Cancer, Breast
Conditions
Brief summary
Breast cancer survivors aged 60+ and with overweight/obesity who had completed chemotherapy 1-6 years earlier completed 8 weeks of 12-8 pm weekday-only time-restricted eating. The intervention was delivered by a registered dietitian call, twice-daily automated text messages asking about eating start/stop times, and three support phone calls.
Interventions
BEHAVIORALTime-restricted eating
Restriction of calorie intake to an 8-hour window, with water only fasting in the remaining 16 hours of the 24-hour period
Sponsors
University of Alberta
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
PREVENTION
Masking
NONE
Eligibility
Sex/Gender
FEMALE
Age
60 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* history of early-stage (I-III) breast cancer * completed anthracycline-based chemotherapy 1-6 years earlier * aged ≥60 years * had a body mass index (BMI) \>25 kg/m2
Exclusion criteria
* taking lipid, glucose, or weight-lowering medications * contraindications to maximal exercise testing or research MRI * unstable thyroid disorder * self-reported history of an eating disorder * self-reported diagnosis of type 1 or 2 diabetes * weight loss of ≥15 lbs in previous 3 months * working night shifts * could not provide consent in English
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Framingham 10-year cardiovascular risk score (%) | 8 weeks | Calculated using the Canadian Cardiovascular scoring system |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Visceral adipose tissue | 8 weeks | measured via magnetic resonance fat-water separation imaging |
| Cardiorespiratory fitness | 8 weeks | Measured as peak volume of oxygen consumed collected with a cycle erogmeter exercise test |
| Resting energy expenditure | 8 weeks | Collected via metabolic cart in supine resting position after overnight fast |
| Respiratory quotient | 8 weeks | Collected via metabolic cart in supine resting position after overnight fast |
| Lipid profile | 8 weeks | Collected via analysis of fasting blood sample by Lifelabs commercial laboratory |
| Fasting insulin | 8 weeks | Collected via analysis of fasting blood sample by Lifelabs commercial laboratory |
| Resting systolic and diastolic blood pressure | 8 weeks | measured as the average of two measurements 60 seconds apart following 5-10 minutes of supine rest using an automated device |
| Body mass | 8 weeks | measured by physicians scale after overnight fast |
| Whole-body fat mass | 8 weeks | estimated using8-point bioelectric impedance (Seca) |
| Whole-body fat-free mass | 8 weeks | estimated using8-point bioelectric impedance (Seca) |
| Hemoglobin A1c | 8 weeks | Collected via analysis of blood sample by Lifelabs commercial laboratory |
| Waist circumference | 8 weeks | measured as the average of two measurements to the nearest 0.5 cm. |
| Fasting glucose | 8 weeks | Collected via analysis of fasting blood sample by Lifelabs commercial laboratory |
| Thigh adipose tissue fraction | 8 weeks | Relative measure of amount of inter+intra muscular adipose tissue within the thigh muscle measured via magnetic resonance fat-water separation imaging |
| Liver adipose tissue fraction | 8 weeks | Relative measure of amount of adipose tissue within the liver |
Other
| Measure | Time frame | Description |
|---|---|---|
| Adherence to intervention | Ongoing for duration of intervention | Collected via participant responses to automated text messages asking participants to self-report the time they started and stopped eating each day. Calculated as the % of prescribed days to follow the intervention where participant reported performing a 16 hour or longer fast. |
| Participant acceptability | 8 weeks | assessed by a researcher-developed end of study questionnaire as: 1) a subjective difficulty rating for following TRE on a scale of 1-10 and 2) rating the dietitian and support calls as 'very helpful' or 'somewhat helpful' on a 5-point Likert scale (other options were 'neutral,' 'somewhat helpful,' and 'unhelpful') |
| Intervention fidelity | 8 weeks | determined as completion rates of the intervention components (registered dietitian consult call, the three support calls, and response rate to the text messages) |
| Intervention sustainability | 1 month post intervention | Rate of continuing to follow TRE one-month post-intervention completion (without further support or instructions) collected by phone follow-up |
| Intervention sustainability confidence | 8 weeks | Average subjective rating of confidence, on 0-100% scale, in ability to follow TRE for one year or longer |
| Intervention delivery cost | Through study completion, lasting 12-24 weeks depending on chemotherapy protocol | Estimated as average time spent by personnel on intervention delivery multiplied by the hourly rate for that personnel |
| Symptoms | Through study completion, lasting 12-24 weeks depending on chemotherapy protocol | Collected at each of the support phone calls at weeks 1, 3, 6 of the intervention. The research coordinator asked participants if they experienced any symptoms on a pre-determined list or any additional symptoms. Symptoms were only recorded if the participant reported that they were related to the intervention or were unsure if they were related. Symptoms attributed to other life events (i.e., heat wave, stress at work) were not recorded. |
| Activity | Change between measurement at baseline and 8 weeks | 24-hour Measured via Sensewear Pro accelerometer worn on the arm for 3 consecutive weekdays |
| Dietary intake | 8 weeks | Measured via diet records on 3 consecutive weekdays that were analyzed via Food Processor Nutrition Analysis Software |
Countries
Canada
Outcome results
None listed