Sleep and Circadian Treatments for Shift Workers
Overview
- Phase
- Not Applicable
- Intervention
- Not specified
- Conditions
- Shift-Work Sleep Disorder
- Sponsor
- Brigham and Women's Hospital
- Enrollment
- 33
- Locations
- 1
- Primary Endpoint
- Total Sleep Time (TST)
- Status
- Terminated
- Last Updated
- 8 months ago
Overview
Brief Summary
There are three components to this study: a Field Trial, a Shift Worker Survey, and Focus Groups. The Investigators will study the effectiveness, feasibility, and acceptability of an 8-h sleep intervention in older night workers in an operational environment. The overall goal of the Field Trial is to minimize sleep deficiency and negative outcomes resulting from that, including sleepiness and performance impairments during night shift work. The Shift Worker Survey is designed to understand some of the demographic and operational factors that enable or inhibit the ability of individual shift workers to adopt this intervention. The Focus Groups are designed to glean in-depth information from older shift workers who indicate that they are unable or unwilling to adopt an 8-h sleep timing intervention. Understanding these factors will assist in refining and targeting the intervention to those individuals who will be most likely to benefit from the intervention sleep timing strategy.
Detailed Description
The overall goal of the Field Trial is to minimize sleep deficiency and negative outcomes resulting from that, including sleepiness and performance impairments during night shift work. The experimental protocol is divided into two blocks, the Baseline block and the Intervention block, where participants will work at least 3 night shifts in a row within each block. For at least one week prior to the baseline block participants will work their usual shift schedule (i.e., no vacation/scheduled days off). The investigators will recruit up to 200 health care workers in order to have up to 75 health care workers complete the entire Field Trial. Potential participants will be employed older health care workers who work a minimum number of 8-h night shifts per month and who are in the greater Boston area. The Shift Worker Survey is designed to understand some of the demographic and operational factors that enable or inhibit the ability of individual shift workers to adopt the sleep intervention that will be tested in the Field Trial. The investigators will use a web-based survey consisting of \~70 questions developed and administered using REDCap. The complete questionnaire will take approximately 20-30 minutes to complete. The study will enroll up to 1,000 employed individuals (20 or more hours per week) whose work includes overnight shifts, with a minimum criterion of at least 4 night shifts a month. Health Care Workers who complete the Shift Worker Survey will be given the option to complete an additional Health Care Worker's Questionnaire at the end of the basic Shift Worker Survey. Those whose responses meet inclusion/exclusion criteria for the Field Trial will be informed at the end of the Shift Worker Survey that they may be eligible for the Field Trial. The goal of the Focus Groups is to gain information on the feasibility and acceptability of the fixed 8-h sleep schedule from the participants' perspective. Investigators will seek to learn more information about the current sleep strategies they use on a regular basis, and both the facilitating and challenging aspects of the fixed-sleep countermeasure (e.g., individual, intrapersonal and organizational barriers to implementation of fixed 8-h sleep, recommended modifications to the fixed 8-h sleep schedule that would make it more user-friendly while maintaining scientific validity). Each of the focus groups will consist of 4-6 individuals to stimulate discussion without leaving participants out, and will last 60-90 minutes. The investigators aim to enroll up to 60 individuals in Focus Groups. In addition to the health care workers who took part in the Field Trial, the investigators will invite night shift workers who complete the Shift Worker Survey but indicate their inability to comply with a fixed 8-h sleep schedule to attend a Focus Group discussion.
Investigators
Jeanne Duffy
Principal Investigator
Brigham and Women's Hospital
Eligibility Criteria
Inclusion Criteria
- •Age 50-65 years
- •Health care workers who work a minimum of 4 night shifts (8-4) per month
- •Must live in the greater Boston area
- •Must report an ability to work three successive 8-h night shifts during two weeks
- •Must report an ability to spend 8 consecutive hours in bed attempting to sleep prior to the final two successive night shifts in the second study week
- •Must have a typical commute time between home and place of work of less than one hour
Exclusion Criteria
- •Non-optional activities that would interfere with the participant's ability to remain in bed attempting to sleep if randomized to an 8-h sleep group
- •Prescription or over-the-counter medication(s) known to affect sleep \[e.g., hypnotics\] or alertness \[e.g., antihistamines\]
Outcomes
Primary Outcomes
Total Sleep Time (TST)
Time Frame: The TST averaged for up to 3 intervention nights (in minutes) will be compared between groups.
TST is calculated as minutes of sleep in the main sleep episode between shifts, derived from actigraphy data collected in 60 s epochs. The investigators will use a commercial software package to score the sleep. For control group participants who will sleep ad-lib, TST will be calculated for the major sleep episode but also will be summed across sleep episodes if they sleep in more than one bout.
Sleep Fragmentation Index (FI)
Time Frame: The FI averaged for intervention nights 2 and 3 will be compared between groups.
FI will be calculated as the number of times that sleep was terminated after 1 minute, expressed as a percentage of total estimated sleep time, using actigraphy data and commercial software to calculate it.
Wake After Sleep Onset (WASO)
Time Frame: The WASO averaged for intervention nights 2 and 3 will be compared between groups.
WASO is an objective sleep quality measure and will be calculated as the duration (in minutes) of all awakenings during the main sleep episode measured with actigraphy, and calculated using commercial software.
Sustained Attention
Time Frame: PVT mean of slowest 10% of responses measured at the start of the final night shift (night shift 3) during the intervention block will be compared between groups.
The psychomotor vigilance task (PVT) is a test of visual reaction time (RT) in which the participant is asked to maintain the fastest possible RTs to a simple visual stimulus for several minutes. The inter-stimulus interval varies randomly between 2-10 seconds. While there are a number of standard performance metrics that can be obtained from each PVT, we have looked at the slowest 10% of responses.
Subjective Energy
Time Frame: Subjective Energy measurements taken at the end of the final night shift (night shift 3) in the intervention block will be compared between groups.
A Visual Analogue Scale (VAS) will be used to assess subjective energy level. The VAS consists of a 100mm horizontal line with each end of the line labeled with the extremes of a subjective continuum, e.g. energetic-sluggish. The Participant indicates a position on the line that best describes how they feel at that moment. Distance from the left end of the scale (0) to the indicated point will be measured in mm and reported as subjective energeticness. Thus, scores on the scale range from 0 to 100 with lower scores indicating greater subjective energy.
Subjective Sleep Quality
Time Frame: Subjective Sleep quality (refreshment) averaged for intervention nights 2 and 3 will be compared between groups.
Participants will report their subjective sleep quality daily upon awakening from the main sleep episode. Multiple measures of subjective sleep quality will be assessed, but the investigators will report how refreshed the participant feels after awakening as the outcome. This is rated on a 7-point scale, where 7 is the best and 1 is the worst.
Subjective Alertness Via Karolinska Sleepiness Scale (KSS)
Time Frame: The KSS score taken at the end of the final night shift (night shift 3) during the intervention block will be compared to that at baseline.
Participants will complete the Karolinska Sleepiness Scale (KSS) as a measure of subjective alertness immediately following each night shift. The KSS is a Likert scale ranging from 1, extremely alert, to 9, extremely sleepy.
Subjective Health Via Visual Analog Scale (VAS)
Time Frame: Subjective Health via VAS measurements taken at the end of the final night shift (night shift 3) in the intervention block will be compared between groups.
Visual Analogue Scales (VAS) will be used to assess subjective health. VAS consist of a 100mm horizontal line with each end of the line labeled with the extremes of a subjective continuum, e.g. healthy-sick. The Participant indicates a position on the line that best describes how they feel at that moment. Distance from the left end of the scale (0) to the indicated point will be measured in mm and reported as Subjective Health. Thus, scores on the scale range from 0 to 100 with lower scores indicating greater subjective health.
Subjective Stress Via Visual Analog Scale (VAS)
Time Frame: Subjective Stress via VAS measurements taken at the end of the final night shift (night shift 3) in the intervention block will be compared between groups.
A Visual Analogue Scale (VAS) will be used to assess subjective stress.The VAS consists of a 100mm horizontal line with each end of the line labeled with the extremes of a subjective continuum, e.g. relaxed-stressed. The Participant indicates a position on the line that best describes how they feel at that moment. Distance from the left end of the scale (0) to the indicated point will be measured in mm and reported as Subjective Stress. Thus, scores on the scale range from 0 to 100 with higher scores indicating greater subjective stress.
Subjective Calmness Via Visual Analog Scale (VAS)
Time Frame: Subjective Calmness via VAS measurements taken at the end of the final night shift (night shift 3) in the intervention block will be compared between groups.
A Visual Analogue Scale (VAS) will be used to assess subjective Calmness. The VAS consists of a 100mm horizontal line with each end of the line labeled with the extremes of a subjective continuum, e.g. calm-excited. The Participant indicates a position on the line that best describes how they feel at that moment. Distance from the left end of the scale (0) to the indicated point will be measured in mm and reported as Subjective Calmness. Thus, scores on the scale range from 0 to 100 with lower scores indicating greater subjective calmness.
Subjective Alertness Via Visual Analog Scale (VAS) - DATA NOT COLLECTED
Time Frame: Subjective Alertness via VAS measurements taken at the end of the final night shift (night shift 3) in the intervention block will be compared between groups.
Participants will complete the Visual Analog Scale (VAS) as a measure of subjective alertness three times per night shift: Once just before the night shift, once during their shift break, and once immediately following the night shift. The VAS consists of a 100mm horizontal line with each end of the line labeled with the extremes of a subjective continuum, e.g. sleepy-alert. Participants will indicate a position on the line that best describes how they feel at that moment. Distance from the left end of the scale to the indicated point will be measured in mm and reported as Subjective Alertness with higher scores indicating greater subjective alertness.
Secondary Outcomes
- Fatigue and Inter-Shift Recovery(OFER15 scores from the end of the third night shift in the Baseline to the end of the Intervention block will be compared between groups.)
- Subjective Stress(Subjective stress will be assessed immediately after the third night shift in the Baseline and Intervention blocks and the change will be compared between groups.)
- Subjective Quality of Life: WHOQOLBref(WHOQOL-Bref will be taken at Baseline and immediately after the third night shift in the Intervention block and will be compared between groups.)
- Salivary Cortisol Level NOTE THAT THIS AIM WAS DROPPED WHEN THE STUDY WENT TO FULLY REMOTE DUE TO COVID(Salivary Cortisol will be assessed immediately after the third night shift in the Intervention block and levels will be compared between groups.)