Short sleep times and disruption of sleep continuity can affect susceptibility to infectious diseases. However, the scientific studies conducted so far have been based on subjective sleep assessments, which could affect the accuracy of the results.

The aim of a study in the United States was to determine whether sleep measured by actigraphy * could be considered as a predictor of the incidence of a cold after experimental viral exposure.

The study voluntarily involved 164 healthy men and women between the ages of 18 and 55. The study did not include patients with chronic conditions and anamnestic data on previous nose surgery. The actigraphy and the sleep diaries evaluated the duration of sleep and its continuity over 7 consecutive days. The study participants were then isolated, injected with nasal drops containing rhinovirus, and they were observed for 5 days for the development of clinical colds (appearance of objective signs of the disease). Samples obtained during washing of the nasopharynx were sent for bacteriological examination for the microbiological diagnosis of the infection. In addition, 28 days after exposure to the virus, blood samples were taken to determine the repeated level of antibodies to the rhinovirus.

About 75% of the participants were infected with the virus and almost one in three patients (29.3%) had clinical symptoms of the disease and the infection was diagnosed.

During a logistic regression analysis, it was found that a shorter sleep duration increased the likelihood of developing a cold. Thus, in individuals whose sleep duration was less than 5 hours (odds ratio 4.5, 95% confidence interval 1.08-18.69) or varied from 5 to 6 hours (OR 4.24, 95% CI 1.08 -16.71), there was a higher risk of developing a cold compared to participants who slept more than 7 hours each night (p = 0.011). This relationship did not depend on the initial antibody titer, age, other demographic characteristics, time of year, body mass index, psychological variables, income level, education and a number of other parameters. The violation of the continuous nature of sleep did not affect sensitivity to rhinovirus.

Thus, this work has shown that a shorter sleep duration leads to an increased sensitivity to colds.

According to researchers, in our incredibly busy world, many people try to do as much work as possible and do not care how long they sleep, and it is dreams that are an essential component of well-being.