Overview
The aim of the study is to evaluate circadian glucose, activity and dietary rhythms, as well as metabolic and cardiovascular risk associated with night shift work, sleep quality and well-being in a cohort of hospital staff, comparing employees with night shifts to employees without night shifts.
Description
The parallel-arm study consists of group A of employees working night shifts and group B of employees not working night shifts. After a pre-screening and an inclusion examination, both groups attend their first visit after at least two day shifts before the start of their two-week observation phase. During the visit, anthropometric measurements are conducted, blood and hair samples are collected, and questionnaires are completed and handed out. During the observation period, the 24-hour activity and glucose rhythms of the study participants are measured and the food intake is documented. After an observation phase, group A attends a second visit after at least two night shifts, including blood and hair sample collection.
Eligibility
Inclusion Criteria:
- Aged between 18 and 67
- Male or female
- Currently employed
- Body-Mass-Index (BMI) \<40 kg/m2
- Working hours ≥28 hours/week
- Employees working night shifts (group A): (1) Working night shifts for \>1 year, (2) at least two night shifts within the 2-week observation period
- Employees not working night shifts (group B): No night shifts for \>1 year
- Capable of giving consent
- Health insurance
- Good knowledge of German
Exclusion Criteria:
- Pregnancy and breastfeeding
- Special diets, e.g. intermittent fasting
- Severe acute or chronic illnesses, e.g. type 1 diabetes mellitus, liver or kidney disease, heart attack within the last 6 months, stroke or systemic infections, current cancer or cancer within the last 2 years
- Bariatric surgery
- Hereditary or acquired blood clotting disorders
- Severe mental illnesses, e.g. depression, addiction or eating disorders (individual assessment by study staff, if necessary after consultation with a doctor)
- Holiday in a different time zone (≥ 2 hours time difference) one month before study participation or within the 2-week observation phase
- Participation in another study that could influence the results of the current study
- Special drug therapies that could influence the study results (individual assessment by study staff, if necessary after consultation with a physician)
- Physical or mental difficulties in understanding and following instructions from study staff


