Breast Cancer
Conditions
Keywords
shiftwork, sleep hygiene, prevention, intervention, occupational, biological, breast cancer, lifestyle
Brief summary
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.
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.
Interventions
BEHAVIORALSleep 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.
Sponsors
Canadian Cancer Society (CCS)
University of British Columbia
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
PREVENTION
Masking
NONE
Eligibility
Sex/Gender
FEMALE
Age
40 Years to 65 Years
Healthy volunteers
Yes
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in sleep quality | Baseline, 6 months | Self-reported good sleep quality at baseline and 6 months |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in melatonin | Baseline, 6 months | Change in melatonin at baseline and 6 months |
| Change in cortisol | Baseline, 6 months | Change in cortisol at baseline and 6 months |
| Change in breast density | Baseline, 12 months | Change in breast density at baseline and 12 months |
| Change in IGF-1 and IGFBP 1,2,3,7 | Baseline, 6 months | Change in IGF-1 and IGFBP 1,2,3,7 at baseline and 6 months |
| Change in Vitamin D | Baseline, 6 months | Change in Vitamin D at baseline and 6 months |
| Change in C-reactive protein | Baseline, 6 months | Change in C-reactive protein from baseline to 6 months |
| Change in glucose | Baseline, 6 months | Change in glucose from baseline to 6 months |
| Change in quality of life | Baseline, 6 months | Change in quality of life from baseline to 6 months |
| Intervention Evaluation | 12 months | Participant satisfaction and perceptions of intervention assessed by semi-structured telephone interview |
| Change in sleep quality | 6 months, 12 months | Self-reported good sleep quality at 6 and 12 months |
| Change in health and lifestyle | Baseline, 6 months | Change in self-reported health and lifestyle assessed by structured questionnaire at baseline and 6 months |
| Change in insulin | Baseline, 6 months | Change in insulin from baseline to 6 months |
Other
| Measure | Time frame | Description |
|---|---|---|
| Concordance between self-reported sleep quality and other indicators | Baseline, 6 months, 12 months | Comparison of ratings between self-reports, diary data, and actigraph readings at all time points |
Countries
Canada
Outcome results
None listed