Night Shift Work and Biomarkers of Obesity Risk in Hospital and Industry Workers

Recruiting

• Conditions: Obesity; Shift-work Disorder; Circadian Rhythm Disorders
• Interventions: Other: No intervention

• Registration Number: NCT06288568
• Lead Sponsor: University of Vienna

Brief Summary

Shift work is a well-known risk factor for the development of overweight and obesity, which may lead to downstream effects such as increased risk of cardiometabolic diseases and cancer. However, the biological and behavioral mechanisms underlying the obesogenicity of night shift work are not well understood. Population-based mechanistic studies in real life shift workers are needed to address how night shift work impacts metabolic health.

The investigators aim to characterize the behavioural, environmental, and biological mechanisms and pathways for the association of night shift work and obesity across Europe.

The investigators will conduct a cross sectional study in 5 European countries (Austria, Denmark, Germany, Netherlands and Poland) and recruit 1000 rotating night shift workers and day workers (200/country) from the health sector and different industries. Night and day workers will be age-frequency (3 age groups), gender and (where possible) working tasks matched. Participants will complete online questionnaires and report their diet habits in a mobile app. Body composition, dietary behavior and sensory preferences will be tested. Biologic specimens (blood, urine, saliva, hair and feces) will be collected at the workplace on a day where participants are working on a day shift (or a day off). In a subsample (Austria and Netherlands) shift workers will provide biological samples (spot blood, urine and saliva) both on a day shift and on a night shift. Biomarkers including hormones, cellular immunity and inflammation, parameters linked to gut health and metabolism of fat and sugar, appetite, oxidative stress, metabolomics and microbiota will be measured. The investigators hypothesize that compared to day workers, night shift workers will experience disrupted levels of pre-obesity markers. Higher circadian disruption, sleep disruption and mistimed eating patterns workers will be associated with more disrupted biomarker profiles. Among rotating shift workers, night shift will be associated with acute disrupted melatonin production, metabolomic profiles and composition of oral microbiota compared to a day shift.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2024-02-23
• Study First Submitted QC: 2024-02-23
• Study First Posted: 2024-03-01
• Study Start: 2024-04-01
• Status Verified: 2025-02
• Last Update Submitted: 2025-02-17
• Last Update Posted: 2025-02-19
• Primary Completion: 2025-11-01
• Study Completion: 2028-05-31

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 1000

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Nightshift workers	No intervention	Nightshift worker in the health care and industrial sector. Night shift is defined as a work schedule that involves working at least 3 hours between 00:00 and 5:00, at least 2 consecutive nights/month.
Dayshift workers	No intervention	Dayshift worker in the health care and industrial sector. No night shifts.

Primary Outcome Measures

Name	Time	Method
high-sensitive C-Reactive Protein (hs-CRP)	Baseline	Compare hs-CRP levels between night shift workers and day shift workers

Secondary Outcome Measures

Name	Time	Method
The investigators will consider levels of hormones in plasma	Baseline	Compare cortisol levels between night shift workers and day shift workers
The investigators will consider parameters of cellular immunity and inflammation in plasma	Baseline	Compare chemokines levels between night shift workers and day shift workers
The investigators will consider levels of oxidative stress in whole blood, serum, plasma and urine	Baseline	Compare unconjugated bilirubin levels between night shift workers and day shift workers
The investigators will consider metabolomics analysis of plasma samples and dry blood spots (DBS)	Baseline	Compare the levels of various metabolites between night shift workers and day shift workers
The investigators will consider parameters of metabolism of fat and sugar in plasma	Baseline	Compare glucose levels between night shift workers and day shift workers
The investigators will consider microbiome analysis of feces samples and tongue swabs	Baseline	Compare the levels of various microbiota composition between night shift workers and day shift workers
The investigators will consider levels of appetite markers in plasma	Baseline	Compare ghrelin levels between night shift workers and day shift workers
The investigators will consider levels of parameters linked to gut health in serum and in feces	Baseline	Compare zonulin-1 levels between night shift workers and day shift workers

Trial Locations

Locations (1)

Medical University of Vienna; 🇦🇹 Vienna, Austria