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Updated: Jun 2, 2026
10:16
Human Circadian Phenotyping and Diurnal Performance Testing in the Real World
Published on: April 7, 2020
Shift work in nurses: contribution of phenotypes and genotypes to adaptation
Karen L Gamble1, Alison A Motsinger-Reif, Akiko Hida
1Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, United States of America.
Plos One
|May 3, 2011
Summary
Shift work disrupts daily biological rhythms, increasing health risks. Adaptation depends on sleep strategies, individual chronotype, and circadian clock gene variations, impacting nurse health and healthcare policy.
Area of Science:
- Chronobiology
- Occupational Health
- Genetics
Background:
- Shift work disrupts circadian rhythms, increasing risks for metabolic, cardiovascular, and mental health disorders.
- The specific roles of sleep timing, chronotype, and circadian clock gene variations in shift work adaptation remain unclear.
Purpose of the Study:
- To investigate how sleep strategies, chronotype, and circadian clock gene polymorphisms influence adaptation to shift work.
- To identify factors contributing to poor adaptation in shift workers.
Main Methods:
- Assessed sleep strategies, chronotype, and polymorphisms in circadian clock genes (CLOCK, NPAS2, PER2, PER3) in 388 hospital nurses.
- Analyzed associations between genetic variations, chronotype, sleep behaviors, and adaptation to day/night shifts.
Main Results:
- Nurses using sleep deprivation to adjust sleep were least adapted.
- Chronotype significantly affected adaptation efficacy.
- Circadian gene polymorphisms (CLOCK, NPAS2, PER2, PER3) correlated with alcohol/caffeine intake, sleepiness, sleep phase, inertia, and duration, often interacting with shift type.
Conclusions:
- Sleep strategy, chronotype, and genotype are key to adapting the circadian system to irregular schedules.
- Shift work acts as an environmental stressor with significant health consequences, particularly for nurses.
- Findings have implications for healthcare policy regarding shift worker well-being.
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