NCT05955729

Brief Summary

Night shift work is well known to cause health disruption in short and long term. It has been reported that among healthcare workers, nurses slept less than 6 h/24h. Consequences of such short sleep duration has been associated to long term issues such as endothelial dysfunction associated with cardiovascular diseases, arterial hypertension and type 2 diabetes. Countermeasures such as nap at work has potential effects on reducing the prevalence of cardiovascular diseases. However, to our knowledge, no studies have objectively investigated the effects of napping on endothelial function in a longitudinal design. Therefore, this study aims to investigate the effect of a 30 minutes on-duty nap during night work for 12 weeks on caregivers endothelial dysfunction.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
80

participants targeted

Target at P50-P75 for not_applicable

Timeline
Completed

Started Feb 2024

Typical duration for not_applicable

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

June 23, 2023

Completed
28 days until next milestone

First Posted

Study publicly available on registry

July 21, 2023

Completed
7 months until next milestone

Study Start

First participant enrolled

February 19, 2024

Completed
1.6 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

September 26, 2025

Completed
3 months until next milestone

Study Completion

Last participant's last visit for all outcomes

December 22, 2025

Completed
Last Updated

January 13, 2026

Status Verified

January 1, 2026

Enrollment Period

1.6 years

First QC Date

June 23, 2023

Last Update Submit

January 12, 2026

Conditions

Keywords

NapEndothelial functionShift workNurses

Outcome Measures

Primary Outcomes (1)

  • Evolution of reactive hyperemia index (RHI)

    RHI is measured through the EndoPAT device® initially and at 12 weeks, and corresponds to the vascular reactivity following a 5-min occlusion on an arm

    Change between week 1 and 12

Secondary Outcomes (13)

  • Evolution of pulse wave velocity (PWV)

    Change between week 1 and 12

  • Evolution of blood pressure

    Change between week 1 and 12

  • Evolution of heart rate variability (HRV)

    Change between week 1 and 12

  • Evolution of pro-inflammatory biomarkers

    Change between week 1 and 12

  • Evolution of blood markers of endothelial function

    Change between week 1 and 12

  • +8 more secondary outcomes

Study Arms (2)

Nap group

EXPERIMENTAL

The experimental group will be allocated to do a 30-min on-duty nap during night work, in a dedicated room between 1 am and 4 am.

Behavioral: On-duty NapDevice: EndoPATDevice: Popmeter®Device: Panasonic EW3109Device: ECG HolterBiological: Fasting blood sampleOther: Pichot fatigue scaleOther: French version of the Recovery Needs Scale (BRD)Other: The Short-Form 36 (SF-36)Other: Pittsburgh Sleep Quality Index (PSQI)Other: Epworth questionnaireOther: The Karolinska Sleepiness ScaleDevice: Actimeter

Control group

ACTIVE COMPARATOR

The control group will be allocated to rest in a dedicated room without napping between 1 am and 4 am.

Behavioral: Control condition (30-min rest)Device: EndoPATDevice: Popmeter®Device: Panasonic EW3109Device: ECG HolterBiological: Fasting blood sampleOther: Pichot fatigue scaleOther: French version of the Recovery Needs Scale (BRD)Other: The Short-Form 36 (SF-36)Other: Pittsburgh Sleep Quality Index (PSQI)Other: Epworth questionnaireOther: The Karolinska Sleepiness ScaleDevice: Actimeter

Interventions

The tool is connected to the caregiver's finger and toe via photodiode sensors. Its simple operation enables reproducible measurement of the propagation speed of the pulse wave in 14 seconds.

Control groupNap group

Diastolic and systolic blood pressure measured 3 times in succession using an automatic blood pressure monitor (Panasonic EW3109) in the sitting position on the left arm.

Also known as: automatic blood pressure device
Control groupNap group

The Holter takes an ECG during the subject's daily activities at home.

Also known as: portable electrocardiogram
Control groupNap group

15 ml blood sample (venous sampling) will be taken to measure inflammatory biomarkers (hsCRP, IL-6 TNF-α, IL-1β) and blood markers of endothelial function (NO, CRP, SOD, IL-18).

Control groupNap group

The Pichot fatigue scale is an 8-item questionnaire, with a score above 22 indicating excessive fatigue.

Control groupNap group

BRD questionnaire consists of 11 items coded 0 or 1. A score is calculated for each participant, multiplied by 10 to give a score ranging from 0 to 100. The greater the need for recovery, the higher the score.

Control groupNap group

The SF-36 questionnaire is used to assess quality of life. It comprises 8 sub-scores ranging from 0 (minimum quality of life) to 100 (maximum well-being).

Control groupNap group

24-question sleep quality assessment scale, a score \> 5 indicates poor sleep quality

Control groupNap group

8-question sleepiness assessment scale, a score above 10 indicates excessive sleepiness

Control groupNap group

The Karolinska Sleepiness Scale measures daytime sleepiness on a 9-point scale, based on 5 states and 4 intermediate states that are not verbally indicated.

Control groupNap group
ActimeterDEVICE

An actimeter will be worn on the non-dominant wrist, uninterrupted day and night, for 7 consecutive days.

Control groupNap group
On-duty NapBEHAVIORAL

For 12 weeks, an opportunity for a 30-minute nap during the night shift, between 1 a.m. and 4 a.m., in a quiet room with facilities for lying down.

Nap group

For 12 weeks, an opportunity for a 30-minute rest during the night shift, between 1 a.m. and 4 a.m., in a quiet room without facilities for lying down or napping.

Control group
EndoPATDEVICE

The EndoPAT device® measures vascular reactivity after a 5-minute occlusion on one arm. This device measures changes in vascular tone induced by the endothelium at fingertip level using a pair of plethysmographic sensors. The measurement consists of performing a reference recording for 5 minutes on the 2 arms, then a test arm is chosen to perform an occlusion for 5 minutes while continuing the recording.

Control groupNap group

Eligibility Criteria

Age18 Years - 65 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Being a paramedical caregiverr (nurse or care assistant) at Saint-Etienne University Hospital
  • Be aAged between 18 and 65
  • Working at least 80% of a full-time equivalent post
  • Working 12-hour shifts (day/night) in continuous care services
  • Being affiliated or entitled under a social security scheme
  • Havinge received informed information about the study and have co-signed, with the investigator, a consent to participate in the study

You may not qualify if:

  • Have made a tTrans meridian journey in the last month prior to the study
  • Have a mMedically diagnosed sleep disorder such asof the hypersomnia or insomnia type
  • Have a diagnosed and treated mental pathology
  • Usually take a nap in the workplace in a quiet room
  • Be pregnant or breastfeeding
  • Have medically diagnosed neurovascular or neuromuscular pathologies

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Chu de Saint-Etienne

Saint-Etienne, 42055, France

Location

Related Publications (1)

  • Bouchou Y, Monnier M, Roche F, Pelissier C, Berger M. Effect of 12 weeks with a 30-min nap opportunity during the night shift of healthcare workers on early cardiovascular risk biomarkers: the NAPWORK study protocol of a randomised controlled trial. BMJ Open. 2026 Jan 22;16(1):e110108. doi: 10.1136/bmjopen-2025-110108.

MeSH Terms

Interventions

RE1-silencing transcription factorElectrocardiography, Ambulatory

Intervention Hierarchy (Ancestors)

ElectrocardiographyHeart Function TestsDiagnostic Techniques, CardiovascularDiagnostic Techniques and ProceduresDiagnosisElectrodiagnosisMonitoring, AmbulatoryMonitoring, Physiologic

Study Officials

  • Frédéric ROCHE, MD PhD

    Centre Hospitalier Universitaire de Saint Etienne

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
NONE
Purpose
PREVENTION
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

June 23, 2023

First Posted

July 21, 2023

Study Start

February 19, 2024

Primary Completion

September 26, 2025

Study Completion

December 22, 2025

Last Updated

January 13, 2026

Record last verified: 2026-01

Data Sharing

IPD Sharing
Will not share

Locations