Chronodisruption, Glucose and Lipid Metabolism, Shift Work Disorder
Conditions
Keywords
Shift work, Circadian clocks, Nutrition, Glucose metabolism, Lipid metabolism
Brief summary
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.
Detailed 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.
Interventions
None listed
Sponsors
Olga Ramich (formerly Pivovarova)
Charite University, Berlin, Germany
Study design
Observational model
CASE_CONTROL
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to 67 Years
Healthy volunteers
Yes
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 diagnosed conditions, e.g., diabetes mellitus, liver or kidney disease (e.g., cirrhosis of the liver or kidney disease with a GFR \< 60), heart attack within the last 6 months, stroke, or systemic infections; current cancer or cancer diagnosed within the last 2 years * Bariatric surgery * Hereditary or acquired blood clotting disorders * severe mental health conditions, e.g., substance use disorders, eating disorders, or uncontrolled depression (individual assessment by study staff, if necessary following consultation with a physician) * 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 * Specific drug therapies that could influence the study results, e.g., antidiabetic medications including GLP-1 analogs, melatonin (Individual assessment by study staff, if necessary after consultation with a physician) * Implanted electronic medical devices, e.g., pacemakers or neurostimulators (to be assessed on a case-by-case basis by study staff, following consultation with a physician if necessary) * Physical or mental difficulties in understanding and following instructions from study staff
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Mean 24-hour glucose levels and mean night glucose levels | 2 weeks | Mean 24-hour glucose \[mg/dl\] and mean night glucose \[mg/dl\] assessed by continuous glucose monitoring (CGM) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Body weight | 2 weeks | Body weight \[kg\], as measured by scale weight |
| Body Mass Index (BMI) | 2 weeks | BMI \[kg/m2\], calculated as weight/square height |
| Blood pressure | 2 weeks | Systolic and diastolic blood pressure \[mm Hg\], as measured by manometer |
| Glycemic variability | 2 weeks | Inter- and intraday indices of glycemic variability assessed by CGM |
| Eating time | 2 weeks | Timing of all eating events \[hh:mm\] as assessed by food records |
| Calorie intake | 2 weeks | Calorie intake \[kcal\] as assessed by food records |
| Food composition | 2 weeks | Nutrient composition \[EN%\] as assessed by food records |
| Subjective sleep quality | 2 weeks | Sleep quality as assessed by the Pittsburgh Sleep Quality Index (PSQI score, which ranges from 0-21, where higher values correspond to worse sleep quality) |
| Objective sleep quality | 14 days | Sleep quality as assessed by the ActLumus device |
| Sleep timing | 14 days (sleep diary) | Sleep timing (sleep onset and offset \[hh:mm\]) as monitored using a sleep diary |
| Body temperature | 2 weeks | Body temperature is monitored continuously across the entire 24-hour cycle for two weeks by an ActLumus device |
| Light exposure | 2 weeks | Light exposure is monitored continuously across the entire 24-hour cycle for two weeks by an ActLumus device |
| Physical activity | 2 weeks | Physical activity is monitored continuously across the entire 24-hour cycle for two weeks by an ActLumus device |
| Concentration of liver enzymes | 2 weeks | γ-glutamyltransferase (GGT), aspartate aminotransferase (ALT) and alanine aminotransferase (AST) assessed in blood plasma |
| Concentration of lipids | 2 weeks | Total cholesterol, high-density lipoprotein and low-density lipoprotein cholesterol and triglycerides assessed in blood plasma |
| Concentration of kidney parameters | 2 weeks | Creatinine, urea and uric acid assessed in fasting blood samples |
| Glucose concentration | 2 weeks | Glucose levels \[mg/dl\] assessed in fasting blood samples |
| HbA1C concentration | 2 weeks | HbA1C \[%\] assessed in blood samples |
| Insulin concentration | 2 weeks | Levels of insulin assessed using ELISA in serum samples |
| Cortisol concentration | 2 weeks | Levels of cortisol assessed in blood serum |
| Thyroid-stimulating hormone (TSH) concentration | 2 weeks | Levels of TSH assessed in blood serum |
| Leptin concentration | 2 weeks | Levels of leptin assessed in blood serum |
| Concentration of C-reactive protein (CRP) | 2 weeks | CRP assessed in blood serum |
| Concentration of interleukin-6 (IL-6) | 2 weeks | IL-6 assessed in blood serum |
| Gene expression in blood cells | 2 weeks | Whole blood transcriptome assessed by RNAseq |
| Internal circadian phase | 2 weeks | Circadian phase as assessed using the HairTime assay in hair samples |
| Chronotype | 2 weeks | Chronotype will be determined using the Munich ChronoType Questionnaire (MCTQ) , with scores ranging from 16 to 86. Lower scores indicate extreme late chronotypes, while higher scores indicate extreme early chronotypes |
Countries
Germany
Contacts
CONTACTOlga Ramich, Prof. Dr.
CONTACTAnna Merckens
Outcome results
None listed