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Trial registered on ANZCTR


Registration number
ACTRN12616000658415
Ethics application status
Approved
Date submitted
5/11/2015
Date registered
20/05/2016
Date last updated
20/05/2016
Type of registration
Prospectively registered

Titles & IDs
Public title
Cognitive Remediation Therapy for Obesity
Scientific title
Randomised controlled trial comparing cognitive remediation therapy plus behavioural weight loss compared to behavioural weight loss alone for reducing weight in obese adults with and without binge eating disorder.
Secondary ID [1] 287772 0
Nil
Universal Trial Number (UTN)
Trial acronym
CRTO
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Obesity 296659 0
Binge eating disorder 296930 0
Condition category
Condition code
Diet and Nutrition 296881 296881 0 0
Obesity
Mental Health 297175 297175 0 0
Eating disorders

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
This randomised controlled trial aims to determine the efficacy of manualised Cognitive Remediation Therapy (CRT) in reducing weight and improving executive function in obese patients. Manualised cognitive remediation therapy is a face-to-face treatment approach with a focus on improving cognitive functioning. CRT consists of mental exercises aimed at improving cognitive strategies, thinking skills and information processing through practice (Tchanturia, 2014). The NHMRC guidelines strongly recommend obese individuals lose weight through lifestyle modification interventions. The current standard evidence based approach is Behavioural Weight Loss (BWL), it uses behavioural techniques to help individuals modify eating and exercise habits.

The following conditions will be compared; CRT plus behavioural weight loss (BWL) and BWL (standard care) alone. It is expected that individuals who receive CRT will show greater weight-loss and improved executive functioning than those in the BWL alone, post-treatment and at 1 year follow-up (post-treatment).

Treatment will continue for 5 months and be provided by two psychologists. A dietician will facilitate groups related to the diet component of the BWL program. Participants aged 18 to 55, with a BMI of 30 or above will be randomly allocated to one of two conditions:
1) CRT group: Eight weekly sessions of individual CRT followed by twelve weekly sessions of group Behavioural Weight Loss (BWL)
2) BWL group: Eight weekly sessions of individual BWL followed by twelve weekly sessions of group Behavioural Weight Loss (BWL)

Individual treatment will be conducted before group sessions commence. Twelve participants will be allocated to group treatment.

Description of sessions:
1) CRT group: Eight 50-minute weekly sessions of individual CRT plus twelve 2 hour weekly sessions of group Behavioural Weight Loss (BWL) treatment.

CRT Sessions: During CRT 10 cognitive training exercises will be delivered per session. An example of an exercise is the Map Task - the aim is to think in different ways when navigating and to use different cues (compass, street, location, etc). The psychologist will facilitate a discussion about thinking styles after the completion of tasks. Homework will be given after every session, homework should take about 15 mins to complete.

Behavioural Weight Loss (BWL) Group sessions: During these sessions a modified version of the Look Ahead Trial manual will be delivered. The Look Ahead program is an intensive lifestyle intervention program that targets diet and exercise through behavioural modification techniques. During this program participants will be given weight loss information and be encouraged to set calorie and activity goals. Participants will be asked to monitor and record their behaviour. In the group setting participants are taught techniques such as: problem solving, stress management and mindful eating to assist them to reach their weight loss goals. Thoughts and emotions related to overeating and inactivity are also addressed in treatment sessions.

2) BWL group: Eight 50 minute weekly sessions of individual BWL plus twelve 2 hour weekly sessions of group Behavioural Weight Loss (BWL).
This treatment group will experience an intensive BWL program. The addition of individual sessions will help to examine whether more sessions of BWL are beneficial. The individual sessions of BWL will focus upon providing detailed education about weight loss techniques and addressing any barriers that the participant may have in terms of changing their behaviour.

Intervention code [1] 293166 0
Treatment: Other
Intervention code [2] 293167 0
Behaviour
Comparator / control treatment
The Behavioural Weight Loss Alone Group will be the control group.
Control group
Active

Outcomes
Primary outcome [1] 296485 0
Percentage weight change at post-treatment compared with pre-treatment (baseline) will be the primary outcome, derived from measured body weight. Further, measurement of weight at 1 year follow-up (post-treatment) will inform about treatment effects on early weight loss and on weight loss maintenance.
Timepoint [1] 296485 0
Baseline, post-treatment and 1 year follow-up post-treatment.
Secondary outcome [1] 318577 0
Anthropometric Measures: height & weight (BMI)
Timepoint [1] 318577 0
Baseline, post-treatment and 1 year follow-up post-treatment.
Secondary outcome [2] 318578 0
Neuropsychological Assessment: Targeted assessment of cognitive function. Executive function, memory, speed of information processing, language tests will be conducted.
Assessment of cognitive function will be completed at the participant's prefered time. The following tests will be conducted: Executive function: Trail making test B; Simple Rey Complex Figure task; Wisconsin sorting task; and a composite score. Memory: Logical memory (immediate and delayed); Simple Rey Complex Figure task; Speed of information processing: Trail Making test A; Language: Boston Naming test.

Timepoint [2] 318578 0
Baseline, post-treatment and 1 year follow-up post-treatment.
Secondary outcome [3] 318579 0
Inflammatory Markers used: Tumor necrosis factor-a (TNFa)
interleukin-6 (IL-6), inflammasome-activated IL-1ß
C-reactive protein
Blood will be collected by Sydpath.
Timepoint [3] 318579 0
Baseline, post-treatment and 1 year follow-up post-treatment.
Secondary outcome [4] 318580 0
Demographics: Age, sex, socio-economic status (by postcode, income, education) and language use will be assessed via completion of a self-report questionnaire developed for this study by the research team.
Timepoint [4] 318580 0
Baseline
Secondary outcome [5] 318581 0
Nutrition: Via Foodworks Professional package.
This will be assessed using a self-report (via 3 day food diary) and analysed using Foodworks Professional package.
Timepoint [5] 318581 0
Baseline, post-treatment and 1 year follow-up post-treatment.
Secondary outcome [6] 318582 0
Quality of Life: Assessed via Short Form- 12 Health Status Questionnaire (SF-12)
Timepoint [6] 318582 0
Baseline, post-treatment and 1 year follow-up post-treatment.
Secondary outcome [7] 318583 0
Depression,Anxiety and Stress: Assessed via the DASS scale.
Timepoint [7] 318583 0
Baseline, post-treatment and 1 year follow-up post-treatment.
Secondary outcome [8] 318584 0
Eating Disorder Symptoms: Assessed via the Eating Disorder Examination Questionnaire (EDE-Q).
Timepoint [8] 318584 0
Baseline, post-treatment and 1 year follow-up post-treatment.
Secondary outcome [9] 318585 0
Brief clinical assessment: will verfiy comorbidities such as eating disorder, depression or anxiety.
Timepoint [9] 318585 0
Baseline, post-treatment and 1 year follow-up post-treatment.
Secondary outcome [10] 318586 0
Exercise: Measured via accelerometers. The participant will wear an accelerometer for 3 days in total.
Timepoint [10] 318586 0
To be measured at baseline and post-treatment.
Secondary outcome [11] 318587 0
Comprehensive medical assessment: including history and current medical conditions and medication, including smoking and alcohol intake
Timepoint [11] 318587 0
Baseline
Secondary outcome [12] 318588 0
Compliance with BWL treatment: Attendance to sessions will be monitored by the treating psychologist/dietician.
Timepoint [12] 318588 0
Weekly during treatment (5 months)
Secondary outcome [13] 318927 0
Waist circumference
Timepoint [13] 318927 0
Baseline, post-treatment and 1 year follow-up post-treatment.
Secondary outcome [14] 318930 0
COMPOSITE OUTCOME: Body composition assessment: We will use a portable bioelectrical impedance scale (from Tanita) to calculate an estimate of total body water, which can then be used to estimate fat-free body mass and, by difference with body weight, body fat.
Timepoint [14] 318930 0
Baseline, post-treatment and 1 year follow-up post-treatment.

Eligibility
Key inclusion criteria
Participants must be aged between 18 and 55 and have a BMI of 30 or above.

Minimum age
18 Years
Maximum age
55 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Serious somatic conditions (e.g., neurological disorders, stroke, head injury); serious psychiatric/psychosomatic conditions (e.g., psychotic disorder, suicidality, substance use disorder, attention deficit hyperactivity disorder, developmental or intellectual disability; impediment in hearing, vision, or language with an effect on testing; previous or planned bariatric surgery; use of medication that impacts weight or executive functioning (e.g., antipsychotics, sedatives, hypnotics); and ongoing psychotherapy.

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Participants will be randomly allocated to a treatment condition following a blind randomisation procedure, reported according to CONSORT. The treatment condition for each individual will be predetermined by the use of an external web-based randomisation program, called Sealed Envelope (www.sealedenvelope.com), which can only be accessed by an investigator not responsible for recruitment or assessment.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Randomisation will be stratified by sex, age and weight.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s

The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Other design features
Phase
Not Applicable
Type of endpoint/s
Statistical methods / analysis
Data will be inspected for normality and non-parametric statistic applied where appropriate. Weight loss percentage will be computed. Scores on cognitive measures will be transformed into z-scores. Linear mixed models will be used to compare differences between treatment groups in % weight lost, and to examine whether changes in executive function predicted changes in weight. To examine the baseline and prospective relationships between biological data and cognition/weight. linear or logistic regression analyses will be performed while controlling for a range of potential confounders. The Bonferroni correction or FDR (False Discovery Rate) method will be used for multiple comparisons and post-hoc testing will be performed where appropriate.

Power Calculations: We calculated the sample size with a method that takes into account
the intracluster correlation coefficient (r=.02) for comparison between groups using a two-tailed linear mixed model, predicting a medium effect size (Cohen's d of .4 – which is the difference between the effect size of CRT(1.2) and brief BWL (.8) compared to waitlist control on weight loss and using a power of 80%, and determined that a sample size of 70 individuals per group is needed. Assuming an attrition rate of 25%, a sample of 88 per group is necessary, totalling 176 participants (14 groups of 12 people on group BWL).

This sample will also allow the detection of small effect sizes (Cohen’s f-squared = 0.01) for
a given predictor in the presence of 10 other predictor variables in the regression equation, based on a two-tailed alpha rate of .05 and power of .80. Stratification by SES, age or sex, to explore the findings in more detail, is also possible and the sample size should suffice.

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
NSW

Funding & Sponsors
Funding source category [1] 292329 0
Charities/Societies/Foundations
Name [1] 292329 0
Clive and Vera Ramaciotti Foundation
Country [1] 292329 0
Australia
Funding source category [2] 292330 0
University
Name [2] 292330 0
WESTERN SYDNEY UNIVERSITY
Country [2] 292330 0
Australia
Primary sponsor type
Individual
Name
Dr Evelyn Smith
Address
School of Social Sciences and Psychology
Western Sydney University
Locked Bag 1797
Penrith NSW 2751
Country
Australia
Secondary sponsor category [1] 291007 0
Individual
Name [1] 291007 0
Charlotte Whittingham
Address [1] 291007 0
School of Social Sciences and Psychology
Western Sydney University
Locked Bag 1797
Penrith NSW 2751
Country [1] 291007 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 293795 0
Human Ethics: Western Sydney University
Ethics committee address [1] 293795 0
Bankstown Campus
Bullecourt Avenue
Milperra
NSW 2214
Ethics committee country [1] 293795 0
Australia
Date submitted for ethics approval [1] 293795 0
20/01/2016
Approval date [1] 293795 0
06/04/2016
Ethics approval number [1] 293795 0
H11475

Summary
Brief summary
Obesity is at epidemic proportions and current weight loss programs offer little
respite. While many current interventions help individuals to reduce 5-10% of their body weight, most individuals regain the weight as soon as professional contact ends (Perri & Corsica, 2002). Treatment strategies that will aid with weight loss maintenance are urgently needed.

Recently weight loss failure has been linked to cognitive difficulties, specifically problems with executive functioning. Executive functioning encompasses a range of processes that facilitate initiation, inhibition, planning, regulation, sequencing and achievement of complex goal-oriented behaviour. It is evident that executive functioning underlies many behaviours associated with successful weight management (Riggs, Spruitt-Metz, Chou & Pentz, 2012). Our review (Smith et al., 2011) found 22 out of 24 studies showed a negative association between obesity and executive function. Despite this, current treatments do not target executive function deficits.

Manualised cognitive remediation therapy (CRT) is a face-to-face treatment approach with a focus on improving cognitive functioning. CRT consists of mental exercises aimed at improving cognitive strategies, thinking skills and information processing through practice (Tchanturia, 2014).

There is evidence that CRT improves executive function and helps individuals regulate their eating. It has been shown to be effective at improving executive function in those with anorexia nervosa (Dingemans et al., 2014). Our recent pilot RCT on manualised CRT for obesity provides promising evidence for its efficacy (Raman, Hay & Smith, 2014). The results showed that those in the CRT group experienced a significant increase in executive function and a significant decrease in weight compared to controls and that changes in executive function predicted changes in weight.

This study aims to determine the efficacy of CRT in reducing weight and improving executive function in obese patients. The following conditions will be compared; CRT plus behavioural weight loss (BWL) compared to BWL (standard care) alone. It is hypothesized that individuals who receive CRT will show greater weight-loss and improved executive functioning than those in the BWL alone, both at post-treatment and at 1-year follow-up (post-treatment).

Treatment will continue for 5 months and be provided by two psychologists and a dietician. Participants aged 18 to 55, with a BMI of 30 or above will be randomly allocated to one of two conditions:
1) CRT group: Eight 50 minute weekly sessions of individual CRT plus twelve, 2hour, weekly sessions of group Behavioural Weight Loss (BWL)
2) BWL group: Eight 50 minute weekly sessions of individual BWL plus twelve, 2 hour, weekly sessions of group Behavioural Weight Loss (BWL)

Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 60954 0
Dr Evelyn Smith
Address 60954 0
School of Social Sciences and Psychology
Western Sydney University
Locked Bag 1797
Penrith NSW 2751
Country 60954 0
Australia
Phone 60954 0
+61 2 9772 6491
Fax 60954 0
Email 60954 0
Contact person for public queries
Name 60955 0
Ms Charlotte Whittingham
Address 60955 0
Project Officer - CRTO Project
School of Social Sciences and Psychology
Western Sydney University
Locked Bag 1797
Penrith NSW 2751
Country 60955 0
Australia
Phone 60955 0
+61 2 9772 6491
Fax 60955 0
Email 60955 0
Contact person for scientific queries
Name 60956 0
Dr Evelyn Smith
Address 60956 0
School of Social Sciences and Psychology
Western Sydney University
Locked Bag 1797
Penrith NSW 2751
Country 60956 0
Australia
Phone 60956 0
+61 2 9772 6491
Fax 60956 0
Email 60956 0

No information has been provided regarding IPD availability


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No Supporting Document Provided



Results publications and other study-related documents

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