Analysis of Microbiota Variations in Industry Workers Working Different Shifts and Impact of a Nutritional Intervention

Shift workers are a growing population. It is well established that these workers face an increased risk of developing chronic diseases, but the underlying mechanisms remain debated. Various factors such as internal circadian desynchronization, unhealthy lifestyle behaviours, and lack of sleep interact in complex ways. Recently, it has been suggested that the gut microbiota (GM) may play an important role in this increased risk.

The goal of this study is to describe the variations of the GM composition in shift workers across three different rotating weekly shifts (morning, afternoon, night) and to measure the impact of a 3- week walnuts supplementation intervention consisting in a controlled experimental study.

Therefore, we propose a 6-weeks study including an observational and an experimental part. First, in the observational part, we will compare the gut microbiota of shift workers across three shifts (morning, afternoon and night). In the second part of the study, participants will add to their usual intakes a daily serving of nuts (30g). Again, we will compare the gut microbiota composition across the three types of shifts. During the study, participants will record their food intake, sleep and defecation time. We will also monitor their blood glucose levels continuously during the 4 first weeks of the study.

Study Overview

• Status: Active, not recruiting
• Conditions: Dysbiosis
• Intervention / Treatment: Dietary supplement: Walnuts

• Study Type: Interventional
• Enrollment (Anticipated): 18
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Switzerland
  • Carouge
    • Geneva, Carouge, Switzerland, 1227
      • School of Health Sciences Geneva

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: Male

Description

Inclusion Criteria:

• Working 3x8 shifts (weekly rotations between AM, PM and N shifts) for at least 3 months prior to the study
• No anticipated changes in shift work planning
• No prebiotics or probiotics supplements.

Exclusion Criteria:

• Antibiotic and/or immunomodulator use in the last 3 months or during the study
• Change in medication during the last month or during study
• Inflammatory bowel disease or important gut surgery
• Nuts allergy
• Major digestive tract surgery.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: N/A
• Interventional Model: Sequential Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Intervention walnuts; During the 3 last weeks of the study, the participants will eat a 30g daily walnut serving	Dietary supplement: Walnuts; 30g of plain walnuts in addition to habitual food intakes

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in gut microbiota composition between the first and last day of each type of shift (observation phase)	Change in relative abundance of bacteria phyla between the first and last day of each type of shift (AM, PM, N). Assessed by 16S rRNA sequencing approach.	3 weeks (6 measurements over time)
Change in gut microbiota composition between the first and last day of each type of shift (observation vs intervention)	Change in relative abundance of bacteria phyla between the first and last day of each type of shift (AM, PM, N). Assessed by 16S rRNA sequencing approach.	6 weeks (12 measurements over time)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Area under the blood glucose curve between each type of shift	Area under the blood glucose curve between each type of shift (AM, PM, N). Measured using a continuous glucose monitoring.	3 weeks
Area under the blood glucose curve in AM shift (observation vs intervention)	Area under the blood glucose curve during the morning shift (AM) during the observation and the intervention. Measured using a continuous glucose monitoring.	week 1 vs 4

Other Outcome Measures

Outcome Measure	Time Frame
Mean weekly frequency of defecation between each type of shift	6 weeks

Collaborators and Investigators

• Sponsor: Sophie Bucher Della Torre
• Collaborators: University Hospital, Geneva

Study record dates

Study Major Dates

• Study Start (Actual): April 12, 2021
• Primary Completion (Actual): March 31, 2022
• Study Completion (Anticipated): September 30, 2022

Study Registration Dates

• First Submitted: June 2, 2021
• First Submitted That Met QC Criteria: June 2, 2021
• First Posted (Actual): June 9, 2021

Study Record Updates

• Last Update Posted (Actual): May 16, 2022
• Last Update Submitted That Met QC Criteria: May 12, 2022
• Last Verified: May 1, 2022

More Information

Terms related to this study

• Keywords: Gut microbiota
• Additional Relevant MeSH Terms: Pathologic Processes; Dysbiosis
• Other Study ID Numbers: G700136106018

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: De-identified individual participant data for all primary and secondary outcome measure will be made available.
• IPD Sharing Time Frame: Data will be available within 12 months of study completion
• IPD Sharing Access Criteria: At the end of the project the data will be deposited in the Yareta repository developed by the University of Geneva OR in an institutional repository. This choice will ensure that data is archived and shared in accordance with FAIR principles.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No