevenfold lower risk of developing a cold compared to those with less sleep.