MNT: Weight Management (2015)
- To assess the feasibility of a diet and physical activity intervention designed for weight loss or control in breast cancer (BC) survivors through evaluation of participation and compliance rates
- To assess short-term effects of the intervention on diet-related choices, cardiorespiratory fitness (CRF) and quality of life (QOL).
- Patients with breast cancer
- Recently completed chemotherapy or radiation therapy (within six months).
- Previous cancers
- Tumors of stage IIIB and above
- Morbid obesity (BMI 40kg/m2 or more)
- Conditions that prohibit following diet and physical activity (PA).
Medical records of patients who received chemotherapy or radiation for breast cancer at the Catalan Institute of Oncology were reviewed for eligibility. Mailers were sent to invite these individuals to participate.
A Phase II single-arm trial.
- Diet intervention:
- Twelve-week one-hour sessions were led by a dietitian.
- The first half of each session focused on:
- Food groups
- Food guide pyramid
- Making healthy choices
- Hypocaloric meal preparation and cooking (1,200kcal to 1,500kcal per day)
- Shopping lists
- Weekly menus.
- The second half of the sessions were focused on:
- Weight loss goals
- Tools and tips to overcome barriers
- Participation in motivational group activities.
- Physical activity (PA):
- Twenty-four biweekly sessions of 75 minutes each were led by PA monitors.
- Warm-up for 10 minutes followed by two 25-minute session of aerobic (static bike) and strength training exercises (mats, stability balls, resistance bands) followed by a 10-minute stretch and relaxation.
- Participants were encouraged to walk 10,000 steps per day and given a pedometer.
- Shapiro-Wilk's to check for normality
- T-test and Wilcoxon- Mann Whitney to determine differences in continuous outcome variables
- Fisher exact test to assess associations/differences in categorical variables (expected values all less than five)
- Paired T-test and Wilcoxon signed-rank test used to determine differences before and after intervention in continuous normally and non-normally distributed outcome variables, respectively
- Sensitivity analysis for weight change variable using imputation of zero for non-completers.
Timing of Measurements
- Twelve-week intervention
- Assessed over two weeks before and after intervention.
- Primary outcomes:
- Participation: The ratio of the number of women who consented and the number of women who were invited to this study
- Compliance: Number of diet and PA sessions attended divided by the number of sessions offered
- Weight change: Dietitians weighed participants without shoes, at baseline and post-intervention. Goal weight loss was at least three percent of baseline weight.
- Secondary outcomes:
- Changes in macronutrient consumption pattern: Measured using a validated food frequency questionnaire (FFQ) and three 24-hour dietary recalls at baseline and post-intervention
- Changes in CRF: Measured using cycle ergometer to measure VO2Peak and power output at baseline and post-intervention
- Quality of life (QOL): Measured from responses to the European Organization for Research and Treatment of Cancer Core Quality of Life Questionnaire C30 (EORTC QLQ-C30), and a general measure of QOL, the 36-Item Short Form Health Survey (SF-36) at baseline and post-intervention.
Twelve-week diet and PA intervention as described previously.
- Initial N: 112 eligible women, 42 consented
- Attrition (final N): 37 completed (12% attrition)
- Age: 54.8 years (8.7 years), mean (SD).
Other Relevant Demographics
- 34 (81%) married
- 21 (50%) never smoked, 16 (38%) former, 5 (11.9) current
- 25 (59.5%) post-menopausal.
- BMI 30.4 (3.8), mean (SD)
- No significant differences between eligible candidates who participated and eligible candidates who did not participate, save for treatment type.
Catalan Institute of Oncology (Spain).
- Participation rate: 38%
- Attendance (compliance): 92% diet sessions and 91% for PA sessions.
|Weight (kg)||73.3 (10.2)||67.6 (10.1)||-7.8 (2.9)||0.001|
|BMI (kg/m2)||30.5 (3.9)||28.1 (3.9)||-7.8 (2.9)||0.001|
|Energy intake (kcal)||1,903.8 (422.0)||1,387.8 (223.7)||-24.5 (17.2)||0.001|
|Lipids (g)||86.6 (25.0)||52.7 (11.7)||-34.6 (21.3)||0.001|
|Saturated fat (g)||22.2 (8.2)||12.3 (4.6)||-37.0 (31.7)||0.001|
|Protein (g)||74.7 (16.8)||75.6 (14.1)||5.7 (30.8)||0.743|
|Carbohydrate (g)||199.8 (49.4)||151.1 (34.9)||-21.3 (21.9)||0.001|
|Fiber (g)||15.7 (4.6)||16.0 (4.2)||8.2 (33.3)||1.000|
|VO2peak (ml per kg-1 per minute-1)||19.0 (2.8)||24.0 (4.1)||26.7 (16.9)||0.001|
|Peak power output: Body mass
(W per kg-1)
|SF-36: General health||62.2 (16.8)||68.8 (19.7)||13.7 (32.8)||0.017|
|EORTC QLQ-C30: Global health||69.1 (18.1)||79.5 (18.4)||22.0 (42.9)||0.001|
|Macronutrient||Pre-intervention (Percent of kcal)||Post-intervention (Percent of kcal)|
Sensitivity analysis: Significant weight loss of 5.0kg (2.7kg) from baseline.
|Government:||ISCIII (RETICC RD06/0020/0091) of the Spanish Ministry of Health|
- Pre-experimental type study poses threats to internal validity such as lack of control group, randomization and so on. Many confounders could come into play and it is difficult to attribute the positive changes to the intervention alone for this reason. However, this study was designed as a prelude to a larger clinical trial.
- The lack of a control group may have falsely elevated the participation and compliance rates since the consenters knew they had 100% chance of the intervention rather than a 50% if a control group existed. This may have also attracted more highly motivated individuals.
Quality Criteria Checklist: Primary Research
|1.||Would implementing the studied intervention or procedure (if found successful) result in improved outcomes for the patients/clients/population group? (Not Applicable for some epidemiological studies)||Yes|
|2.||Did the authors study an outcome (dependent variable) or topic that the patients/clients/population group would care about?||Yes|
|3.||Is the focus of the intervention or procedure (independent variable) or topic of study a common issue of concern to dieteticspractice?||Yes|
|4.||Is the intervention or procedure feasible? (NA for some epidemiological studies)||Yes|
|1.||Was the research question clearly stated?||Yes|
|1.1.||Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified?||Yes|
|1.2.||Was (were) the outcome(s) [dependent variable(s)] clearly indicated?||Yes|
|1.3.||Were the target population and setting specified?||Yes|
|2.||Was the selection of study subjects/patients free from bias?||Yes|
|2.1.||Were inclusion/exclusion criteria specified (e.g., risk, point in disease progression, diagnostic or prognosis criteria), and with sufficient detail and without omitting criteria critical to the study?||Yes|
|2.2.||Were criteria applied equally to all study groups?||N/A|
|2.3.||Were health, demographics, and other characteristics of subjects described?||No|
|2.4.||Were the subjects/patients a representative sample of the relevant population?||Yes|
|3.||Were study groups comparable?||N/A|
|3.1.||Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT)||N/A|
|3.2.||Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline?||N/A|
|3.3.||Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.)||N/A|
|3.4.||If cohort study or cross-sectional study, were groups comparable on important confounding factors and/or were preexisting differences accounted for by using appropriate adjustments in statistical analysis?||N/A|
|3.5.||If case control study, were potential confounding factors comparable for cases and controls? (If case series or trial with subjects serving as own control, this criterion is not applicable.)||N/A|
|3.6.||If diagnostic test, was there an independent blind comparison with an appropriate reference standard (e.g., "gold standard")?||N/A|
|4.||Was method of handling withdrawals described?||Yes|
|4.1.||Were follow-up methods described and the same for all groups?||Yes|
|4.2.||Was the number, characteristics of withdrawals (i.e., dropouts, lost to follow up, attrition rate) and/or response rate (cross-sectional studies) described for each group? (Follow up goal for a strong study is 80%.)||Yes|
|4.3.||Were all enrolled subjects/patients (in the original sample) accounted for?||Yes|
|4.4.||Were reasons for withdrawals similar across groups?||N/A|
|4.5.||If diagnostic test, was decision to perform reference test not dependent on results of test under study?||N/A|
|5.||Was blinding used to prevent introduction of bias?||N/A|
|5.1.||In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate?||N/A|
|5.2.||Were data collectors blinded for outcomes assessment? (If outcome is measured using an objective test, such as a lab value, this criterion is assumed to be met.)||N/A|
|5.3.||In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded?||N/A|
|5.4.||In case control study, was case definition explicit and case ascertainment not influenced by exposure status?||N/A|
|5.5.||In diagnostic study, were test results blinded to patient history and other test results?||N/A|
|6.||Were intervention/therapeutic regimens/exposure factor or procedure and any comparison(s) described in detail? Were interveningfactors described?||Yes|
|6.1.||In RCT or other intervention trial, were protocols described for all regimens studied?||Yes|
|6.2.||In observational study, were interventions, study settings, and clinicians/provider described?||N/A|
|6.3.||Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect?||Yes|
|6.4.||Was the amount of exposure and, if relevant, subject/patient compliance measured?||Yes|
|6.5.||Were co-interventions (e.g., ancillary treatments, other therapies) described?||Yes|
|6.6.||Were extra or unplanned treatments described?||No|
|6.7.||Was the information for 6.4, 6.5, and 6.6 assessed the same way for all groups?||Yes|
|6.8.||In diagnostic study, were details of test administration and replication sufficient?||N/A|
|7.||Were outcomes clearly defined and the measurements valid and reliable?||N/A|
|7.1.||Were primary and secondary endpoints described and relevant to the question?||Yes|
|7.2.||Were nutrition measures appropriate to question and outcomes of concern?||Yes|
|7.3.||Was the period of follow-up long enough for important outcome(s) to occur?||Yes|
|7.4.||Were the observations and measurements based on standard, valid, and reliable data collection instruments/tests/procedures?||Yes|
|7.5.||Was the measurement of effect at an appropriate level of precision?||Yes|
|7.6.||Were other factors accounted for (measured) that could affect outcomes?||No|
|7.7.||Were the measurements conducted consistently across groups?||N/A|
|8.||Was the statistical analysis appropriate for the study design and type of outcome indicators?||Yes|
|8.1.||Were statistical analyses adequately described and the results reported appropriately?||Yes|
|8.2.||Were correct statistical tests used and assumptions of test not violated?||Yes|
|8.3.||Were statistics reported with levels of significance and/or confidence intervals?||Yes|
|8.4.||Was "intent to treat" analysis of outcomes done (and as appropriate, was there an analysis of outcomes for those maximally exposed or a dose-response analysis)?||N/A|
|8.5.||Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)?||No|
|8.6.||Was clinical significance as well as statistical significance reported?||No|
|8.7.||If negative findings, was a power calculation reported to address type 2 error?||N/A|
|9.||Are conclusions supported by results with biases and limitations taken into consideration?||Yes|
|9.1.||Is there a discussion of findings?||Yes|
|9.2.||Are biases and study limitations identified and discussed?||Yes|
|10.||Is bias due to study's funding or sponsorship unlikely?||Yes|
|10.1.||Were sources of funding and investigators' affiliations described?||Yes|
|10.2.||Was the study free from apparent conflict of interest?||Yes|