Personalisation of anti-obesity medication selection using the novel Auckland Eating Behaviour Questionnaire to identify Eating Behaviour Traits: examining the impact on weight loss

We propose that identifying predominant eating behaviour phenotypes, will improve pharmacotherapy selection to maximise weight loss and improvement in obesity related complications. We recently successfully validated in a large cohort (729 participants) the Auckland Eating Behaviour Questionnaire (A-EBQ), which identified three distinct clusters of eating behaviour traits that have been described in the literature. These are type C – constant cravers with reduced satiety and uncontrolled hunger leading to disinhibited eating and likely to respond best to phentermine, type E – emotional eaters, which comprises several forms of emotional eating, including food reward, eating when anxious, sad, or using food as a substitute and type F – feasters with weak post-ingestive satiation response resulting in overeating at mealtimes.' 'Eating behaviour congruent treatment group means that we will match the medication to the participants dominant eating behaviour trait, eating behaviour incongruent group means that participants will be treated with a medication that does not match their dominant eating behaviour. All participants will be equally randomised to either a congruent or incongruent treatment at the time of enrolment. The groups will be as follows: Eating behaviour congruent treatment group E: 25 participants with emotional eating assigned to Naltrexone/Bupropion 8/90mg 2 tablets twice daily Eating behaviour congruent treatment group C: 25 participants with uncontrolled hunger assigned to Duromine 15mg tablets once daily Eating behaviour congruent treatment group F: 25 participants with weak satiation response assigned to Liraglutide (1.8-3mg subcutaneous injection once daily) Eating behaviour incongruent treatment group IE: 25 participants with emotional eating randomised to either Duromine 15mg tablets once daily or Liraglutide (1.8-3mg subcutaneous injection once daily) Eating behaviour incongruent treatment group IC: 25 participants with uncontrolled hunger randomised to either Naltrexone/Bupropion 8/90mg 2 tablets twice daily Eating behaviour incongruent group IF: 25 participants with weak satiation response randomised to either Naltrexone/Bupropion 8/90mg 2 tablets twice daily Control group: A ‘lifestyle only’ control group will have the lifestyle interventions described below to be able to compare the medication effect vs. the lifestyle and the effect of being enrolled in a clinical trial. This group will have a random selection of eating behaviour traits. There will be no placebo as the different treatments consist of different treatment modalities (two oral tablets twice daily, one oral capsule once daily, and a subcutaneous injections once daily) and randomisation is based on eating behaviour trait. The results of the eating behaviour assessment will be blinded to the investigator and the participants. Mode of administration: Duromine oral capsules will be administered by the participant once daily. Adherence will be measured by tablet return (pill count) at the time of re-prescription (3 monthly). There is no requirement for medication titration. The active intervention period on stable treatment dose is for the duration of six month. The medication will not be changed during this time, except the participant experiences problems or side effects. Naltrexone/Bupropion 8/90mg oral tablets will be administered by the participant two tablets twice daily. Adherence will be measured by tablet return (pill count) at the time of re-prescription (3 monthly). The medication will be titrated to the target dose or the maximum tolerated dose with incremental steps of one additional tablet per week. The titration period will last up to one month. This time is part of the active intervention period of six month. Participants will be on stable treatment dose for the duration of the trial, except the participant experiences problems or side effects. Liraglutide subcutaneous injections will be self-administered by the participant once daily. All participants will have a training session in self-injection techniques by the investigator before commencement of treatment. The medication will be titrated to the target dose of 3.0mg or the maximum tolerated dose in incremental steps of 0.6mg increase per week. This time is part of the active intervention period of six month. Participants will be on stable treatment dose for the duration of the trial, except the participant experiences problems or side effects. Adherence will be measured by injection pen inspection (pen return) at the time of re-prescription (3 monthly). All participants will also receive a 'lifestyle' intervention. The registered dietitian will conduct two 60-90 min group meetings to provide basic nutrition guidelines on healthy food choices for improved glycaemic control as per the New Zealand Standards of Care for the Nutritional Management of Type 2 Diabetes in Adults Guidelines. The first session will be at the start of the trial (prior to starting the medication); the second session will be within four weeks after the first session. The first baseline group meeting will cover basic healthy eating and instructions for the ‘mealtime’ tool. The second group meeting, 4 weeks after the first session would provide diet counselling around basic healthy eating and cognitive behavioural therapy on implementing these healthy eating changes over the rest of the study period. There will be no other associated interventions and there will be no diet adherence monitoring during the trial, but a semi-structured interview will be conducted after three and six months, evaluating significant diet adherence concerns. All participants will have free access to a diet and meal planning tool ‘mealtime’ (http://meatime.com). The instructions to the use of the meal planning ‘mealtime’ tool will be provided at the group meetings, encouraging participants to use the app at least once a week (allocate one hour planning time) to plan weekly meals a week in advance. The researchers will have the opportunity to access app analytics at the end of the trial. There will be no stipulation for change in the level of exercise during the trial.