“Social jetlag,” the time difference experienced between sleep patterns on days off compared to work days, has emerged as an important marker for health, according to University of Arizona Health Sciences sleep researchers.
Social jet lag occurs when there is a discrepancy between your body’s internal clock and your sleep schedule exemplified by sleeping shorter times during the week and sleeping longer but staying up later during the weekend.
The research team was led by senior author Michael A. Grandner, PhD, director of the Sleep and Health Research Program and assistant professor of psychiatry, psychology and medicine at the University of Arizona. Dr. Grandner was principal investigator for the community-based sleep survey known as the SHADES study (Sleep and Health Activity, Diet, Environment and Socialization), conducted in Philadelphia at the University of Pennsylvania. The study’s preliminary findings showed that each hour of social jet lag was associated with an 11-percent increase in the likelihood of heart disease. Social jet lag, the study found, also was associated with poorer health, worse mood and increased sleepiness and fatigue.
“It was particularly surprising that these effects were independent of how much sleep people got and any insomnia symptoms. These results indicate that sleep regularity, beyond sleep duration alone, plays a significant role in our health,” said lead author Sierra B. Forbush, an undergraduate research assistant in the Sleep and Health Research Program at the UA College of Medicine – Tucson.
Forbush presented the findings today at the annual meeting of the Associated Professional Sleep Societies, being held June 3-7 in Boston. The meeting is a joint venture of the American Academy of Sleep and the Sleep Research Society.
Forbush and the research team members analyzed the sleep responses provided by 984 adults, ages 22 to 60, from the SHADES study. Funded by the National Institutes of Health, the SHADES study was funded to gain better understanding about sleep as it relates to health, behavior and the physical environment, including poverty rates, crime statistics, noise and traffic.
Social jet lag was calculated by subtracting the weekday and weekend sleep midpoint using the SHADES study Sleep Timing Questionnaire. Overall health was self-reported using a standardized scale with survey questions on sleep duration, insomnia, cardiovascular disease, fatigue and sleepiness.
The research abstract was published recently in an online supplement of the journal Sleep.
Dr. Grandner is supported by the National, Lung and Blood Institute (K23HL110216) and the SHADES study was supported by the National Institute of Environmental Health Sciences (R21ES022931).
Abstract Title: Sociodemographics, Poor Overall health, Cardiovascular Disease, Depression, Fatigue, and Daytime Sleepiness Associated with Social Jetlag Independent of Sleep duration and Insomnia.
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