DENTON (UNT), Texas -- Many hospitals require employees to get yearly flu vaccinations, to protect patients from contracting the flu and to reduce the number of sick days that employees use.
If employees are sleep deprived, however, could their immune responses to a vaccine be negatively affected?
Two University of North Texas health psychologists will determine if sleep patterns act as a stressor on the immune system -- and possibly lead to reduced response to the vaccine, which could result in greater risk of contracting the flu.
Daniel Taylor, professor of psychology and director of UNT's Sleep and Health Research Laboratory, and Kimberly Kelly, associate professor of psychology and researcher in psychosocial immunology, received a $2.2 million Research Project from National Institutes of Health for a three-year study of flu vaccine effectiveness in nurses. The study will involve 400 nurses recruited from the Denton Regional Medical Center.
"We're mainly concerned about sleep duration, circadian rhythms and sleep efficiency," Taylor said.
Certain sleep patterns, he said, may suppress immune functioning and may reduce the effectiveness of the yearly flu vaccine.
"Many healthcare workers, like nurses, have significant sleep difficulties, and thus may have inadequate influenza vaccine response," he said.
Taylor and Kelly will track the nurses during the 2017-18 flu season. Before receiving their flu shots in early fall 2017, the nurses will be given smartphone applications to complete questionnaires twice a day -- at the start of their day just after awakening and at the end of their day before sleeping. They will describe when they went to bed, how quickly they fell asleep, how often they woke when they needed to sleep, and how much they felt rested when they started their day. In addition, the nurses will answer questions about their stress levels during their workdays and at other times, and note when they changed from day to night shifts, which altered the times they slept.
The nurses will complete the questionnaires for one week before and one week after receiving their flu shots. They also will have their blood drawn before getting the vaccines so the researchers can measure their antibody levels. The nurses will have additional blood draws one month, six months and 12 months after receiving the vaccines to determine antibody response to the strains of flu in the vaccine.
Taylor and Kelly previously tracked healthy college students with and without chronic insomnia -- defined as difficulty sleeping at least three nights a week, despite adequate opportunity to sleep -- after they were vaccinated for the 2011-12 and 2012-13 flu seasons.
They determined that, compared to the students without insomnia, the students with chronic insomnia had lower overall antibody amounts for the H1N1 virus -- which in 2009 had impacted 15- to 29-year-olds with 4.8 times the rate of infection as those older than 60. The students with insomnia also had lower antibodies for the two other flu strains in the vaccine, leading the researchers to conclude that otherwise healthy individuals suffering from insomnia may be more vulnerable to contracting the flu, even after being vaccinated. The study was published in the Journal of Behavioral Sleep Medicine.