Kg-Free: an Acceptance, Mindfulness and Compassionate-based Intervention for Women Struggling With Their Weight
Condition: Overweight and Obesity
MeSH terms: Overweight
Study type: Interventional

Summary: 
      This study aims to test the efficacy and feasibility of an acceptance, mindfulness and
      compassionate-based intervention for women with overweight and obesity without binge-eating
      disorder (Kg-Free). Kg-Free intervention comprises 10 weekly group sessions plus 2 booster
      fortnightly sessions (31/2months) 2h30 hours each, run in small groups at Coimbra's
      University Hospital. The main goal of Kg-Free intervention is to reduce weight self-stigma
      and unhealthy eating behaviours and promote quality-of-life by targeting weight-related
      experiential avoidance and self-criticism patterns. The intervention focuses on fostering a
      greater awareness and ability to be in contact, tolerate and accept all internal experiences
      (even the unwanted ones, such as craving for food, fatigue, stigma and shame), rather than
      trying to avoid, control or change them. Additionally, the intervention intents for
      participant's to develop a compassionate attitude towards themselves, especially during
      challenging times in order to decrease shame and self-criticism.
    

Detailed description: 
      This project aims to develop and test the efficacy of an integrated intervention (Kg-FREE),
      based on different and complementary approaches from the 3rd generation therapies (Acceptance
      and commitment therapies - ACT, Mindfulness and Compassion Focused Therapy) that have been
      showing promising results individually, but that were never tested simultaneously in
      intervention for people struggling with their eating and weight. Moreover, the intervention
      aims to act specifically on patients' self-criticism and experiential avoidance patterns in
      order to reduce weight-self-stigma and promote healthy behaviours and quality-of-life.
      Indeed, several studies have been suggesting the crucial role of these emotional regulation
      processes on behavioural modification. This study will investigate the impact of the changes
      in several psychological processes in different obesity dimensions, such as body mass and
      biochemical parameters associated with health risks, eating behaviours, stigma, health and
      quality of life.

      The Kg-FREE intervention encloses 10 weekly group sessions (2, 5 hours/ each), highly
      experiential followed by two 2 booster fortnightly sessions. The intervention is divided into
      several modules, that are applied in a structured way: a) psycho education related to eating
      and physical exercise healthy habits; b) how our brain works and how does this relate to our
      eating and weight; c) Life values identifications to enhance intrinsic motivation; d)
      cognitive fusion and experiential avoidance as maladaptive strategies that underlie the
      psychological suffering, the negative affect (e.g. shame) and self-criticism; e) mindfulness
      exercises as a more adaptive strategy for emotional regulation; f) development of
      self-compassion as an antidote for shame and self-criticism, activating the soothing system
      and deactivating the threat system.

      Kg-Free sessions were carried out by a clinical psychologist with previous training in
      contextual-behavioral therapies and one clinical psychology master student. The intervention
      protocol was built upon pre-existent ACT and mindfulness-based protocols for people with
      eating and weight issues (e.g., Forman et al., 2013; Kristeller & Wolever, 2011; Lillis et
      al., 2009; Tapper et al., 2009). Additionally, and because it has been recognized the
      importance of integrating compassion in behavioural interventions (e.g., Luoma & Platt,
      2015), specially to deal with shame and self-criticism (Gilbert, 2010) a compassion component
      was added. This component aimed at training participants to develop a more accepting and kind
      relationship with themselves, particularly when things go wrong or when facing errors or
      failures.

      All session followed the same basic structure, starting with 30 minutes of shared experience,
      followed by a five-minute mindfulness practice. Then the session content was delivered,
      followed by an eating mindfulness practice to train the ability to pay attention to food and
      eating physical sensations. Finally, the session content was briefly revised and practices
      for the week were established (e.g., mindfulness or compassion exercises). A participants'
      manual was provided, which included the targeted constructs, examples and exercise sheets.
      Audio files were given to the participants to ensure the practice of mindfulness and
      compassion exercises between sessions. Moreover, a Portuguese therapist manual was also
      assembled and is available upon request.

      Previously to data collection, ethical approval was obtained from Clinical Trials Unit from
      Coimbra's University Hospital. Participants were adult women, aged between 18 and 55 years
      old, with overweight or obesity (BMI ≥ 25) without binge-eating, enrolled in nutritional
      treatment for weight loss in primary care units and Hospitals from Coimbra's district,
      Portugal. Participants were recruited directly at the medical care units in the day of their
      appointment. Participants were informed about the voluntary and confidential nature of the
      data. Also, a brief overview of the treatment program was presented and participants were
      required to sign the informed consent. In order to assure confidentiality a numerical unique
      code was assigned to each participant.

      After eligibility assessment, participants that meet inclusion criteria were randomly
      assigned into one of the two study conditions - experimental group that will receive the
      Kg-Free intervention and a control group that will maintain Treatment as usual (which
      consisted in dietary and physical activity support), using a using a computer-based random
      allocation. The study followed the principle of treatment received.

      The study comprised four different assessment moments (M0, M1, M2 e M3), namely before
      intervention (M0), at the end of the intervention (M1) and two follow-up moments at three
      (M2) and six months (M3) after the intervention. In all assessments data regarding
      participants' biochemical (lipid profile) and body mass parameters, eating behaviours,
      health, stigma and quality of life as well as psychological processes was collected.
      Regarding biochemical data, the blood samples were collected and analysed by the clinical
      analysis laboratory from the Pharmacy department. Confidentiality was assured hence only the
      research code for each participant was provided to the laboratory. All participants were
      weighted with their street clothes (without shoes) using the same Body Composition Analyzer
      (Tanita TBF-300) accurate to 0.1kg. Waist circumference was measured using a tape measure at
      the umbilicus. The remaining data collection was carried out by clinical psychologists from
      the research team (blinded to participant's treatment condition).

      Statistical analysis All data analyses were performed using Statistical Package for the
      Social Sciences (SPSS, V.20) and alpha level was set at .05. Independent sample t tests were
      used in order to compare intervention and control groups at baseline. Power analysis for
      ANCOVA was calculated at priori. Using a significance level of p<.05 and a power of 80%, a
      sample size of 31 per group (N = 62) was needed to detect a standardized effect size of f =
      0.40.

      To test between-group differences at post-treatment ANCOVA with baseline as covariate and
      condition as a fixed factor were performed. Paired samples t-tests were performed to explore
      within-group differences from pre to post test, for each group separately. All effect sizes
      were calculated using Cohen's d.

      In a second study, Repeated Measures ANOVA was performed to test differences between
      pre-treatment, post- treatment and 3month follow-up assessments for all participant's that
      completed Kg-Free intervention (N = 53). Whenever sphericity assumption was violated, the
      Greenhouse-Geisser correction was used to produce a valid F-ratio. Post-Hoc analyses using
      Bonferroni adjustment for multiple comparisons was used to explore pairwise differences
      (pre-to-post treatment; pre-to-3 months and post-to-3 months). Effect sizes were calculated
      using partial eta square (ƞ2). Finally, to explore the psychological processes that underlie
      the changes in health and weight and eating-related outcomes after the Kg-Free intervention
      MEMORE macro (Mediation and Moderation analysis for Repeated measures designs) was used.
      MEMORE allows for the estimation of total, direct, and indirect effects of independent
      variable (X) on dependent variable (Y) through one or more mediators (M) simultaneously
      two-occasion within-subjects design.
    

Intervention name(s): Kg-Free; Treatment as Usual
Intervention type(s): Behavioral; Other
Intervention description(s): Cognitive-behavioral intervention based on promoting acceptance, mindfulness and self-compassion abilities; Standard nutritional treatment that involves dietary and physical activity support provided by the medical units Standard
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Outcomes Assessor)
Primary purpose: Supportive Care
Keywords: Mindfulness; self-compassion; Acceptance and Commitment Therapy; weight self-stigma; quality-of-life