Behaviorally Assessed Sleep and Susceptibility to the Common Cold.
Level 3 - non-randomized controlled study
Prospective cohort study with experimental viral challenge (sleep exposure was observational, not randomized).
PubMed 26118561 · doi:10.5665/sleep.4968
What was done
A total of 164 healthy men and women aged 18 to 55 wore wrist actigraphs and kept sleep diaries for 7 consecutive days to assess sleep duration and continuity. Participants were then quarantined, challenged with nasal drops containing rhinovirus, and monitored over 5 days for the development of a clinical cold (defined as infection combined with objective signs of illness). Logistic regression models evaluated whether actigraphy-assessed sleep predicted cold incidence, adjusting for prechallenge antibody levels, demographics, season, body mass index, psychological factors, and health practices.
What was found
Actigraphy-measured shorter sleep duration significantly predicted cold development relative to sleeping > 7 h per night: sleeping < 5 h resulted in an OR of 4.50 (95% CI, 1.08–18.69) and sleeping 5 to 6 h resulted in an OR of 4.24 (95% CI, 1.08–16.71). Sleeping 6.01 to 7 h was not associated with significantly higher risk (OR = 1.66, 95% CI, 0.40–6.95). Sleep fragmentation and other diary or actigraphy variables were not strong predictors of cold susceptibility.
Why it matters
This study provides prospective, objective behavioral evidence linking short sleep duration directly to biological susceptibility to viral respiratory infection, demonstrating that the relationship persists after controlling for baseline antibody levels and other confounding factors.
Limits
The sample size of 164 healthy volunteers resulted in wide confidence intervals for odds ratios. Sleep was assessed over a single 7-day period prior to quarantine, which may not capture long-term baseline patterns. Because sleep duration was observed rather than experimentally manipulated, residual confounding remains possible.
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.