Improving Cancer-Related Outcomes in Shift Workers (ICOS)

Shift work with circadian disruption has been linked with increased breast cancer incidence. The mechanisms for this effect are not yet completely understood.

This study evaluates the impact of a previously developed sleep intervention in shift workers at risk of breast cancer; and assesses mediating variables that may explain the relationship between shift work and breast cancer.

A sample of women night shift workers were provided with a sleep intervention. The intervention is a standard approach used in a sleep clinic and is delivered by telephone by a trained intervener.

Hypothesis: The intervention will improve sleep in women night shift workers, which will in turn have a positive impact on biological and behavioural risk factors associated with breast cancer and quality of life.

Study Overview

• Status: Completed
• Conditions: Breast Cancer
• Intervention / Treatment: Behavioral: Sleep intervention

Detailed Description

47 female night shift workers completed a sleep intervention. The intervention follows an established sleep therapy protocol. Assessments at baseline, 6 and 12 months include mammographic density and possible mediating variables known to be linked to breast cancer risk including behavioural, biometric, and biological measures. Behavioural and self-report measures of sleep quality and physical activity are assessed as well as self-reported chronotype and quality of life.

The intervention is a multi-session intervention using cognitive behavioural principles to increase healthy sleep by addressing a variety of behaviours that may influence sleep quality and quantity, based an established telephone-based protocol used at the UBC Hospital Sleep Disorders Clinic. It includes 10 telephone sessions spaced over a 6-month period, and 2 additional booster sessions at 8 and 10 months. Participants are given a sleep diary at baseline to complete for 2 weeks before the sleep hygiene telephone counseling session begins.

The intervention protocol incorporates sleep assessment, maintaining a sleep diary and use of an actiwatch (to measure sleep and physical activity), sleep hygiene (i.e., controlling behavioural and environmental factors that affect sleep), stimulus control therapy (i.e., teaching individuals how to eliminate behaviours that are incompatible with sleep), sleep restriction therapy (i.e., teaching how to limit time in bed to time asleep), cognitive restructuring (i.e., modifying non-adaptive thoughts and triggers for insomnia), and relapse prevention. The structured counseling protocol includes concrete exercises and activities, questions and answers, and problem solving strategies.

Medication use is not part of this protocol; if participants wish to explore pharmacologic approaches, they are advised to consult with their physicians. Although some shift workers have received care from the Sleep Clinic in the past, there has not been a systematic focus on this group.

The project manager conducts a telephone-based evaluation of the intervention 6 months post-sleep intervention. Blood and salivary samples are collected using standardized data collection methods at baseline, 6, and 12 months, and mammographic films are collected at baseline and 12 months.

• Study Type: Interventional
• Enrollment (Actual): 47
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • British Columbia
    • Vancouver, British Columbia, Canada, V6T1Z3
      • University of British Columbia

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 40 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: Female

Description

Inclusion Criteria:

• Women aged 40-65 years
• Working or living in Greater Vancouver Area
• Read and understand English
• Work rotating or permanent night shift at least 3 times per month, for at least 2 years
• Received a screening mammogram within the past 3 years

Exclusion Criteria:

• History of breast cancer
• On active cancer therapy for any cancer
• Pregnant
• Diabetes requiring drug treatment

Study Plan

How is the study designed?

Design Details

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

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Other: Sleep intervention

Behavioral: Sleep intervention; Session 1: Intervener & participant review 2-week sleep diary and actigraph data. Provide individualized sleep hygiene prescription. Session 2: Review sleep diary; calculate sleep efficiency; identify adjustments needed. Session 3: Review sleep-related vs. stress-related symptoms. Develop plan for sleep-related symptoms and discuss "Sleep Restriction with Relaxation Exercises." Session 4: Reinforce progress and make corrections as required. If Sleep Restriction is not working, Stimulus Control is introduced. Session 5-10: Provide reinforcement, assess adherence, answer questions, and offer encouragement and monitoring, including alterations as required. Booster sessions: At 8 & 10 months: reinforcement, question answering, encouragement and monitoring.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in sleep quality	Self-reported "good" sleep quality at baseline and 6 months	Baseline, 6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in melatonin	Change in melatonin at baseline and 6 months	Baseline, 6 months
Change in melatonin	Change in melatonin at 6 and 12 months	6 months, 12 months
Change in melatonin	Change in melatonin at baseline and 12 months	Baseline, 12 months
Change in cortisol	Change in cortisol at baseline and 6 months	Baseline, 6 months
Change in cortisol	Change in cortisol at 6 and 12 months	6 months, 12 months
Change in cortisol	Change in cortisol at baseline and 12 months	Baseline, 12 months
Change in breast density	Change in breast density at baseline and 12 months	Baseline, 12 months
Change in IGF-1 and IGFBP 1,2,3,7	Change in IGF-1 and IGFBP 1,2,3,7 at baseline and 6 months	Baseline, 6 months
Change in IGF-1 and IGFBP 1,2,3,7	Change in IGF-1 and IGFBP 1,2,3,7 at 6 and 12 months	6 months,12 months
Change in IGF-1 and IGFBP 1,2,3,7	Change in IGF-1 and IGFBP 1,2,3,7 at baseline and 12 months	Baseline, 12 months
Change in Vitamin D	Change in Vitamin D at baseline and 6 months	Baseline, 6 months
Change in Vitamin D	Change in Vitamin D at 6 and 12 months	6 months, 12 months
Change in Vitamin D	Change in Vitamin D at baseline and 12 months	Baseline, 12 months
Change in C-reactive protein	Change in C-reactive protein from baseline to 6 months	Baseline, 6 months
Change in C-reactive protein	Change in C-reactive protein from 6 to 12 months	6 months and 12 months
Change in C-reactive protein	Change in C-reactive protein from baseline to 12 months	Baseline, 12 months
Change in insulin	Change in insulin from baseline to 6 months	Baseline, 6 months
Change in insulin	Change in insulin from 6 to 12 months	6 months and 12 months
Change in insulin	Change in insulin from baseline to 12 months	Baseline, 12 months
Change in glucose	Change in glucose from baseline to 6 months	Baseline, 6 months
Change in glucose	Change in glucose from 6 to 12 months	6 months and 12 months
Change in glucose	Change in glucose from baseline to 12 months	Baseline, 12 months
Change in quality of life	Change in quality of life from baseline to 6 months	Baseline, 6 months
Change in quality of life	Change in quality of life from 6 months to 12 months	6 months, 12 months
Change in quality of life	Change in quality of life from baseline to 12 months	Baseline,12 months
Intervention Evaluation	Participant satisfaction and perceptions of intervention assessed by semi-structured telephone interview	12 months
Change in sleep quality	Self-reported "good" sleep quality at 6 and 12 months	6 months, 12 months
Change in sleep quality	Self-reported "good" sleep quality at baseline and 12 months	Baseline, 12 months
Change in health and lifestyle	Change in self-reported health and lifestyle assessed by structured questionnaire at baseline and 6 months	Baseline, 6 months
Change in health and lifestyle	Change in self-reported health and lifestyle assessed by structured questionnaire at 6 and 12 months	6 months, 12 months
Change in health and lifestyle	Change in self-reported health and lifestyle assessed by structured questionnaire at baseline and 12 months	Baseline, 12 months

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Concordance between self-reported sleep quality and other indicators	Comparison of ratings between self-reports, diary data, and actigraph readings at all time points	Baseline, 6 months, 12 months

Collaborators and Investigators

• Sponsor: University of British Columbia
• Collaborators: Canadian Cancer Society (CCS)
• Investigators: Principal Investigator: Carolyn Gotay, PhD., The Univeristy of British Columbia

Study record dates

Study Major Dates

• Study Start: July 1, 2011
• Primary Completion (Actual): April 1, 2015
• Study Completion (Actual): January 1, 2016

Study Registration Dates

• First Submitted: November 17, 2015
• First Submitted That Met QC Criteria: November 18, 2015
• First Posted (Estimate): November 20, 2015

Study Record Updates

• Last Update Posted (Estimate): November 3, 2016
• Last Update Submitted That Met QC Criteria: November 1, 2016
• Last Verified: November 1, 2016

More Information

Terms related to this study

• Keywords: breast cancer; prevention; intervention; sleep hygiene; lifestyle; occupational; biological; shiftwork
• Additional Relevant MeSH Terms: Skin Diseases; Neoplasms; Neoplasms by Site; Breast Diseases; Breast Neoplasms
• Other Study ID Numbers: 2011-701007

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO