A good night’s sleep may help with various concerns, but a new study reveals that getting enough sleep may also lessen your vulnerability to sickness.
Researchers recruited medical students from the University of Bergen to distribute short questionnaires to patients on recent illnesses and sleep quality. They found that individuals with chronic sleep problems were more likely to report requiring antibiotics and having recently had an illness and to report sleeping too much or too little. “Most previous observational studies have looked at the association between sleep and infection in a sample of the general population,” said Dr Ingeborg Forthun, corresponding author of the study published in Frontiers in Psychiatry. “We wanted to assess this association among patients in primary care, where we know that the prevalence of sleep problems is much higher than in the population at large.”
Existing evidence suggests that sleep disturbances increase the risk of infection. In prior research, those intentionally infected with rhinovirus who reported adequate sleep were less likely to get a cold. Sleep disturbances are common and treatable. If a relationship between illness and its underlying mechanism can be established, it can reduce antibiotic usage and protect patients from infections before they occur. Yet experimental research can’t duplicate real-life settings.
Forthun and her colleagues provided medical students with a questionnaire and urged them to distribute it to patients in the waiting rooms of the general practitioners’ offices where the students were employed. One thousand eight hundred forty-eight surveys were collected across Norway. People were asked to describe their sleep quality, including how long they generally slept, how well they felt they slept when they preferred to sleep, and if they had had any illnesses or had taken antibiotics during the preceding three months. In addition, the survey included a scale for identifying instances of chronic insomnia disorder.
The scientists found that patients who reported sleeping less than six hours a night were 27 per cent more likely to report an infection, while patients sleeping more than nine hours were 44 per cent more likely to register one. Less than six hours of sleep, or chronic insomnia, also raised the risk of needing an antibiotic to overcome an infection.
“The higher risk of reporting an infection among patients who reported short or long sleep duration is not that surprising as we know that having an infection can cause both poor sleep and sleepiness,” said Forthun. “But the higher risk of an infection among those with a chronic insomnia disorder indicates that the direction of this relationship also goes in the other direction; poor sleep can make you more susceptible to an infection.”
Although there was some potential for bias in the sense that people’s recall of sleep or recent health issues is not necessarily perfect, and no clinical information was collected from the doctors who subsequently saw the patients, the study design allowed for the collection of data from a large study group experiencing real-world conditions.
“We don’t know why the patients visited their GPs, and it could be that an underlying health problem affects both the risk of poor sleep and infection, but we don’t think this can fully explain our results,” said Forthun.
She continued: “Insomnia is very common among patients in primary care but found to be under-recognized by general practitioners. Increased awareness of the importance of sleep, not only for general well-being but also for patients’ health, is needed among patients and general practitioners.”