Protocol for: The Use of Intra-Gastric Balloons as an Adjunct to a Lifestyle Support Programme to Promote Weight Loss in Severely Obese Adolescents

¹Sheffield Hallam University, HWB, Collegiate Hall, Centre for Sport and Exercise Science, Sheffield Hallam University, Sheffield, S10 2BP, UK

²Endocrinology Department, Sheffield Children’s Hospital, UK

³Gastroenterology Department, Sheffield Children’s Hospital, UK

*Corresponding Author:

Reece LJ
Sheffield Hallam University
HWB, Collegiate Hall
Centre for Sport and Exercise Science
Sheffield Hallam University, Sheffield
S10 2BP, UK
Tel: +441142254355
E-mail: l.reece@shu.ac.uk

Received Date: October 21, 2013; Accepted Date: November 11, 2014; Published Date: November 14, 2014

Citation: Reece LJ, Copeland RJ, Sachdev P, Thomson M, Wales JK et al. (2014) Protocol for: The Use of Intra-Gastric Balloons as an Adjunct to a Lifestyle Support Programme to Promote Weight Loss in Severely Obese Adolescents. J Child Adolesc Behav 2:173 doi:10.4172/2375-4494.1000173

Copyright: © 2014 Reece LJ, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

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Abstract

Background: Severe childhood and adolescent obesity (BMI>3.5SD) remains a significant public health priority with an increasing incidence and is associated with significant morbidity including immediate and long-term cardiovascular, metabolic and psychological consequences. Current non-invasive treatments including lifestyle modification and pharmaceutical intervention are of limited effectiveness in this population, which leaves permanent bariatric surgery as the only viable option. As an alternative, intra-gastric balloons offer a reversible, potentially safer and less invasive option for severely obese adolescents for whom all other available treatments have been exhausted. Methods/design: BOB is a non-randomised pilot study. A cohort of 12 obese adolescents (BMI > 3.5SD, puberty stage 4 or more) aged 13 - 16 years, will be recruited to the study, where an intragastric balloon (ORBERA – inflated to 500-700ml) will be inserted into the stomach for 6 months, whilst receiving intense, weekly, behavioural support for the family. Follow-up will continue for 18 months after balloon removal with reduced behavioural support. The primary outcome measure will be the change in body weight and BMI standard deviation score from baseline following six months with the intragastric balloon and lifestyle therapy. Secondary outcome measures include the assessment of weight maintenance at 18 months post balloon removal, biomedical outcomes including blood glucose levels, physical activity and physical fitness, and psychosocial outcomes such as paediatric health-related quality of life.

Keywords

Childhood; Weight; Lifestyle; Pharmaceutical

Abbreviations

BOB - Balloons in obesity; LR - Lindsey Reece (lead author); RC - Robert Copeland; NW - Neil Wright; PS – Pooja Sachdev; LDA – Lizzy De Angelis; BMI - Body Mass Index; WHO - World Health organisation; NICE - National Institute for Clinical Excellence; BIB - Bioenterics fluid filled balloons; Peds QL - Paediatric quality of life; TPB -Theory of planned behaviour; HOMA - Homeostasis model assessment; HR PQCT - High resolution peripheral quantitative computed tomography; HDL - High density lipoprotein; LDL - Low density lipoprotein; GLP-1 - Glucagon-like peptide-1GIP - Gastric inhibitory polypeptide; DXA - Dual-energy X-ray absorptiometry; CYPSPP - Child and Youth Self-perception profile; OGTT - Oral glucose tolerance test; U&E -Urea and Electrolytes; LFT’s - Liver function test; PAQ - Physical activity questionnaire for adolescents

Background

The prevalence of overweight and obesity in children and adolescents continues to rise, presenting a major challenge for health-care providers. Globally, the number of overweight and obese individuals increased from 857 million in 1980, to 2.1 billion in 2013 [1]. Prevalence has increased substantially in children and adolescents in developed countries, with 23.8% (22·9–24.7) of boys and 22.6% (21.7–23.6) of girls overweight or obese in 2013 [1]. In developing countries, obesity also increased from 8.1% (7.7–8.6) to 12.9% (12.3– 13.5) in 2013 for boys, and from 8.4% (8.1–8.8) to 13.4% (13.0–13.9) in girls [1,2]. Here in the United Kingdom, UK, obesity rose amongst 2-10 years old to 13% in 2010-2012, with 18.7% of older children aged 11-15year obese and 35% overweight and obese [3]. Consequences of severe obesity at an early age include; orthopaedic complications, type 2 diabetes, increased risk of cardiovascular disease and hypertension [4]. Worryingly, the majority of these medical concerns have traditionally only presented in adults [2,4] and as Reilly and Kelly (2011) reviewed, a large body of evidence now confirms obesity in childhood and adolescence can lead to premature mortality and physical morbidity in later life [2]. The psychopathology of obesity in young people is a concern with overweight and obese children experiencing poor quality of life, lower self-esteem [5,6] and an enhanced risk of being socially isolated than their healthy weight counterparts [7]. Several variables are associated with low Quality of life, QOL, such as self-image, bullying, bodily pain, quality of food intake, physical activity, screen time, parents, and weight status [6]. Being obese in childhood is also associated with depressive symptoms and thoughts of suicide, often linked to bullying in schools and/or through the use of social media networks [8,9]. Taken collectively these data confirm the dire need to intervene with efficient and cost-effective treatment programmes for young people who are severely obese.

The National Institute for Health and Clinical Excellence (NICE) presents treatment guidelines for overweight and obese children and young people, emphasizing the importance of lifestyle interventions focusing on diet control, physical activity and behavioural change all being delivered within a multi-disciplinary framework [10,11]. Yet, for many adolescents whose Body Mass Index (BMI) place them in the severely obese bracket (i.e. BMI >99th percentile), lifestyle interventions are ineffective with only modest short-term efficacy in terms of weight-related outcomes [2]. Perhaps due to the added complexity of being severely obese, treatment programmes for this population often report high attrition rates, usually failing to ensure significant and sustained weight loss longer-term [12]. As adults (equivalent BMI >40, or >35 with co-morbidities), these individuals would be considered for bariatric surgery [10], which is associated with long-term successful weight loss [13]. In response to rising obesity prevalence, there is a growing body of research exploring the use of bariatric surgery in young people. A review of bariatric procedures [13], including the adjustable gastric band, sleeve gastrectomey, roux-en-Y gastric bypass and biliopancreatic diversions, in obese children and adolescents indicate significant decreases in BMI one year post-surgery with some evidence of co-morbidity resolution and improvements in health-related quality of life [13,14] reported results from a prospective study of 81 adolescents undergoing laparoscopic Roux-en-Y gastric bypass and showed a 32% reduction in BMI after 2 years [15]. Despite growing evidence from the research community, for the use of bariatric surgery as a safe and effective treatment option for severely obese adolescents [13,15], inconsistencies with protocol reporting, lack of detail on surgical complications [16] and limited reports of the long-term effectiveness [13], results in some practitioners and policy-makers hesitant to recommend surgery as a treatment [17-19]. This reluctance to perform bariatric surgery more frequently in adolescents is reinforced by, current UK clinical guidelines that specify adolescent bariatric surgery should only be considered in exceptional individual circumstances [9]. Yet there is strong recognition that novel, less invasive, whilst equally effective treatment strategies tailored to the needs of severely obese adolescents [20,21] are warranted. One such approach, which is proposed here, is the use of intra gastric balloons as a potential, reversible, intervention for adolescent obesity.

Intragastric balloons were first proposed as an aid for weight loss more than 20 years ago [22]. Since then, Bioenterics fluid-filled balloons (BIB) have been sited endoscopically into the stomach typically for six months, to induce satiety by reducing the stomach capacity, thereby reducing food intake and encouraging weight loss amongst obese populations [23,24]. A systematic review by Dumonceau (2008) of BIB treatments reported a mean weight loss of 17.8 kg, ranging from 4.9 kg – 28.5 kg [21]. Imaz (2008) reported a weight loss of 14.7 kg at 6 months representing a 32.1% loss of excess weight and a BMI change of 5.7 [22]. Building on the learning from weight management literature, treatment with BIB should be proposed in the setting of a multidisciplinary framework [22] to help promote and sustain the lifestyle changes adopted [10]. Studies assessing lifestyle modification, quality of life and psychosocial impact are limited, with little data on long-term follow-up post balloon removal [22]. In addition to weight loss, psychopathologic outcomes must be assessed as participation in supervised exercise therapy interventions have been shown to improve measures of self-esteem and increased physical activity among obese children [25-28].

This pilot study proposes the use of intragastric balloons, alongside a lifestyle support programme, to help severely obese adolescents to lose weight. The study is entitled Balloons in Obesity given the acronym BOB.

Methods / Design

Study aims

The primary aim of BOB is to assess the feasibility of using an intrasgastric balloon, alongside a lifestyle support programme, to promote weight loss in severely obese adolescents at six months. Weight maintenance will be assessed 18 months post-balloon removal.

Study design and setting

BOB is a non-randomised pilot study. This involves 12 obese adolescents (BMI > 3.5SD, puberty stage 4 or more) aged 13 - 16 years, recruited to the study, where an intragastric balloon (ORBERA – inflated to 500-700ml) will be placed in-situ endoscopically under general anaesthesia at a specialised children’s hospital, for 6 months, whilst receiving intense behavioural, lifestyle support for the family. Follow-up will continue for 18 months after balloon removal with reduced behavioural support. This study incorporates medical evaluation and monitoring led by a paediatrician alongside receiving nutritional advice, physical activity counselling and behavioural support, delivered by a Research Fellow at an English university, aimed to optimise the likelihood of patients achieving desired outcomes.

Participant eligibility

Participants will be recruited according to the following inclusion criteria: (1) Clinically Obese and aged 13 - 16 years old (BMI > 3.5 SD); (2) have attained or nearly attained adult stature and stage 4 pubertal development; (3) Have previously attempted weight loss through a structured management programme (4) Are able to attend weekly sessions with researchers and are capable of adhering to the lifestyle changes advised. Exclusion criteria are as follows: (1) previous oesophageal or gastric surgery or history of intestinal obstruction; (2) history of inflammatory disease of the gastrointestinal tract such as oesophagitis, gastric or duodenal ulcers or congenital anomalies such as atresias or stenosis; (3) Hiatus hernia >5 cm (assessed at balloon insertion); (4) History of, or current significant psychological disorder (permission sought from lead care giver).

Ethical considerations

Significant public and patient involvement was sought during project development. Full ethical approval for this study has been obtained from the NHS Sheffield research ethics committee. Written informed consent will be required from all participants and their parents prior to commencing the study.

Study interventions

An intragastric balloon (ORBERA TM– inflated to 500-700ml) will be placed in-situ endoscopically under general anaesthesia. The balloon will remain in place for 6 months with monthly assessments by the research paediatrician and gastroenterologist to ensure correct balloon placement and provide routine medical check. To reinforce lifestyle changes, families will attend weekly sessions lasting for up to an hour, at a time that suits the family, with the research fellow at the university facility. Upon request, up to 6 sessions could be held in families’ local community to encourage sustained lifestyle change. In line with NICE (2011) guidance and previously reported evidencebased obesity intervention [25,28], the multi component intervention will include behaviour change strategies to increase families’ physical activity, improve eating behaviour, and provide social support as well as supervised exercise sessions. Sessions will be client-centred and tailored to the needs of the young person and their family. Follow-up sessions with the research paediatrician and research fellow will take place up to 18 months after balloon removal.

Intervention schedule

The BOB programme will be delivered, in total, over two years by a multi-disciplinary team (Paediatrician’s (NW & PS); Dietician (LDA); Chartered Psychologist (RC); Research Fellow (LR); Research Nurses. The medical component of the study is overseen by Consultant Paediatrician NW, delivered by Paediatrician PS, with the behaviouralprogramme overseen by Chartered Psychologist (RC) and delivered by Research Fellow (LR) specialising in delivering behaviour change programmes with obese populations. Once recruited, families begin with a four week preparatory phase prior to balloon insertion, then undergo six month intensive lifestyle support, and a two month relapse prevention phase post-balloon removal. Follow-ups with both the paediatrician and research fellow take place at 6, 12 and 18 months post-balloon removal.

Preparatory phase (0-4 weeks)

Once recruited, all families commence the study by undergoing weekly sessions for four weeks, aimed to ensure families are certain of their decision to participate, are fully aware of the implications of their decision, understand what is involved and are committed to the project. This time frame provides the opportunity for the research team to assess patient suitability, conduct the baseline assessments and continue to build rapport.

Early weeks of BOB (4-8 weeks)

This first month living with the balloon provides opportunity to build rapport between the research team, the adolescents and their families. The focus of the behaviouralprogramme is to explore participant expectations from the study,with individual success criteria and discussion of goals all informing tailored support and an agreed action plan for the delivery of the programme. From a medical perspective, the focus is on participant safety ensuring balloon placement is correct and offering weekly medical check-ups with associated appropriate tests.

Living with BOB (9–20 weeks) and Post BOB (20-28 weeks)

The remaining 5 months with the balloon inserted, and for 2 months after balloon removal, participants will follow a weekly lifestyle support programme delivered by the research fellow (LR). Individual sessions will last approximately 1 hour and include a mix of physical activity, support for behaviour change and nutrition advice (e.g. understanding food labels, portion control and healthful eating). The lifestyle programme will be underpinned by recognised models of health-related behaviour change [26,27] and adhere to previously efficacious approaches with overweight and obese young people [29,30]. To achieve a person-centred approach, sessions will be delivered in accordance within the spirit of Motivational Interviewing, MI [28]. Furthermore, the lifestyle programme will utilise a variety of commonly applied behaviour change techniques [30,31] to enhance physical activity and diet-related behaviour. Due to the lack of detail and consistent reporting of behaviour change techniques utilised in physical activity and health behaviour change programmes, Abraham and Mitchie developed the taxonomy of behaviour change techniques, to standardise and hopefully resolve this issue [29,30]. To standardise the techniques utilised in this study, table 1.0, attempts to map techniques with definitions and techniques provided by Abraham and Mitchie, with the addition of examples highlighting where they will be delivered throughout BOB.

Table 1: Mapping of behaviour change definitions and techniques to the BOB protocol

During sessions participants and their families and friends will also be offered a range of aerobic exercise modalities including gymbased equipment (e.g. treadmills and bikes), outdoor activities such as walking, as well as the use of exercise DVD’s. The exercise sessions will be delivered in small bouts of no more than 10-minutes to build self-efficacy and will be of moderate intensity, in line with Public Health England recommendations [31-33]. Sessions will also include mini-games and self-referenced competitions to help motivate and build self-worth. These approaches have been shown to help build global self-worth and promote adherence to the intervention [25]. During the sessions the rating of perceived exertion will be measured using the pictorial children’s effort rating table (PCERT) [32]. Participants will be asked to point to how they feel the exertion compares against a 10 point scale. Medical assessments take place once a month with PS at the children’s hospital. 4.9 Dietetic Input All participants and families will receive two, one-hour sessions with a specialist dietician (LDA). One session before the balloon is inserted to support participants from a full fluid diet through to the re-introduction of solid foods, and once after the balloon is removed to reinforce the maintenance of reduced calories and portion size and commitment to a healthy balanced diet. Under specialist circumstances participants can access dietetic support throughout the programme; however key healthy eating messages will underpin the weekly delivery of the lifestyle support programme as previously mentioned.

Outcome measures

The primary outcome measure is the change in body weight and BMI standard deviation score from baseline following six months intragastric balloon therapy and lifestyle programme. Secondary outcome measures include the assessment weight maintenance at 18 months post balloon removal, biomedical outcomes including blood glucose levels, and psychosocial outcomes such as paediatric healthrelated quality of life.

Biomedical outcomes

Biomedical outcomes comparing change in biomedical data at the various time points (baseline, following six months intragastric balloon therapy and subsequently at 18 months post balloon removal) include:

• Difference in fasting glucose, fasting insulin glucose ratio and HOMA

• Difference in total cholesterol, HDL, LDL, triglycerides and atherogenic index.

• Difference in systolic and diastolic blood pressure standard deviation scores.

• Change in liver function tests

• Changes in Ghrelin, GLP-1 and GIP levels

• Changes in adipokines, osteokines, bone formation and turnover markers

Changes in total fat mass, bone mineral content and bone density as assessed by DXA and changes in bone architecture as assessed by highresolution peripheral quantitative computed tomography, HR pQCT.

Psychosocial Outcomes

Paediatricquality of life

The PedsQL Measurement Model is a modular approach to measuring health-related quality of life (HRQOL) in children and adolescents including 1) Physical Functioning (8 items), 2) Emotional Functioning (5 items), 3) Social Functioning (5 items), and 4) School Functioning (5 items). The PedsQL consists of brief, practical, generic core scales suitable for use with healthy school and community populations, as well as with paediatric populations with acute and chronic health conditions [34]. In a study looking at health- related Quality of Life, overweight and obese adolescents reported significantly lower scores compared to their healthy counterparts [35].

Physical self-perceptions

Self-perception is to be measured on the subscale from the Children and Youth Physical Self-perception Profile (CY-PSPP) developed in 1989 and adapted for use in children in 1995 [36]. The CY-PSPP contains 6 subscales; Sport/Athletic, Attractive Body Adequacy, Condition, and Strength competence as well as Physical and Global Self-Worth. The Children and Youth Physical Self-Perception Profile (CY-PSPP) assesses the degree to which young people view themselves as competent in a variety of physical domains [37,38]. Each question contains two statements relating to either a positive perception of competence or a negative perception of competence. The respondent is required to choose which statement best describes the way they view themselves and answer either ‘sort of true for me’ or ‘really true for me’ for each statement. Questions are structured in an alternative format on a scale between 1 (low score) and 4 (high score). Affect [39].

Participants are asked to indicate the degree, using a scale of 1 (very slightly) to 5 (extremely), each adjective describes how they have felt the previous week. Positive items include proud, satisfied, happy, excited and relaxed and the negative effect includes unhappy, nervous, guilty and angry. Assessment of planned behaviour The Theory of Planned Behaviour (TPB) was developed to predict behaviours in which individuals have incomplete volitional control [27]. In light of the fact that the lifestyle intervention study holds a focus on improving physical self-competence and self-efficacy towards exercise and given that perception of behavioural control as indicated by TPB can reflect past experiences, anticipation of upcoming circumstances, and the attitudes of the influential norms that surround the individual, components from the TPB will be assessed [39]. Participants will be asked to indicate by circling a number between one (strongly agree) and 7 (strongly disagree) to what extent they agree with statements such as; “I would like to participate in physical activity at least three times per week”, “If I wanted to, I could easily take part in regular physical exercise” or “Most people who are important to me, think I should take part in regular physical exercise”.

Physical fitness

Physical fitness will be measured using the modified Balke protocol [40]. The modified Balke protocol requires participants to walk at a pace of 1.34 m s-1 at a grade of 6% for 2 minutes. At the end of the two-minute stage, the grade is increased by 2%. This continues until volitional exhaustion. On the occasions that the treadmill reaches maximal elevation the participant continues to walk at that gradient until volitional exhaustion. The speed of the treadmill remains constant at 1.34 m s-1 for the duration of the protocol. The protocol ends at volitional exhaustion with time to exhaustion recorded. The test is continuous with no rest periods between each stage. Heart-rate (HR) will be measured during the last minute of each stage using a shortrange radio-telemetry monitor.

Physical activity level

The Physical Activity Questionnaire for Adolescents [40] will collect specific information about participation in various physical activities during the previous week. Specifically, participants are questioned about their engagement in (1) physical activities in their spare time; (2) physical education (3) lunchtime physical activities (4) extracurricular activities, (5) evening physical activities and (6) weekend activities. Each physical activity is scored on a scale between 1 (not engaged) to 5 (involved 5-7 times per week).

Assessment of outcomes

All outcomes will be measured at baseline, within 2 weeks of balloon insertion, and within 2 weeks of balloon removal after 6 months, then a further 6, 12 and 18 months post balloon removal (5 times). Figure 1 provides an overview of this.

Figure 1: Assessment flow chart.

Sample size

Sample size was selected as the optimal size for a pilot study balancing the requirements of obtaining data on potential outcomes with the number of individuals receiving a treatment, with those not shown to be effective, based upon Julious [41].

Statistical analysis

The primary outcome will be the patient’s BMI SDS at sixmonths. As this is a pilot study, with an insufficient sample size to power statistical significance, the mean and standard deviations will be reported. Secondary outcomes include, but are not an exhaustive list, further change in BMI after balloon removal; changes in Blood Pressure, Lipid profile, GLP-1 and GIP levels, bone density and fat mass, adipokines, osteokines, bone turnover markers and Quality of Life scores, with means and standard deviations plotted over time. Analysis of the OGTT results will be performed using a generalised least square (GLS) random-effects model. Longitudinal analysis and multilevel modelling of changes in BMI and biomedical markers will be undertaken to account for changes over time in relation to treatment and other co-variates such as age at baseline and sex.

Time Plan

Recruitment began in November 2011, with all balloon insertions and removals completed by February 2014. Follow-up data will be completed by December 2015.

Author’s contributions

Neil Wright, Jerry Wales and Robert Copeland were responsible for identifying the research question and securing the funding for the research. Lindsey Reece and PoojaSachdev contributed to the development of the protocol as members of the research team. All authors were responsible for the drafting of this paper and read and approved the final version.

Acknowledgements

This paper presents independent research as part of the Obesity Theme within the National Institute for Health Research Collaboration for Leadership in Applied Health Research and Care for South Yorkshire (NIHR CLAHRC SY). The views and opinions expressed are those of the authors, and not necessarily those of the NHS, the NIHR or the Department of Health.

CLAHRC SY would also like to acknowledge the participation and resources of our partner organisations. Further details can be found at www.clahrc-sy.nihr. ac.uk. An additional thank you to LizzyDeAngelis for providing the dietetic expertise in this study.

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